Upgrade backend, objects

Eventually we can have nasin parse cli args and figure out what
files to open, instructing the application to open those files.
We will also be able to have nasin connect to dbus using the
application ID and open files in an already running instance of the
application.

README.md

@@ -1,4 +1,13 @@
 # nasin
 
-Nasin provides an easy way to write applications with Tomo. Parts of Tomo that
-aren't the GUI toolkit may be found here.
+[![Go Reference](https://pkg.go.dev/badge/git.tebibyte.media/tomo/nasin.svg)](https://pkg.go.dev/git.tebibyte.media/tomo/nasin)
+
+Nasin provides an easy way to write applications with Tomo. To get started, take
+a look at the [examples](examples) directory and the
+[online documentation](https://pkg.go.dev/git.tebibyte.media/tomo/nasin).
+
+Related repositories:
+- [Tomo API](https://git.tebibyte.media/tomo/tomo): The API that all other parts
+  of the toolkit agree on
+- [Objects](https://git.tebibyte.media/tomo/objects): A standard collection of
+  re-usable objects and other GUI components

application.go

@@ -1,7 +1,12 @@
 package nasin
 
+import "log"
 import "image"
+import "strings"
+import "net/url"
 import "git.tebibyte.media/tomo/tomo"
+import "git.tebibyte.media/tomo/tomo/canvas"
+import "git.tebibyte.media/tomo/nasin/internal/registrar"
 
 // Application represents an application object.
 type Application interface {
@@ -9,7 +14,21 @@ type Application interface {
 	Describe () ApplicationDescription
 
 	// Init performs the initial setup of the application.
-	Init ()
+	Init () error
+}
+
+// ApplicationURLOpener is an application that can open a URL.
+type ApplicationURLOpener interface {
+	Application
+
+	// OpenURL opens a new window with the contents of the given URL. If the
+	// given URL is unsupported, it returns an error (for example, an image
+	// viewer is not expected to open a text file). If the URL scheme is
+	// empty, file:// is assumed.
+	//
+	// Applications should support the file:// scheme at the very least, and
+	// should also support others like http:// and https:// if possible.
+	OpenURL (*url.URL) error
 }
 
 // ApplicationDescription describes the name and type of an application.
@@ -74,17 +93,60 @@ type ApplicationRole string; const (
 	RoleChecklist         ApplicationRole = "Checklist"
 )
 
-// RunApplication is like Run, but runs an application.
-func RunApplication (application Application) error {
-	return tomo.Run(application.Init)
+// Icon returns the icon ID for this role.
+func (role ApplicationRole) Icon () tomo.Icon {
+	if role == "" {
+		return tomo.IconApplication
+	} else {
+		return tomo.Icon("Application" + strings.ReplaceAll(string(role), " ", ""))
+	}
+}
+
+// RunApplication is like tomo.Run, but runs an application. If something fails
+// to initialize, an error is written to the standard logger.
+func RunApplication (application Application) {
+	err := registrar.RegisterBackend()
+	if err != nil { log.Fatal("nasin: could not register backend:", err) }
+	err = tomo.Run(func () {
+		err := registrar.SetTheme()
+		if err != nil { log.Fatal("nasin: could not set theme:", err) }
+		err = application.Init()
+		if err != nil { log.Fatal("nasin: could not run application:", err) }
+	})
+	if err != nil { log.Fatal("nasin: could not run application:", err) }
 }
 
 // NewApplicationWindow creates a window for an application. It will
 // automatically set window information to signal to the OS that the window is
-// owned by the application.
-func NewApplicationWindow (application Application, bounds image.Rectangle) (tomo.MainWindow, error) {
+// owned by the application. The window's icon will be automatically set by
+// looking for an icon with the name of the application's ID. If that is not
+// found, the default icon for the application's ApplicationRole will used.
+func NewApplicationWindow (application Application, bounds image.Rectangle) (tomo.Window, error) {
 	window, err := tomo.NewWindow(bounds)
 	if err != nil { return nil, err }
-	window.SetTitle(application.Describe().String())
+	description := application.Describe()
+	window.SetTitle(description.Name)
+	setApplicationWindowIcon(window, description)
 	return window, nil
 }
+
+func setApplicationWindowIcon (window tomo.Window, description ApplicationDescription) {
+	allSizes := func (icon tomo.Icon) (sizes []canvas.Texture) {
+		small  := icon.Texture(tomo.IconSizeSmall)
+		medium := icon.Texture(tomo.IconSizeMedium)
+		large  := icon.Texture(tomo.IconSizeLarge)
+		if small  != nil { sizes = append(sizes,  small) }
+		if medium != nil { sizes = append(sizes, medium) }
+		if large  != nil { sizes = append(sizes,  large) }
+		return sizes
+	}
+
+	if sizes := allSizes(tomo.Icon(description.ID)); len(sizes) > 0 {
+		window.SetIcon(sizes...)
+		return
+	}
+	if sizes := allSizes(description.Role.Icon()); len(sizes) > 0 {
+		window.SetIcon(sizes...)
+		return
+	}
+}

backend.go

@@ -1,8 +0,0 @@
-package nasin
-
-import "git.tebibyte.media/tomo/x"
-import "git.tebibyte.media/tomo/tomo"
-
-func init () {
-	tomo.Register(1, x.NewBackend)
-}

examples/clock/main.go

@@ -0,0 +1,125 @@
+// Example clock demonstrates the use of goroutines and tomo.Do() to provide
+// live-updating information.
+package main
+
+import "time"
+import "math"
+import "image"
+import "image/color"
+import "git.tebibyte.media/tomo/tomo"
+import "git.tebibyte.media/tomo/nasin"
+import "git.tebibyte.media/tomo/objects"
+import "git.tebibyte.media/tomo/tomo/canvas"
+import "git.tebibyte.media/tomo/objects/layouts"
+
+type Application struct {
+	clockFace *ClockFace
+	timeLabel *objects.Label
+}
+
+func (this *Application) Describe () nasin.ApplicationDescription {
+	return nasin.ApplicationDescription {
+		Name: "Clock",
+		ID:   "xyz.holanet.TomoClockExample",
+	}
+}
+
+func (this *Application) Init () error {
+	window, err := nasin.NewApplicationWindow(this, image.Rect(0, 0, 128, 160))
+	if err != nil { return err }
+
+	this.clockFace = NewClockFace()
+	this.timeLabel = objects.NewLabel("")
+	this.timeLabel.SetAlign(tomo.AlignMiddle, tomo.AlignMiddle)
+	container := objects.NewOuterContainer (
+		layouts.NewGrid([]bool { true }, []bool { true, false }),
+		this.clockFace,
+		this.timeLabel)
+	window.SetRoot(container)
+
+	go func () {
+		for {
+			tomo.Do(this.updateTime)
+			time.Sleep(time.Second)
+		}
+	} ()
+
+	window.OnClose(tomo.Stop)
+	window.SetVisible(true)
+	return nil
+}
+
+func (this *Application) updateTime () {
+	now := time.Now()
+	this.clockFace.SetTime(now)
+	this.timeLabel.SetText(now.Format(time.DateTime))
+}
+
+func main () {
+	nasin.RunApplication(&Application { })
+}
+
+type ClockFace struct {
+	tomo.CanvasBox
+	time time.Time
+}
+
+func NewClockFace () *ClockFace {
+	box := &ClockFace {
+		CanvasBox: tomo.NewCanvasBox(),
+	}
+	box.SetRole(tomo.R("nasin", "ClockFace", ""))
+	box.SetDrawer(box)
+	return box
+}
+
+// TODO move ClockFace to objects
+
+func (this *ClockFace) SetTime (when time.Time) {
+	this.time = when
+	this.Invalidate()
+}
+
+func (this *ClockFace) Draw (destination canvas.Canvas) {
+	pen := destination.Pen()
+	pen.Fill(color.Transparent)
+	pen.Rectangle(destination.Bounds())
+
+	for hour := 0; hour < 12; hour ++ {
+		radialLine (
+			destination,
+			tomo.ColorForeground,
+			0.8, 0.9, float64(hour) / 6 * math.Pi)
+	}
+
+	second := float64(this.time.Second())
+	minute := float64(this.time.Minute()) + second / 60
+	hour   := float64(this.time.Hour())   + minute / 60
+
+	radialLine(destination, tomo.ColorForeground, 0, 0.5, (hour   - 3)  / 6  * math.Pi)
+	radialLine(destination, tomo.ColorForeground, 0, 0.7, (minute - 15) / 30 * math.Pi)
+	radialLine(destination, tomo.ColorAccent,     0, 0.7, (second - 15) / 30 * math.Pi)
+}
+
+func radialLine (
+	destination canvas.Canvas,
+	source color.Color,
+	inner  float64,
+	outer  float64,
+	theta  float64,
+) {
+	pen := destination.Pen()
+	bounds := destination.Bounds()
+	width  := float64(bounds.Dx()) / 2
+	height := float64(bounds.Dy()) / 2
+	min := bounds.Min.Add(image.Pt (
+		int(math.Cos(theta) * inner * width + width),
+		int(math.Sin(theta) * inner * height + height)))
+	max := bounds.Min.Add(image.Pt (
+		int(math.Cos(theta) * outer * width + width),
+		int(math.Sin(theta) * outer * height + height)))
+	
+	pen.Stroke(source)
+	pen.StrokeWeight(1)
+	pen.Path(min, max)
+}

examples/icons/main.go

@@ -0,0 +1,423 @@
+// Example icons demonstrates the use of icons, and buttons with icons.
+package main
+
+import "image"
+import "git.tebibyte.media/tomo/tomo"
+import "git.tebibyte.media/tomo/nasin"
+import "git.tebibyte.media/tomo/objects"
+import "git.tebibyte.media/tomo/tomo/input"
+import "git.tebibyte.media/tomo/objects/layouts"
+import "git.tebibyte.media/tomo/nasin/internal/icons/xdg"
+
+const scrollIcons = true
+
+type Application struct {
+	window tomo.Window
+	size   tomo.IconSize
+	grid   tomo.ContainerBox
+}
+
+func (this *Application) Describe () nasin.ApplicationDescription {
+	return nasin.ApplicationDescription {
+		Name: "Tomo Icon Example",
+		ID:   "xyz.holanet.TomoIconExample",
+	}
+}
+
+func (this *Application) Init () error {
+	window, err := nasin.NewApplicationWindow(this, image.Rect(0, 0, 128, 256))
+	if err != nil { return err }
+	this.window = window
+
+	this.grid = objects.NewSunkenContainer(layouts.FlowVertical)
+	this.resizeIcons(tomo.IconSizeSmall)
+	
+	iconButtons := objects.NewInnerContainer(layouts.NewGrid([]bool { true, true, true}, []bool { false }))
+
+	button := objects.NewButton("small")
+	button.SetIcon(tomo.IconZoomOut)
+	button.OnClick(func () { this.resizeIcons(tomo.IconSizeSmall) })
+	iconButtons.Add(button)
+	
+	button = objects.NewButton("medium")
+	button.SetIcon(tomo.IconZoomOriginal)
+	button.OnClick(func () { this.resizeIcons(tomo.IconSizeMedium) })
+	iconButtons.Add(button)
+	
+	button = objects.NewButton("large")
+	button.SetIcon(tomo.IconZoomIn)
+	button.OnClick(func () { this.resizeIcons(tomo.IconSizeLarge) })
+	iconButtons.Add(button)
+	
+	container := objects.NewOuterContainer (
+		layouts.NewGrid([]bool { true }, []bool { false, true, false }),
+		objects.NewLabel("A smorgasbord of icons:"))
+	if scrollIcons {
+		iconScroller := objects.NewScrollContainer(objects.ScrollVertical)
+		this.grid.SetOverflow(false, true)
+		iconScroller.SetRoot(this.grid)
+		container.Add(iconScroller)
+	} else {
+		container.Add(this.grid)
+	}
+	container.Add(iconButtons)
+	window.SetRoot(container)
+
+	window.OnClose(tomo.Stop)
+	window.SetVisible(true)
+	return nil
+}
+
+func (this *Application) resizeIcons (size tomo.IconSize) {
+	this.size = size
+	this.grid.Clear()
+	icons := []tomo.Icon {
+		tomo.IconUnknown,
+		tomo.IconAddressBookNew,
+		tomo.IconApplicationExit,
+		tomo.IconAppointmentNew,
+		tomo.IconCallStart,
+		tomo.IconCallStop,
+		tomo.IconContactNew,
+		tomo.IconDialogOkay,
+		tomo.IconDialogCancel,
+		tomo.IconEditClear,
+		tomo.IconEditCopy,
+		tomo.IconEditCut,
+		tomo.IconEditDelete,
+		tomo.IconEditFind,
+		tomo.IconEditFindReplace,
+		tomo.IconEditPaste,
+		tomo.IconEditRedo,
+		tomo.IconEditSelectAll,
+		tomo.IconEditUndo,
+		tomo.IconFileNew,
+		tomo.IconDirectoryNew,
+		tomo.IconFileOpen,
+		tomo.IconFileOpenRecent,
+		tomo.IconFilePageSetup,
+		tomo.IconFilePrint,
+		tomo.IconFilePrintPreview,
+		tomo.IconFilePermissions,
+		tomo.IconFileProperties,
+		tomo.IconFileRename,
+		tomo.IconFileRevert,
+		tomo.IconFileSave,
+		tomo.IconFileSaveAs,
+		tomo.IconFileSend,
+		tomo.IconFormatIndentLess,
+		tomo.IconFormatIndentMore,
+		tomo.IconFormatAlignCenter,
+		tomo.IconFormatAlignEven,
+		tomo.IconFormatAlignLeft,
+		tomo.IconFormatAlignRight,
+		tomo.IconFormatTextDirectionLtr,
+		tomo.IconFormatTextDirectionRtl,
+		tomo.IconFormatTextBold,
+		tomo.IconFormatTextItalic,
+		tomo.IconFormatTextUnderline,
+		tomo.IconFormatTextStrikethrough,
+		tomo.IconGoBottom,
+		tomo.IconGoDown,
+		tomo.IconGoFirst,
+		tomo.IconGoHome,
+		tomo.IconGoJump,
+		tomo.IconGoLast,
+		tomo.IconGoNext,
+		tomo.IconGoPrevious,
+		tomo.IconGoTop,
+		tomo.IconGoUp,
+		tomo.IconHelpAbout,
+		tomo.IconHelpContents,
+		tomo.IconHelpFaq,
+		tomo.IconInsertImage,
+		tomo.IconInsertLink,
+		tomo.IconInsertObject,
+		tomo.IconInsertText,
+		tomo.IconListAdd,
+		tomo.IconListRemove,
+		tomo.IconMailForward,
+		tomo.IconMailMarkImportant,
+		tomo.IconMailMarkJunk,
+		tomo.IconMailMarkNotJunk,
+		tomo.IconMailMarkRead,
+		tomo.IconMailMarkUnread,
+		tomo.IconMailMessageNew,
+		tomo.IconMailReplyAll,
+		tomo.IconMailReplySender,
+		tomo.IconMailSend,
+		tomo.IconMailReceive,
+		tomo.IconMediaEject,
+		tomo.IconMediaPlaybackPause,
+		tomo.IconMediaPlaybackStart,
+		tomo.IconMediaPlaybackStop,
+		tomo.IconMediaRecord,
+		tomo.IconMediaSeekBackward,
+		tomo.IconMediaSeekForward,
+		tomo.IconMediaSkipBackward,
+		tomo.IconMediaSkipForward,
+		tomo.IconObjectFlipHorizontal,
+		tomo.IconObjectFlipVertical,
+		tomo.IconObjectRotateLeft,
+		tomo.IconObjectRotateRight,
+		tomo.IconProcessStop,
+		tomo.IconSystemLockScreen,
+		tomo.IconSystemLogOut,
+		tomo.IconSystemRun,
+		tomo.IconSystemSearch,
+		tomo.IconSystemReboot,
+		tomo.IconSystemShutdown,
+		tomo.IconToolsCheckSpelling,
+		tomo.IconValueIncrement,
+		tomo.IconValueDecrement,
+		tomo.IconValueReset,
+		tomo.IconViewFullscreen,
+		tomo.IconViewRefresh,
+		tomo.IconViewRestore,
+		tomo.IconViewSortAscending,
+		tomo.IconViewSortDescending,
+		tomo.IconWindowClose,
+		tomo.IconWindowNew,
+		tomo.IconZoomFitBest,
+		tomo.IconZoomIn,
+		tomo.IconZoomOriginal,
+		tomo.IconZoomOut,
+		tomo.IconApplication,
+		tomo.IconApplicationWebBrowser,
+		tomo.IconApplicationMesssanger,
+		tomo.IconApplicationPhone,
+		tomo.IconApplicationMail,
+		tomo.IconApplicationTerminalEmulator,
+		tomo.IconApplicationFileBrowser,
+		tomo.IconApplicationTextEditor,
+		tomo.IconApplicationDocumentViewer,
+		tomo.IconApplicationWordProcessor,
+		tomo.IconApplicationSpreadsheet,
+		tomo.IconApplicationSlideshow,
+		tomo.IconApplicationCalculator,
+		tomo.IconApplicationPreferences,
+		tomo.IconApplicationProcessManager,
+		tomo.IconApplicationSystemInformation,
+		tomo.IconApplicationManual,
+		tomo.IconApplicationCamera,
+		tomo.IconApplicationImageViewer,
+		tomo.IconApplicationMediaPlayer,
+		tomo.IconApplicationImageEditor,
+		tomo.IconApplicationAudioEditor,
+		tomo.IconApplicationVideoEditor,
+		tomo.IconApplicationClock,
+		tomo.IconApplicationCalendar,
+		tomo.IconApplicationChecklist,
+		tomo.IconApplications,
+		tomo.IconApplicationsAccessories,
+		tomo.IconApplicationsDevelopment,
+		tomo.IconApplicationsEngineering,
+		tomo.IconApplicationsGames,
+		tomo.IconApplicationsGraphics,
+		tomo.IconApplicationsInternet,
+		tomo.IconApplicationsMultimedia,
+		tomo.IconApplicationsOffice,
+		tomo.IconApplicationsScience,
+		tomo.IconApplicationsSystem,
+		tomo.IconApplicationsUtilities,
+		tomo.IconPreferences,
+		tomo.IconPreferencesDesktop,
+		tomo.IconPreferencesPeripherals,
+		tomo.IconPreferencesPersonal,
+		tomo.IconPreferencesSystem,
+		tomo.IconPreferencesNetwork,
+		tomo.IconDevice,
+		tomo.IconDeviceCamera,
+		tomo.IconDeviceWebCamera,
+		tomo.IconDeviceComputer,
+		tomo.IconDevicePda,
+		tomo.IconDevicePhone,
+		tomo.IconDevicePrinter,
+		tomo.IconDeviceScanner,
+		tomo.IconDeviceMultimediaPlayer,
+		tomo.IconDeviceVideoDisplay,
+		tomo.IconDeviceAudioInput,
+		tomo.IconDeviceAudioOutput,
+		tomo.IconHardware,
+		tomo.IconHardwareCPU,
+		tomo.IconHardwareGPU,
+		tomo.IconHardwareRAM,
+		tomo.IconHardwareSoundCard,
+		tomo.IconHardwareNetworkAdapter,
+		tomo.IconPowerBattery,
+		tomo.IconStorageHardDisk,
+		tomo.IconStorageFloppyDisk,
+		tomo.IconStorageSolidState,
+		tomo.IconStorageOptical,
+		tomo.IconStorageFlashStick,
+		tomo.IconStorageFlashCard,
+		tomo.IconStorageMagneticTape,
+		tomo.IconInputGaming,
+		tomo.IconInputKeyboard,
+		tomo.IconInputMouse,
+		tomo.IconInputTablet,
+		tomo.IconNetworkWired,
+		tomo.IconNetworkWireless,
+		tomo.IconNetworkCellular,
+		tomo.IconNetworkLocal,
+		tomo.IconNetworkInternet,
+		tomo.IconNetworkVPN,
+		tomo.IconNetworkServer,
+		tomo.IconNetworkWorkgroup,
+		tomo.IconEmblemDefault,
+		tomo.IconEmblemEncrypted,
+		tomo.IconEmblemFavorite,
+		tomo.IconEmblemImportant,
+		tomo.IconEmblemReadOnly,
+		tomo.IconEmblemShared,
+		tomo.IconEmblemSymbolicLink,
+		tomo.IconEmblemSynchronized,
+		tomo.IconEmblemSystem,
+		tomo.IconEmblemUnreadable,
+		tomo.IconPlaceDirectory,
+		tomo.IconPlaceRemote,
+		tomo.IconPlaceHome,
+		tomo.IconPlaceDownloads,
+		tomo.IconPlaceDesktop,
+		tomo.IconPlacePhotos,
+		tomo.IconPlaceBooks,
+		tomo.IconPlaceBookmarks,
+		tomo.IconPlaceTrash,
+		tomo.IconPlaceDocuments,
+		tomo.IconPlaceRepositories,
+		tomo.IconPlaceMusic,
+		tomo.IconPlaceArchives,
+		tomo.IconPlaceFonts,
+		tomo.IconPlaceBinaries,
+		tomo.IconPlaceVideos,
+		tomo.IconPlace3DObjects,
+		tomo.IconPlaceHistory,
+		tomo.IconPlacePreferences,
+		tomo.IconCheckboxChecked,
+		tomo.IconCheckboxUnchecked,
+		tomo.IconAppointmentMissed,
+		tomo.IconAppointmentSoon,
+		tomo.IconDialogError,
+		tomo.IconDialogInformation,
+		tomo.IconDialogPassword,
+		tomo.IconDialogQuestion,
+		tomo.IconDialogWarning,
+		tomo.IconDirectoryDragAccept,
+		tomo.IconDirectoryFull,
+		tomo.IconDirectoryOpen,
+		tomo.IconDirectoryVisiting,
+		tomo.IconTrashFull,
+		tomo.IconResourceLoading,
+		tomo.IconResourceMissing,
+		tomo.IconMailAttachment,
+		tomo.IconMailUnread,
+		tomo.IconMailReplied,
+		tomo.IconMailSigned,
+		tomo.IconMailSignedVerified,
+		tomo.IconCellularSignal0,
+		tomo.IconCellularSignal1,
+		tomo.IconCellularSignal2,
+		tomo.IconCellularSignal3,
+		tomo.IconWirelessSignal0,
+		tomo.IconWirelessSignal1,
+		tomo.IconWirelessSignal2,
+		tomo.IconWirelessSignal3,
+		tomo.IconNetworkError,
+		tomo.IconNetworkIdle,
+		tomo.IconNetworkOffline,
+		tomo.IconNetworkReceive,
+		tomo.IconNetworkTransmit,
+		tomo.IconNetworkTransmitReceive,
+		tomo.IconPrintError,
+		tomo.IconPrintPrinting,
+		tomo.IconSecurityHigh,
+		tomo.IconSecurityMedium,
+		tomo.IconSecurityLow,
+		tomo.IconSoftwareUpdateAvailable,
+		tomo.IconSoftwareUpdateUrgent,
+		tomo.IconSoftwareInstalling,
+		tomo.IconSyncError,
+		tomo.IconSyncSynchronizing,
+		tomo.IconTaskDue,
+		tomo.IconTaskPastDue,
+		tomo.IconUserAvailable,
+		tomo.IconUserAway,
+		tomo.IconUserIdle,
+		tomo.IconUserOffline,
+		tomo.IconBattery0,
+		tomo.IconBattery1,
+		tomo.IconBattery2,
+		tomo.IconBattery3,
+		tomo.IconBrightness0,
+		tomo.IconBrightness1,
+		tomo.IconBrightness2,
+		tomo.IconBrightness3,
+		tomo.IconVolume0,
+		tomo.IconVolume1,
+		tomo.IconVolume2,
+		tomo.IconVolume3,
+		tomo.IconPlaylistRepeat,
+		tomo.IconPlaylistShuffle,
+		tomo.IconWeatherClear,
+		tomo.IconWeatherClearNight,
+		tomo.IconWeatherFewClouds,
+		tomo.IconWeatherFewCloudsNight,
+		tomo.IconWeatherFog,
+		tomo.IconWeatherOvercast,
+		tomo.IconWeatherSevereAlert,
+		tomo.IconWeatherShowers,
+		tomo.IconWeatherShowersScattered,
+		tomo.IconWeatherSnow,
+		tomo.IconWeatherStorm,
+	}
+
+	for _, icon := range icons {
+		iconObject := objects.NewIcon(icon, size)
+		this.grid.Add(iconObject)
+		icon := icon
+		iconObject.OnMouseDown(func (button input.Button) {
+			if button != input.ButtonLeft { return }
+			this.iconPopup(icon)
+		})
+	}
+}
+
+func (this *Application) iconPopup (icon tomo.Icon) error {
+	popup, err := this.window.NewModal(image.Rectangle { })
+	if err != nil { return err }
+
+	if icon == "" {
+		icon = "<UNKNOWN>"
+	}
+
+	sizesRow := objects.NewSunkenContainer (
+		layouts.ContractHorizontal,
+		objects.NewIcon(icon, tomo.IconSizeSmall),
+		objects.NewIcon(icon, tomo.IconSizeMedium),
+		objects.NewIcon(icon, tomo.IconSizeLarge))
+	sizesRow.SetAlign(tomo.AlignMiddle, tomo.AlignMiddle)
+
+	okButton := objects.NewButton("OK")
+	okButton.SetFocused(true)
+	okButton.OnClick(popup.Close)
+	okButton.SetIcon(tomo.IconDialogOkay)
+	controlRow := objects.NewInnerContainer (
+		layouts.ContractHorizontal,
+		okButton)
+	controlRow.SetAlign(tomo.AlignEnd, tomo.AlignMiddle)
+	
+	popup.SetRoot(objects.NewOuterContainer (
+		layouts.NewGrid([]bool { true }, []bool { false, false, true, false }),
+		objects.NewLabel("Icon ID: " + string(icon)),
+		objects.NewLabel("XDG Name: " + xdgIcons.XdgIconName(icon)),
+		sizesRow,
+		controlRow,
+	))
+	popup.SetTitle(string(icon) + ": Properties")
+	popup.SetVisible(true)
+	return nil
+}
+
+func main () {
+	nasin.RunApplication(&Application { })
+}

examples/inputs/main.go

@@ -0,0 +1,37 @@
+// Example inputs demonstrates the use of various user input methods.
+package main
+
+import "image"
+import "git.tebibyte.media/tomo/tomo"
+import "git.tebibyte.media/tomo/nasin"
+import "git.tebibyte.media/tomo/objects"
+import "git.tebibyte.media/tomo/objects/layouts"
+
+type Application struct { }
+
+func (this *Application) Describe () nasin.ApplicationDescription {
+	return nasin.ApplicationDescription {
+		Name: "Tomo Input Example",
+		ID:   "xyz.holanet.TomoInputExample",
+	}
+}
+
+func (this *Application) Init () error {
+	window, err := nasin.NewApplicationWindow(this, image.Rect(0, 0, 128, 128))
+	if err != nil { return err }
+
+	window.SetRoot(objects.NewOuterContainer(layouts.ContractVertical,
+		objects.NewTextInput(""),
+		objects.NewHorizontalSlider(0.5),
+		objects.NewLabelCheckbox(false, "checkbox"),
+		objects.NewNumberInput(5),
+	))
+
+	window.OnClose(tomo.Stop)
+	window.SetVisible(true)
+	return nil
+}
+
+func main () {
+	nasin.RunApplication(&Application { })
+}

examples/license/LICENSE

@@ -0,0 +1,674 @@
+                    GNU GENERAL PUBLIC LICENSE
+                       Version 3, 29 June 2007
+
+ Copyright (C) 2007 Free Software Foundation, Inc. <https://fsf.org/>
+ Everyone is permitted to copy and distribute verbatim copies
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+
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+excuse you from the conditions of this License.  If you cannot convey a
+covered work so as to satisfy simultaneously your obligations under this
+License and any other pertinent obligations, then as a consequence you may
+not convey it at all.  For example, if you agree to terms that obligate you
+to collect a royalty for further conveying from those to whom you convey
+the Program, the only way you could satisfy both those terms and this
+License would be to refrain entirely from conveying the Program.
+
+  13. Use with the GNU Affero General Public License.
+
+  Notwithstanding any other provision of this License, you have
+permission to link or combine any covered work with a work licensed
+under version 3 of the GNU Affero General Public License into a single
+combined work, and to convey the resulting work.  The terms of this
+License will continue to apply to the part which is the covered work,
+but the special requirements of the GNU Affero General Public License,
+section 13, concerning interaction through a network will apply to the
+combination as such.
+
+  14. Revised Versions of this License.
+
+  The Free Software Foundation may publish revised and/or new versions of
+the GNU General Public License from time to time.  Such new versions will
+be similar in spirit to the present version, but may differ in detail to
+address new problems or concerns.
+
+  Each version is given a distinguishing version number.  If the
+Program specifies that a certain numbered version of the GNU General
+Public License "or any later version" applies to it, you have the
+option of following the terms and conditions either of that numbered
+version or of any later version published by the Free Software
+Foundation.  If the Program does not specify a version number of the
+GNU General Public License, you may choose any version ever published
+by the Free Software Foundation.
+
+  If the Program specifies that a proxy can decide which future
+versions of the GNU General Public License can be used, that proxy's
+public statement of acceptance of a version permanently authorizes you
+to choose that version for the Program.
+
+  Later license versions may give you additional or different
+permissions.  However, no additional obligations are imposed on any
+author or copyright holder as a result of your choosing to follow a
+later version.
+
+  15. Disclaimer of Warranty.
+
+  THERE IS NO WARRANTY FOR THE PROGRAM, TO THE EXTENT PERMITTED BY
+APPLICABLE LAW.  EXCEPT WHEN OTHERWISE STATED IN WRITING THE COPYRIGHT
+HOLDERS AND/OR OTHER PARTIES PROVIDE THE PROGRAM "AS IS" WITHOUT WARRANTY
+OF ANY KIND, EITHER EXPRESSED OR IMPLIED, INCLUDING, BUT NOT LIMITED TO,
+THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
+PURPOSE.  THE ENTIRE RISK AS TO THE QUALITY AND PERFORMANCE OF THE PROGRAM
+IS WITH YOU.  SHOULD THE PROGRAM PROVE DEFECTIVE, YOU ASSUME THE COST OF
+ALL NECESSARY SERVICING, REPAIR OR CORRECTION.
+
+  16. Limitation of Liability.
+
+  IN NO EVENT UNLESS REQUIRED BY APPLICABLE LAW OR AGREED TO IN WRITING
+WILL ANY COPYRIGHT HOLDER, OR ANY OTHER PARTY WHO MODIFIES AND/OR CONVEYS
+THE PROGRAM AS PERMITTED ABOVE, BE LIABLE TO YOU FOR DAMAGES, INCLUDING ANY
+GENERAL, SPECIAL, INCIDENTAL OR CONSEQUENTIAL DAMAGES ARISING OUT OF THE
+USE OR INABILITY TO USE THE PROGRAM (INCLUDING BUT NOT LIMITED TO LOSS OF
+DATA OR DATA BEING RENDERED INACCURATE OR LOSSES SUSTAINED BY YOU OR THIRD
+PARTIES OR A FAILURE OF THE PROGRAM TO OPERATE WITH ANY OTHER PROGRAMS),
+EVEN IF SUCH HOLDER OR OTHER PARTY HAS BEEN ADVISED OF THE POSSIBILITY OF
+SUCH DAMAGES.
+
+  17. Interpretation of Sections 15 and 16.
+
+  If the disclaimer of warranty and limitation of liability provided
+above cannot be given local legal effect according to their terms,
+reviewing courts shall apply local law that most closely approximates
+an absolute waiver of all civil liability in connection with the
+Program, unless a warranty or assumption of liability accompanies a
+copy of the Program in return for a fee.
+
+                     END OF TERMS AND CONDITIONS
+
+            How to Apply These Terms to Your New Programs
+
+  If you develop a new program, and you want it to be of the greatest
+possible use to the public, the best way to achieve this is to make it
+free software which everyone can redistribute and change under these terms.
+
+  To do so, attach the following notices to the program.  It is safest
+to attach them to the start of each source file to most effectively
+state the exclusion of warranty; and each file should have at least
+the "copyright" line and a pointer to where the full notice is found.
+
+    <one line to give the program's name and a brief idea of what it does.>
+    Copyright (C) <year>  <name of author>
+
+    This program is free software: you can redistribute it and/or modify
+    it under the terms of the GNU General Public License as published by
+    the Free Software Foundation, either version 3 of the License, or
+    (at your option) any later version.
+
+    This program is distributed in the hope that it will be useful,
+    but WITHOUT ANY WARRANTY; without even the implied warranty of
+    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+    GNU General Public License for more details.
+
+    You should have received a copy of the GNU General Public License
+    along with this program.  If not, see <https://www.gnu.org/licenses/>.
+
+Also add information on how to contact you by electronic and paper mail.
+
+  If the program does terminal interaction, make it output a short
+notice like this when it starts in an interactive mode:
+
+    <program>  Copyright (C) <year>  <name of author>
+    This program comes with ABSOLUTELY NO WARRANTY; for details type `show w'.
+    This is free software, and you are welcome to redistribute it
+    under certain conditions; type `show c' for details.
+
+The hypothetical commands `show w' and `show c' should show the appropriate
+parts of the General Public License.  Of course, your program's commands
+might be different; for a GUI interface, you would use an "about box".
+
+  You should also get your employer (if you work as a programmer) or school,
+if any, to sign a "copyright disclaimer" for the program, if necessary.
+For more information on this, and how to apply and follow the GNU GPL, see
+<https://www.gnu.org/licenses/>.
+
+  The GNU General Public License does not permit incorporating your program
+into proprietary programs.  If your program is a subroutine library, you
+may consider it more useful to permit linking proprietary applications with
+the library.  If this is what you want to do, use the GNU Lesser General
+Public License instead of this License.  But first, please read
+<https://www.gnu.org/licenses/why-not-lgpl.html>.

examples/license/main.go

@@ -0,0 +1,62 @@
+// Example license demonstrates the use of a TextView to display licensing 
+// information.
+package main
+
+import "image"
+import _ "embed"
+import "git.tebibyte.media/tomo/tomo"
+import "git.tebibyte.media/tomo/nasin"
+import "git.tebibyte.media/tomo/objects"
+import "git.tebibyte.media/tomo/objects/layouts"
+
+//go:embed LICENSE
+var license []byte
+
+type Application struct { }
+
+func (this *Application) Describe () nasin.ApplicationDescription {
+	return nasin.ApplicationDescription {
+		Name: "Tomo License Example",
+		ID:   "xyz.holanet.TomoLicenseExample",
+	}
+}
+
+func (this *Application) Init () error {
+	window, err := nasin.NewApplicationWindow(this, image.Rect(0, 0, 600, 600))
+	if err != nil { return err }
+
+	checkbox := objects.NewLabelCheckbox(false, "I accept these terms")
+	checkbox.SetFocused(true)
+
+	okButtok := objects.NewButton("OK")
+	okButtok.SetIcon(tomo.IconDialogOkay)
+	okButtok.OnClick(func () {
+		if checkbox.Value() {
+			window.Close()
+		} else {
+			dialog, _ := objects.NewDialogOk (
+				objects.DialogInformation, window,
+				"", "You must read and agree to the license terms", nil)
+			dialog.SetVisible(true)
+		}
+	})
+
+	scroller := objects.NewScrollContainer(objects.ScrollVertical)
+	scroller.SetRoot(objects.NewTextView(string(license)))
+	
+	window.SetRoot(objects.NewOuterContainer (
+		layouts.NewGrid([]bool { true }, []bool { true, false }),
+		scroller,
+		objects.NewInnerContainer (
+			layouts.NewGrid([]bool { true, false }, []bool { true }),
+			checkbox,
+			okButtok)))
+	
+	window.OnClose(tomo.Stop)
+	window.SetVisible(true)
+	return nil
+}
+
+func main () {
+	nasin.RunApplication(&Application { })
+}

go.mod

@@ -3,17 +3,18 @@ module git.tebibyte.media/tomo/nasin
 go 1.20
 
 require (
-	git.tebibyte.media/tomo/tomo v0.30.0
-	git.tebibyte.media/tomo/x v0.6.0
+	git.tebibyte.media/tomo/backend v0.4.1
+	git.tebibyte.media/tomo/objects v0.19.0
+	git.tebibyte.media/tomo/tomo v0.38.0
 	git.tebibyte.media/tomo/xdg v0.1.0
+	golang.org/x/image v0.11.0
 )
 
 require (
-	git.tebibyte.media/tomo/typeset v0.7.0 // indirect
+	git.tebibyte.media/tomo/typeset v0.7.1 // indirect
 	git.tebibyte.media/tomo/xgbkb v1.0.1 // indirect
 	github.com/BurntSushi/freetype-go v0.0.0-20160129220410-b763ddbfe298 // indirect
 	github.com/BurntSushi/graphics-go v0.0.0-20160129215708-b43f31a4a966 // indirect
-	github.com/jezek/xgb v1.1.0 // indirect
-	github.com/jezek/xgbutil v0.0.0-20230603163917-04188eb39cf0 // indirect
-	golang.org/x/image v0.11.0 // indirect
+	github.com/jezek/xgb v1.1.1 // indirect
+	github.com/jezek/xgbutil v0.0.0-20231116234834-47f30c120111 // indirect
 )

go.sum

@@ -1,10 +1,12 @@
 git.tebibyte.media/sashakoshka/xgbkb v1.0.0/go.mod h1:pNcE6TRO93vHd6q42SdwLSTTj25L0Yzggz7yLe0JV6Q=
-git.tebibyte.media/tomo/tomo v0.30.0 h1:JoTklJ7yFVrzre4AwuKBMwzho9GomC9ySw354wDB4f4=
-git.tebibyte.media/tomo/tomo v0.30.0/go.mod h1:C9EzepS9wjkTJjnZaPBh22YvVPyA4hbBAJVU20Rdmps=
-git.tebibyte.media/tomo/typeset v0.7.0 h1:JFpEuGmN6R2XSCvkINYxpH0AyYUqqs+dZYr6OSd91y0=
-git.tebibyte.media/tomo/typeset v0.7.0/go.mod h1:PwDpSdBF3l/EzoIsa2ME7QffVVajnTHZN6l3MHEGe1g=
-git.tebibyte.media/tomo/x v0.6.0 h1:80BRiSwhZCqu6IPKZoQj7t1puKXXJpMB9eWVHQliTHM=
-git.tebibyte.media/tomo/x v0.6.0/go.mod h1:6INfDGlcPyoYVMem64ScD5AZb43PkXDGkfgaNa5GCqQ=
+git.tebibyte.media/tomo/backend v0.4.1 h1:rpkyTAfp/PE56aSqKNxtSN+D/aBSW8wjJ/vTtSgqQhE=
+git.tebibyte.media/tomo/backend v0.4.1/go.mod h1:2G04zmKbzf5fA/xzsjoQRrN55BWZkB+vknFxd3ialZ0=
+git.tebibyte.media/tomo/objects v0.19.0 h1:ibnAoPvkPTiuJGlqQDnoGVZBQiUT/GZo1qqvDDUCK4w=
+git.tebibyte.media/tomo/objects v0.19.0/go.mod h1:GP5BZ6lc2F2D0OxERfr9r46PIk7jFlpq2/BWOpoQDqc=
+git.tebibyte.media/tomo/tomo v0.38.0 h1:K5TP67RxnszudeNfmGZiU5cFTRjFueXiI3NCsgw+05U=
+git.tebibyte.media/tomo/tomo v0.38.0/go.mod h1:C9EzepS9wjkTJjnZaPBh22YvVPyA4hbBAJVU20Rdmps=
+git.tebibyte.media/tomo/typeset v0.7.1 h1:aZrsHwCG5ZB4f5CruRFsxLv5ezJUCFUFsQJJso2sXQ8=
+git.tebibyte.media/tomo/typeset v0.7.1/go.mod h1:PwDpSdBF3l/EzoIsa2ME7QffVVajnTHZN6l3MHEGe1g=
 git.tebibyte.media/tomo/xdg v0.1.0 h1:6G2WYPPiM2IXleCpKKHuJA34BxumwNWuLsUoX3yu5zA=
 git.tebibyte.media/tomo/xdg v0.1.0/go.mod h1:tuaRwRkyYW7mqlxA7P2+V+e10KzcamNoUzcOgaIYKAY=
 git.tebibyte.media/tomo/xgbkb v1.0.1 h1:b3HDUopjdQp1MZrb5Vpil4bOtk3NnNXtfQW27Blw2kE=
@@ -13,10 +15,12 @@ github.com/BurntSushi/freetype-go v0.0.0-20160129220410-b763ddbfe298 h1:1qlsVAQJ
 github.com/BurntSushi/freetype-go v0.0.0-20160129220410-b763ddbfe298/go.mod h1:D+QujdIlUNfa0igpNMk6UIvlb6C252URs4yupRUV4lQ=
 github.com/BurntSushi/graphics-go v0.0.0-20160129215708-b43f31a4a966 h1:lTG4HQym5oPKjL7nGs+csTgiDna685ZXjxijkne828g=
 github.com/BurntSushi/graphics-go v0.0.0-20160129215708-b43f31a4a966/go.mod h1:Mid70uvE93zn9wgF92A/r5ixgnvX8Lh68fxp9KQBaI0=
-github.com/jezek/xgb v1.1.0 h1:wnpxJzP1+rkbGclEkmwpVFQWpuE2PUGNUzP8SbfFobk=
 github.com/jezek/xgb v1.1.0/go.mod h1:nrhwO0FX/enq75I7Y7G8iN1ubpSGZEiA3v9e9GyRFlk=
-github.com/jezek/xgbutil v0.0.0-20230603163917-04188eb39cf0 h1:Pf/0BAbppEOq4azPH6fnvUX2dycAwZdGkdxFn25j44c=
+github.com/jezek/xgb v1.1.1 h1:bE/r8ZZtSv7l9gk6nU0mYx51aXrvnyb44892TwSaqS4=
+github.com/jezek/xgb v1.1.1/go.mod h1:nrhwO0FX/enq75I7Y7G8iN1ubpSGZEiA3v9e9GyRFlk=
 github.com/jezek/xgbutil v0.0.0-20230603163917-04188eb39cf0/go.mod h1:AHecLyFNy6AN9f/+0AH/h1MI7X1+JL5bmCz4XlVZk7Y=
+github.com/jezek/xgbutil v0.0.0-20231116234834-47f30c120111 h1:cX/mTy4LgFtWqr5dCadtdJ4zdh/KtPco5yFLsliaFyU=
+github.com/jezek/xgbutil v0.0.0-20231116234834-47f30c120111/go.mod h1:AHecLyFNy6AN9f/+0AH/h1MI7X1+JL5bmCz4XlVZk7Y=
 github.com/yuin/goldmark v1.4.13/go.mod h1:6yULJ656Px+3vBD8DxQVa3kxgyrAnzto9xy5taEt/CY=
 golang.org/x/crypto v0.0.0-20190308221718-c2843e01d9a2/go.mod h1:djNgcEr1/C05ACkg1iLfiJU5Ep61QUkGW8qpdssI0+w=
 golang.org/x/crypto v0.0.0-20210921155107-089bfa567519/go.mod h1:GvvjBRRGRdwPK5ydBHafDWAxML/pGHZbMvKqRZ5+Abc=

internal/icons/fallback/icon.go

@@ -0,0 +1,455 @@
+package fallbackIcons
+
+import "bytes"
+import "image"
+import _ "embed"
+import _ "image/png"
+import "git.tebibyte.media/tomo/tomo"
+import "git.tebibyte.media/tomo/tomo/data"
+import "git.tebibyte.media/tomo/tomo/canvas"
+
+//go:embed assets/icons-small.png
+var atlasSmallBytes []byte
+//go:embed assets/icons-large.png
+var atlasLargeBytes []byte
+
+func generateSource (data []byte, width int) map[tomo.Icon] canvas.Texture {
+	atlasImage, _, err := image.Decode(bytes.NewReader(data))
+	if err != nil { panic(err) }
+	atlasTexture := tomo.NewTexture(atlasImage)
+
+	source := make(map[tomo.Icon] canvas.Texture)
+	x := 0
+	y := 0
+	
+	row := func () {
+		x = 0
+		y ++
+	}
+	col := func (id tomo.Icon) {
+		source[id] = atlasTexture.SubTexture(image.Rect (
+			x * width,
+			y * width,
+			(x + 1) * width,
+			(y + 1) * width))
+		x++
+	}
+
+	col(tomo.IconUnknown)
+	col(tomo.Icon("File"))
+
+	row()
+	// actions
+	col(tomo.IconAddressBookNew)
+	col(tomo.IconApplicationExit)
+	col(tomo.IconAppointmentNew)
+	col(tomo.IconCallStart)
+	col(tomo.IconCallStop)
+	col(tomo.IconContactNew)
+	// actions: dialog
+	col(tomo.IconDialogOkay)
+	col(tomo.IconDialogCancel)
+	// actions: edit
+	col(tomo.IconEditClear)
+	col(tomo.IconEditCopy)
+	col(tomo.IconEditCut)
+	col(tomo.IconEditDelete)
+	col(tomo.IconEditFind)
+	col(tomo.IconEditFindReplace)
+	col(tomo.IconEditPaste)
+	col(tomo.IconEditRedo)
+	col(tomo.IconEditSelectAll)
+	col(tomo.IconEditUndo)
+	// actions: file
+	col(tomo.IconFileNew)
+	col(tomo.IconDirectoryNew)
+	col(tomo.IconFileOpen)
+	col(tomo.IconFileOpenRecent)
+	col(tomo.IconFilePageSetup)
+	col(tomo.IconFilePrint)
+	col(tomo.IconFilePrintPreview)
+	col(tomo.IconFilePermissions)
+	col(tomo.IconFileProperties)
+	col(tomo.IconFileRename)
+	col(tomo.IconFileRevert)
+	col(tomo.IconFileSave)
+	col(tomo.IconFileSaveAs)
+	col(tomo.IconFileSend)
+
+	row()
+	// actions: format
+	col(tomo.IconFormatIndentLess)
+	col(tomo.IconFormatIndentMore)
+	col(tomo.IconFormatAlignCenter)
+	col(tomo.IconFormatAlignEven)
+	col(tomo.IconFormatAlignLeft)
+	col(tomo.IconFormatAlignRight)
+	col(tomo.IconFormatTextDirectionLtr)
+	col(tomo.IconFormatTextDirectionRtl)
+	col(tomo.IconFormatTextBold)
+	col(tomo.IconFormatTextItalic)
+	col(tomo.IconFormatTextUnderline)
+	col(tomo.IconFormatTextStrikethrough)
+	// actions: go
+	col(tomo.IconGoBottom)
+	col(tomo.IconGoDown)
+	col(tomo.IconGoFirst)
+	col(tomo.IconGoHome)
+	col(tomo.IconGoJump)
+	col(tomo.IconGoLast)
+	col(tomo.IconGoNext)
+	col(tomo.IconGoPrevious)
+	col(tomo.IconGoTop)
+	col(tomo.IconGoUp)
+	// actions: help
+	col(tomo.IconHelpAbout)
+	col(tomo.IconHelpContents)
+	col(tomo.IconHelpFaq)
+	// actions: insert
+	col(tomo.IconInsertImage)
+	col(tomo.IconInsertLink)
+	col(tomo.IconInsertObject)
+	col(tomo.IconInsertText)
+	// actions: list
+	col(tomo.IconListAdd)
+	col(tomo.IconListRemove)
+
+	row()
+	// actions: mail
+	col(tomo.IconMailForward)
+	col(tomo.IconMailMarkImportant)
+	col(tomo.IconMailMarkJunk)
+	col(tomo.IconMailMarkNotJunk)
+	col(tomo.IconMailMarkRead)
+	col(tomo.IconMailMarkUnread)
+	col(tomo.IconMailMessageNew)
+	col(tomo.IconMailReplyAll)
+	col(tomo.IconMailReplySender)
+	col(tomo.IconMailSend)
+	col(tomo.IconMailReceive)
+	// actions: media
+	col(tomo.IconMediaEject)
+	col(tomo.IconMediaPlaybackPause)
+	col(tomo.IconMediaPlaybackStart)
+	col(tomo.IconMediaPlaybackStop)
+	col(tomo.IconMediaRecord)
+	col(tomo.IconMediaSeekBackward)
+	col(tomo.IconMediaSeekForward)
+	col(tomo.IconMediaSkipBackward)
+	col(tomo.IconMediaSkipForward)
+	// actions: object
+	col(tomo.IconObjectFlipHorizontal)
+	col(tomo.IconObjectFlipVertical)
+	col(tomo.IconObjectRotateLeft)
+	col(tomo.IconObjectRotateRight)
+	// actions: process
+	col(tomo.IconProcessStop)
+	// actions: system
+	col(tomo.IconSystemLockScreen)
+	col(tomo.IconSystemLogOut)
+	col(tomo.IconSystemRun)
+	col(tomo.IconSystemSearch)
+	col(tomo.IconSystemReboot)
+	col(tomo.IconSystemShutdown)
+
+	row()
+	// actions: tools
+	col(tomo.IconToolsCheckSpelling)
+	// actions: value
+	col(tomo.IconValueIncrement)
+	col(tomo.IconValueDecrement)
+	col(tomo.IconValueReset)
+	// actions: view
+	col(tomo.IconViewFullscreen)
+	col(tomo.IconViewRefresh)
+	col(tomo.IconViewRestore)
+	col(tomo.IconViewSortAscending)
+	col(tomo.IconViewSortDescending)
+	// actions: window
+	col(tomo.IconWindowClose)
+	col(tomo.IconWindowNew)
+	// actions: zoom
+	col(tomo.IconZoomFitBest)
+	col(tomo.IconZoomIn)
+	col(tomo.IconZoomOriginal)
+	col(tomo.IconZoomOut)
+
+	row()
+	// applications
+	// Keep these in sync with nasin.ApplicationRole!
+	col(tomo.IconApplication)
+	col(tomo.IconApplicationWebBrowser)
+	col(tomo.IconApplicationMesssanger)
+	col(tomo.IconApplicationPhone)
+	col(tomo.IconApplicationMail)
+	col(tomo.IconApplicationTerminalEmulator)
+	col(tomo.IconApplicationFileBrowser)
+	col(tomo.IconApplicationTextEditor)
+	col(tomo.IconApplicationDocumentViewer)
+	col(tomo.IconApplicationWordProcessor)
+	col(tomo.IconApplicationSpreadsheet)
+	col(tomo.IconApplicationSlideshow)
+	col(tomo.IconApplicationCalculator)
+	col(tomo.IconApplicationPreferences)
+	col(tomo.IconApplicationProcessManager)
+	col(tomo.IconApplicationSystemInformation)
+	col(tomo.IconApplicationManual)
+	col(tomo.IconApplicationCamera)
+	col(tomo.IconApplicationImageViewer)
+	col(tomo.IconApplicationMediaPlayer)
+	col(tomo.IconApplicationImageEditor)
+	col(tomo.IconApplicationAudioEditor)
+	col(tomo.IconApplicationVideoEditor)
+	col(tomo.IconApplicationClock)
+	col(tomo.IconApplicationCalendar)
+	col(tomo.IconApplicationChecklist)
+
+	row()
+	// categories: applications
+	col(tomo.IconApplications)
+	col(tomo.IconApplicationsAccessories)
+	col(tomo.IconApplicationsDevelopment)
+	col(tomo.IconApplicationsEngineering)
+	col(tomo.IconApplicationsGames)
+	col(tomo.IconApplicationsGraphics)
+	col(tomo.IconApplicationsInternet)
+	col(tomo.IconApplicationsMultimedia)
+	col(tomo.IconApplicationsOffice)
+	col(tomo.IconApplicationsScience)
+	col(tomo.IconApplicationsSystem)
+	col(tomo.IconApplicationsUtilities)
+	// categories: preferences
+	col(tomo.IconPreferences)
+	col(tomo.IconPreferencesDesktop)
+	col(tomo.IconPreferencesPeripherals)
+	col(tomo.IconPreferencesPersonal)
+	col(tomo.IconPreferencesSystem)
+	col(tomo.IconPreferencesNetwork)
+
+	row()
+	// devices
+	col(tomo.IconDevice)
+	col(tomo.IconDeviceCamera)
+	col(tomo.IconDeviceWebCamera)
+	col(tomo.IconDeviceComputer)
+	col(tomo.IconDevicePda)
+	col(tomo.IconDevicePhone)
+	col(tomo.IconDevicePrinter)
+	col(tomo.IconDeviceScanner)
+	col(tomo.IconDeviceMultimediaPlayer)
+	col(tomo.IconDeviceVideoDisplay)
+	col(tomo.IconDeviceAudioInput)
+	col(tomo.IconDeviceAudioOutput)
+	// devices: hardware
+	col(tomo.IconHardware)
+	col(tomo.IconHardwareCPU)
+	col(tomo.IconHardwareGPU)
+	col(tomo.IconHardwareRAM)
+	col(tomo.IconHardwareSoundCard)
+	col(tomo.IconHardwareNetworkAdapter)
+	// devices: power
+	col(tomo.IconPowerBattery)
+	// devices: storage
+	col(tomo.IconStorageHardDisk)
+	col(tomo.IconStorageFloppyDisk)
+	col(tomo.IconStorageSolidState)
+	col(tomo.IconStorageOptical)
+	col(tomo.IconStorageFlashStick)
+	col(tomo.IconStorageFlashCard)
+	col(tomo.IconStorageMagneticTape)
+	// devices: input
+	col(tomo.IconInputGaming)
+	col(tomo.IconInputKeyboard)
+	col(tomo.IconInputMouse)
+	col(tomo.IconInputTablet)
+
+	row()
+	// devices: network
+	col(tomo.IconNetworkWired)
+	col(tomo.IconNetworkWireless)
+	col(tomo.IconNetworkCellular)
+	col(tomo.IconNetworkLocal)
+	col(tomo.IconNetworkInternet)
+	col(tomo.IconNetworkVPN)
+	col(tomo.IconNetworkServer)
+	col(tomo.IconNetworkWorkgroup)
+
+	row()
+	// emblems
+	col(tomo.IconEmblemDefault)
+	col(tomo.IconEmblemEncrypted)
+	col(tomo.IconEmblemFavorite)
+	col(tomo.IconEmblemImportant)
+	col(tomo.IconEmblemReadOnly)
+	col(tomo.IconEmblemShared)
+	col(tomo.IconEmblemSymbolicLink)
+	col(tomo.IconEmblemSynchronized)
+	col(tomo.IconEmblemSystem)
+	col(tomo.IconEmblemUnreadable)
+
+	row()
+	// places
+	col(tomo.IconPlaceDirectory)
+	col(tomo.IconPlaceRemote)
+	col(tomo.IconPlaceHome)
+	col(tomo.IconPlaceDownloads)
+	col(tomo.IconPlaceDesktop)
+	col(tomo.IconPlacePhotos)
+	col(tomo.IconPlaceBooks)
+	col(tomo.IconPlaceBookmarks)
+	col(tomo.IconPlaceTrash)
+	col(tomo.IconPlaceDocuments)
+	col(tomo.IconPlaceRepositories)
+	col(tomo.IconPlaceMusic)
+	col(tomo.IconPlaceArchives)
+	col(tomo.IconPlaceFonts)
+	col(tomo.IconPlaceBinaries)
+	col(tomo.IconPlaceVideos)
+	col(tomo.IconPlace3DObjects)
+	col(tomo.IconPlaceHistory)
+	col(tomo.IconPlacePreferences)
+
+	row()
+	// status: checkbox
+	col(tomo.IconCheckboxChecked)
+	col(tomo.IconCheckboxUnchecked)
+	// status: appointments
+	col(tomo.IconAppointmentMissed)
+	col(tomo.IconAppointmentSoon)
+	// status: dialogs
+	col(tomo.IconDialogError)
+	col(tomo.IconDialogInformation)
+	col(tomo.IconDialogPassword)
+	col(tomo.IconDialogQuestion)
+	col(tomo.IconDialogWarning)
+	// status: directories
+	col(tomo.IconDirectoryDragAccept)
+	col(tomo.IconDirectoryFull)
+	col(tomo.IconDirectoryOpen)
+	col(tomo.IconDirectoryVisiting)
+	// status: trash
+	col(tomo.IconTrashFull)
+	// status: resource
+	col(tomo.IconResourceLoading)
+	col(tomo.IconResourceMissing)
+	// status: mail
+	col(tomo.IconMailAttachment)
+	col(tomo.IconMailUnread)
+	col(tomo.IconMailReplied)
+	col(tomo.IconMailSigned)
+	col(tomo.IconMailSignedVerified)
+
+	row()
+	// status: network
+	col(tomo.IconCellularSignal0)
+	col(tomo.IconCellularSignal1)
+	col(tomo.IconCellularSignal2)
+	col(tomo.IconCellularSignal3)
+	col(tomo.IconWirelessSignal0)
+	col(tomo.IconWirelessSignal1)
+	col(tomo.IconWirelessSignal2)
+	col(tomo.IconWirelessSignal3)
+	col(tomo.IconNetworkError)
+	col(tomo.IconNetworkIdle)
+	col(tomo.IconNetworkOffline)
+	col(tomo.IconNetworkReceive)
+	col(tomo.IconNetworkTransmit)
+	col(tomo.IconNetworkTransmitReceive)
+	// status: print
+	col(tomo.IconPrintError)
+	col(tomo.IconPrintPrinting)
+	// status: security
+	col(tomo.IconSecurityHigh)
+	col(tomo.IconSecurityMedium)
+	col(tomo.IconSecurityLow)
+	// status: software
+	col(tomo.IconSoftwareUpdateAvailable)
+	col(tomo.IconSoftwareUpdateUrgent)
+	col(tomo.IconSoftwareInstalling)
+	// status: sync
+	col(tomo.IconSyncError)
+	col(tomo.IconSyncSynchronizing)
+	// status: tasks
+	col(tomo.IconTaskDue)
+	col(tomo.IconTaskPastDue)
+	// status: users
+	col(tomo.IconUserAvailable)
+	col(tomo.IconUserAway)
+	col(tomo.IconUserIdle)
+	col(tomo.IconUserOffline)
+
+	row()
+	// status: power
+	col(tomo.IconBattery0)
+	col(tomo.IconBattery1)
+	col(tomo.IconBattery2)
+	col(tomo.IconBattery3)
+	col(tomo.IconBrightness0)
+	col(tomo.IconBrightness1)
+	col(tomo.IconBrightness2)
+	col(tomo.IconBrightness3)
+	// status: media
+	col(tomo.IconVolume0)
+	col(tomo.IconVolume1)
+	col(tomo.IconVolume2)
+	col(tomo.IconVolume3)
+	col(tomo.IconPlaylistRepeat)
+	col(tomo.IconPlaylistShuffle)
+	// status: weather
+	col(tomo.IconWeatherClear)
+	col(tomo.IconWeatherClearNight)
+	col(tomo.IconWeatherFewClouds)
+	col(tomo.IconWeatherFewCloudsNight)
+	col(tomo.IconWeatherFog)
+	col(tomo.IconWeatherOvercast)
+	col(tomo.IconWeatherSevereAlert)
+	col(tomo.IconWeatherShowers)
+	col(tomo.IconWeatherShowersScattered)
+	col(tomo.IconWeatherSnow)
+	col(tomo.IconWeatherStorm)
+	
+	return source
+}
+
+type iconTheme struct {
+	texturesSmall map[tomo.Icon] canvas.Texture
+	texturesLarge map[tomo.Icon] canvas.Texture
+}
+
+// New creates a new fallback icon theme.
+func New () tomo.Icons {
+	return new(iconTheme)
+}
+
+func (this *iconTheme) ensure () {
+	if this.texturesSmall != nil { return }
+	this.texturesSmall = generateSource(atlasSmallBytes, 16)
+	this.texturesLarge = generateSource(atlasLargeBytes, 32)
+}
+
+func (this *iconTheme) selectSource (size tomo.IconSize) map[tomo.Icon] canvas.Texture {
+	if size == tomo.IconSizeSmall {
+		return this.texturesSmall
+	} else {
+		return this.texturesLarge
+	}
+}
+
+func (this *iconTheme) Icon (icon tomo.Icon, size tomo.IconSize) canvas.Texture {
+	this.ensure()
+	source := this.selectSource(size)
+	if texture, ok := source[icon]; ok {
+		return texture
+	}
+	return nil
+}
+
+func (this *iconTheme) MimeIcon (mime data.Mime, size tomo.IconSize) canvas.Texture {
+	this.ensure()
+	source := this.selectSource(size)
+	if mime == data.M("inode", "directory") {
+		return source[tomo.IconPlaceDirectory]
+	} else {
+		return source[tomo.Icon("File")]
+	}
+}

internal/icons/xdg/icon.go

@@ -0,0 +1,182 @@
+package xdgIcons
+
+import "os"
+import "fmt"
+import "log"
+import "image"
+import "regexp"
+import "strings"
+import _ "image/png"
+import "git.tebibyte.media/tomo/tomo"
+import xdgIconTheme "git.tebibyte.media/tomo/xdg/icon-theme"
+import "git.tebibyte.media/tomo/tomo/data"
+import "git.tebibyte.media/tomo/tomo/canvas"
+
+type iconTheme struct {
+	xdg xdgIconTheme.Theme
+	fallback       tomo.Icons
+	texturesSmall  map[tomo.Icon] canvas.Texture
+	texturesMedium map[tomo.Icon] canvas.Texture
+	texturesLarge  map[tomo.Icon] canvas.Texture
+}
+
+func FindThemeWarn (name string, fallback tomo.Icons, path ...string) (tomo.Icons, error) {
+	this := &iconTheme {
+		fallback:       fallback,
+		texturesLarge:  make(map[tomo.Icon] canvas.Texture),
+		texturesMedium: make(map[tomo.Icon] canvas.Texture),
+		texturesSmall:  make(map[tomo.Icon] canvas.Texture),
+	}
+	
+	xdg, err := xdgIconTheme.FindThemeWarn(name, path...)
+	if err != nil { return nil, err }
+	this.xdg = xdg
+	
+	return this, nil
+}
+
+func (this *iconTheme) selectSource (size tomo.IconSize) map[tomo.Icon] canvas.Texture {
+	switch size {
+	case tomo.IconSizeMedium: return this.texturesMedium
+	case tomo.IconSizeLarge:  return this.texturesLarge
+	default:                  return this.texturesSmall
+	}
+}
+
+func (this *iconTheme) xdgIcon (name string, size tomo.IconSize) (canvas.Texture, bool) {
+	// TODO use scaling factor instead of 1
+	// find icon file
+	icon, err := this.xdg.FindIcon(name, iconSizePixels(size), 1, xdgIconTheme.PNG)
+	if err != nil { return nil, false }
+
+	// open icon file
+	iconFile, err := os.Open(icon.Path)
+	if err != nil {
+		// this failing indicates a broken icon theme
+		log.Printf("nasin: icon file '%s' is inaccessible: %v\n", icon.Path, err)
+		return nil, false
+	}
+
+	iconImage, _, err := image.Decode(iconFile)
+	if err != nil {
+		// this failing indicates a broken icon theme
+		log.Printf("nasin: icon file '%s' is broken: %v\n", icon.Path, err)
+		return nil, false
+	}
+
+	return tomo.NewTexture(iconImage), true
+}
+
+func (this *iconTheme) Icon (icon tomo.Icon, size tomo.IconSize) canvas.Texture {
+	source := this.selectSource(size)
+	texture, ok := source[icon]
+	if !ok {
+		texture = this.icon(icon, size)
+		source[icon] = texture
+	}
+
+	if texture == nil {
+		return this.fallback.Icon(icon, size)
+	} else {
+		return texture
+	}
+}
+
+func (this *iconTheme) MimeIcon (mime data.Mime, size tomo.IconSize) canvas.Texture {
+	icon := tomo.Icon(mime.String())
+	source := this.selectSource(size)
+	texture, ok := source[icon]
+	if !ok {
+		texture = this.mimeIcon(mime, size)
+		source[icon] = texture
+	}
+
+	if texture == nil {
+		return this.fallback.MimeIcon(mime, size)
+	} else {
+		return texture
+	}
+}
+
+func (this *iconTheme) icon (icon tomo.Icon, size tomo.IconSize) canvas.Texture {
+	if texture, ok := this.xdgIcon(XdgIconName(icon), size); ok {
+		return texture
+	}
+	if texture, ok := this.xdgIcon(XdgIconName(generalizeIcon(icon)), size); ok {
+		return texture
+	}
+	return nil
+}
+
+func (this *iconTheme) mimeIcon (mime data.Mime, size tomo.IconSize) canvas.Texture {
+	if texture, ok := this.xdgIcon(xdgFormatMime(mime), size); ok {
+		return texture
+	}
+	if texture, ok := this.xdgIcon(xdgFormatMime(generalizeMimeType(mime)), size); ok {
+		return texture
+	}
+	if texture, ok := this.xdgIcon(xdgFormatMime(data.M("text", "x-generic")), size); ok {
+		return texture
+	}
+	return nil
+}
+
+var kebabMatchFirstCap = regexp.MustCompile("(.)([A-Z][a-z]+)")
+var kebabMatchAllCaps  = regexp.MustCompile("([a-z0-9])([A-Z])")
+
+// XdgIconName returns the best XDG name for the given icon.
+func XdgIconName (icon tomo.Icon) string {
+	if name, ok := xdgIconNames[icon]; ok {
+		return name
+	}
+
+	name := kebabMatchFirstCap.ReplaceAllString(string(icon), "${1}-${2}")
+	name  = kebabMatchAllCaps.ReplaceAllString(string(name), "${1}-${2}")
+	return strings.ToLower(name)
+}
+
+func generalizeIcon (icon tomo.Icon) tomo.Icon {
+	name := string(icon)
+	switch {
+	case strings.HasPrefix(name, "Application"): return tomo.IconApplication
+	case strings.HasPrefix(name, "Preferences"): return tomo.IconPreferences
+	case strings.HasPrefix(name, "Device"):      return tomo.IconDevice
+	case strings.HasPrefix(name, "Hardware"):    return tomo.IconHardware
+	case strings.HasPrefix(name, "Storage"):     return tomo.IconStorageHardDisk
+	case strings.HasPrefix(name, "Input"):       return tomo.IconInputMouse
+	case strings.HasPrefix(name, "Network"):     return tomo.IconNetworkWired
+	case strings.HasPrefix(name, "Place"):       return tomo.IconPlaceDirectory
+	case strings.HasPrefix(name, "Directory"):   return tomo.IconPlaceDirectory
+	case strings.HasPrefix(name, "Trash"):       return tomo.IconPlaceTrash
+	case strings.HasPrefix(name, "Help"):        return tomo.IconHelpContents
+	}
+
+	switch icon {
+	case tomo.IconCellularSignal0: return tomo.IconWirelessSignal0
+	case tomo.IconCellularSignal1: return tomo.IconWirelessSignal1
+	case tomo.IconCellularSignal2: return tomo.IconWirelessSignal2
+	case tomo.IconCellularSignal3: return tomo.IconWirelessSignal3
+	}
+
+	return icon
+}
+
+func xdgFormatMime (mime data.Mime) string {
+	return fmt.Sprintf("%s-%s", mime.Type, mime.Subtype)
+}
+
+func generalizeMimeType (mime data.Mime) data.Mime {
+	// FIXME make this more accurate
+	// https://specifications.freedesktop.org/icon-naming-spec/icon-naming-spec-latest.html
+	mime.Subtype = "x-generic"
+	return mime
+}
+
+func iconSizePixels (size tomo.IconSize) int {
+	// TODO: once Tomo has scaling support, take that into account here
+	switch size {
+	case tomo.IconSizeMedium: return 24
+	case tomo.IconSizeLarge:  return 48
+	default:                  return 16
+	}
+}

internal/icons/xdg/xdgiconname.go

@@ -0,0 +1,136 @@
+package xdgIcons
+
+import "git.tebibyte.media/tomo/tomo"
+
+// icons that can't be directly translated with regex
+var xdgIconNames = map[tomo.Icon] string {
+	tomo.IconUnknown:                      "image-missing",
+	tomo.IconFileNew:                      "document-new",
+	tomo.IconDirectoryNew:                 "folder-new",
+	tomo.IconFileOpen:                     "document-open",
+	tomo.IconFileOpenRecent:               "document-open-recent",
+	tomo.IconFilePageSetup:                "document-page-setup",
+	tomo.IconFilePrint:                    "document-print",
+	tomo.IconFilePrintPreview:             "document-print-preview",
+	tomo.IconFilePermissions:              "document-permissions",        // non-standard
+	tomo.IconFileProperties:               "document-properties",
+	tomo.IconFileRename:                   "document-rename",             // non-standard
+	tomo.IconFileRevert:                   "document-revert",
+	tomo.IconFileSave:                     "document-save",
+	tomo.IconFileSaveAs:                   "document-save-as",
+	tomo.IconFileSend:                     "document-send",
+	tomo.IconFormatAlignCenter:            "format-justify-center",
+	tomo.IconFormatAlignEven:              "format-justify-fill",
+	tomo.IconFormatAlignLeft:              "format-justify-left",
+	tomo.IconFormatAlignRight:             "format-justify-right",
+	tomo.IconMailReceive:                  "mail-send-receive",
+	tomo.IconValueIncrement:               "list-add",
+	tomo.IconValueDecrement:               "list-remove",
+	tomo.IconValueReset:                   "value-reset",                 // non-standard
+	tomo.IconApplication:                  "system-run",
+	tomo.IconApplicationWebBrowser:        "web-browser",
+	tomo.IconApplicationMesssanger:        "internet-messanger",          // non-standard
+	tomo.IconApplicationPhone:             "accessories-phone",           // non-standard
+	tomo.IconApplicationMail:              "internet-mail-client",        // non-standard
+	tomo.IconApplicationTerminalEmulator:  "utilities-terminal",
+	tomo.IconApplicationFileBrowser:       "system-file-manager",
+	tomo.IconApplicationTextEditor:        "accessories-text-editor",
+	tomo.IconApplicationDocumentViewer:    "office-document-viewer",      // non-standard
+	tomo.IconApplicationWordProcessor:     "office-word-processor",       // non-standard
+	tomo.IconApplicationSpreadsheet:       "office-spreadsheet",          // non-standard
+	tomo.IconApplicationSlideshow:         "office-slideshow",            // non-standard
+	tomo.IconApplicationCalculator:        "accessories-calculator",
+	tomo.IconApplicationPreferences:       "preferences-system",
+	tomo.IconApplicationProcessManager:    "utilities-system-monitor",
+	tomo.IconApplicationSystemInformation: "distributor-logo",            // non-standard
+	tomo.IconApplicationManual:            "help-browser",
+	tomo.IconApplicationCamera:            "accessories-camera",          // non-standard
+	tomo.IconApplicationImageViewer:       "graphics-image-viewer",       // non-standard
+	tomo.IconApplicationMediaPlayer:       "audio-video-media-player",    // non-standard
+	tomo.IconApplicationImageEditor:       "graphics-image-editor",       // non-standard
+	tomo.IconApplicationAudioEditor:       "audio-audio-editor",          // non-standard
+	tomo.IconApplicationVideoEditor:       "video-video-editor",          // non-standard
+	tomo.IconApplicationClock:             "accessories-clock",           // non-standard
+	tomo.IconApplicationCalendar:          "accessories-calendar",        // non-standard
+	tomo.IconApplicationChecklist:         "accessories-checklist",       // non-standard
+	tomo.IconApplications:                 "applications-other",
+	tomo.IconPreferences:                  "preferences-other",
+	tomo.IconPreferencesNetwork:           "preferences-system-network",
+	tomo.IconDevice:                       "device",                      // non-standard
+	tomo.IconDeviceCamera:                 "camera-photo",
+	tomo.IconDeviceWebCamera:              "camera-web",
+	tomo.IconDeviceComputer:               "computer",
+	tomo.IconDevicePda:                    "pda",
+	tomo.IconDevicePhone:                  "phone",
+	tomo.IconDevicePrinter:                "printer",
+	tomo.IconDeviceScanner:                "scanner",
+	tomo.IconDeviceMultimediaPlayer:       "multimedia-player",
+	tomo.IconDeviceVideoDisplay:           "video-display",
+	tomo.IconDeviceAudioInput:             "audio-input-microphone",
+	tomo.IconDeviceAudioOutput:            "audio-speakers",
+	tomo.IconHardware:                     "card",                        // non-standard
+	tomo.IconHardwareCPU:                  "cpu",
+	tomo.IconHardwareGPU:                  "video-card",
+	tomo.IconHardwareRAM:                  "ram",
+	tomo.IconHardwareSoundCard:            "audio-card",
+	tomo.IconHardwareNetworkAdapter:       "network-card",
+	tomo.IconPowerBattery:                 "battery",
+	tomo.IconStorageHardDisk:              "drive-harddisk",
+	tomo.IconStorageFloppyDisk:            "media-floppy",
+	tomo.IconStorageSolidState:            "drive-solid",
+	tomo.IconStorageOptical:               "media-optical",
+	tomo.IconStorageFlashStick:            "media-removable",
+	tomo.IconStorageFlashCard:             "media-flash",
+	tomo.IconStorageMagneticTape:          "media-tape",
+	tomo.IconEmblemReadOnly:               "emblem-readonly",
+	tomo.IconPlaceDirectory:               "folder",
+	tomo.IconPlaceRemote:                  "folder-remote",
+	tomo.IconPlaceHome:                    "user-home",
+	tomo.IconPlaceDownloads:               "folder-downloads",            // common
+	tomo.IconPlaceDesktop:                 "user-desktop",
+	tomo.IconPlacePhotos:                  "folder-pictures",             // common
+	tomo.IconPlaceBooks:                   "folder-books",                // non-standard
+	tomo.IconPlaceBookmarks:               "user-bookmarks",
+	tomo.IconPlaceTrash:                   "user-trash",
+	tomo.IconPlaceDocuments:               "folder-documents",            // common
+	tomo.IconPlaceRepositories:            "folder-repositories",         // non-standard
+	tomo.IconPlaceMusic:                   "folder-music",                // common
+	tomo.IconPlaceArchives:                "folder-archives",             // non-standard
+	tomo.IconPlaceFonts:                   "folder-fonts",                // non-standard
+	tomo.IconPlaceBinaries:                "folder-executables",          // non-standard
+	tomo.IconPlaceVideos:                  "folder-videos",               // common
+	tomo.IconPlace3DObjects:               "folder-3d-objects",           // non-standard
+	tomo.IconPlaceHistory:                 "folder-history",              // non-standard
+	tomo.IconPlacePreferences:             "preferences-other",
+	tomo.IconDirectoryDragAccept:          "folder-drag-accept",
+	tomo.IconDirectoryFull:                "folder-full",
+	tomo.IconDirectoryOpen:                "folder-open",
+	tomo.IconDirectoryVisiting:            "folder-visiting",
+	tomo.IconTrashFull:                    "user-trash-full",
+	tomo.IconResourceLoading:              "image-loading",
+	tomo.IconResourceMissing:              "image-missing",
+	tomo.IconCellularSignal0:              "nm-signal-00",                // common
+	tomo.IconCellularSignal1:              "nm-signal-25",                // common
+	tomo.IconCellularSignal2:              "nm-signal-75",                // common
+	tomo.IconCellularSignal3:              "nm-signal-100",               // common
+	tomo.IconWirelessSignal0:              "wifi-signal-00",              // common
+	tomo.IconWirelessSignal1:              "wifi-signal-25",              // common
+	tomo.IconWirelessSignal2:              "wifi-signal-75",              // common
+	tomo.IconWirelessSignal3:              "wifi-signal-100",             // common
+	tomo.IconPrintError:                   "printer-error",
+	tomo.IconPrintPrinting:                "printer-printing",
+	tomo.IconBattery0:                     "battery-caution",
+	tomo.IconBattery1:                     "battery-low",
+	tomo.IconBattery2:                     "battery-good",                // common
+	tomo.IconBattery3:                     "battery-full",                // common
+	tomo.IconBrightness0:                  "brightness-dim",              // non-standard
+	tomo.IconBrightness1:                  "brightness-medium",           // non-standard
+	tomo.IconBrightness2:                  "brightness-bright",           // non-standard
+	tomo.IconBrightness3:                  "brightness-full",             // non-standard
+	tomo.IconVolume0:                      "audio-volume-muted",
+	tomo.IconVolume1:                      "audio-volume-low",
+	tomo.IconVolume2:                      "audio-volume-medium",
+	tomo.IconVolume3:                      "audio-volume-high",
+	tomo.IconPlaylistRepeat:               "media-playlist-repeat",
+	tomo.IconPlaylistShuffle:              "media-playlist-shuffle",
+}

internal/registrar/doc.go

@@ -0,0 +1,2 @@
+// Package registrar provides platform-dependent components at compile time.
+package registrar

internal/registrar/registrar_unix.go

@@ -0,0 +1,43 @@
+//go:build unix && (!darwin)
+package registrar
+
+import "os"
+import "log"
+import "git.tebibyte.media/tomo/tomo"
+import "git.tebibyte.media/tomo/backend/x"
+import "git.tebibyte.media/tomo/nasin/internal/style"
+import "git.tebibyte.media/tomo/nasin/internal/icons/xdg"
+import "git.tebibyte.media/tomo/nasin/internal/icons/fallback"
+import "git.tebibyte.media/tomo/nasin/internal/style/fallback"
+import "git.tebibyte.media/tomo/nasin/internal/style/aluminum"
+
+func RegisterBackend () error {
+	tomo.Register(1, x.New)
+	return nil
+}
+
+func SetTheme () error {
+	var styl *style.Style
+	// TODO eventually get rid of this when we make a file format for
+	// storing visual styles
+	if os.Getenv("TOMO_USE_ALUMINUM_STYLE") != "" {
+		styl = aluminumStyle.New()
+	} else {
+		styl = fallbackStyle.New()
+	}
+	icons := fallbackIcons.New()
+	
+	iconThemeName := os.Getenv("TOMO_XDG_ICON_THEME")
+	if iconThemeName != "" {
+		xdgIconTheme, err := xdgIcons.FindThemeWarn(iconThemeName, icons)
+		if err == nil {
+			icons = xdgIconTheme
+		} else {
+			log.Printf("nasin: could not load icon theme '%s': %v", iconThemeName, err)
+		}
+	}
+	
+	tomo.SetStyle(styl)
+	tomo.SetIcons(icons)
+	return nil	
+}

internal/style/aluminum/aluminum.go

@@ -0,0 +1,19 @@
+package aluminumStyle
+
+import "image/color"
+import "git.tebibyte.media/tomo/tomo"
+import "git.tebibyte.media/tomo/nasin/internal/style"
+
+// New returns Aluminum, a futuristic, bluish-white style.
+func New () *style.Style {
+	return &style.Style {
+		Colors: map[tomo.Color] color.Color {
+			tomo.ColorBackground: colorBackground,
+			tomo.ColorForeground: colorForeground,
+			tomo.ColorRaised:     colorRaised,
+			tomo.ColorSunken:     colorSunken,
+			tomo.ColorAccent:     colorFocus,
+		},
+		Rules: rules,
+	}
+}

internal/style/aluminum/style.go

@@ -0,0 +1,392 @@
+package aluminumStyle
+
+import "image/color"
+import "git.tebibyte.media/tomo/tomo"
+import "golang.org/x/image/font/basicfont"
+import "git.tebibyte.media/tomo/nasin/internal/style"
+
+func hex (color uint32) (c color.RGBA) {
+	c.A = uint8(color)
+	c.B = uint8(color >>  8)
+	c.G = uint8(color >> 16)
+	c.R = uint8(color >> 24)
+	return
+}
+
+func border (top, right, bottom, left uint32, width ...int) tomo.Border {
+	return tomo.Border {
+		Width: tomo.I(width...),
+		Color: [4]color.Color {
+			hex(top),    hex(right),
+			hex(bottom), hex(left),
+		},
+	}
+}
+
+var colorDot                   = hex(0x7391c080)
+var colorFocus                 = hex(0x5f8bc4FF)
+var colorHighlight             = hex(0x5f8bc4FF)
+var colorBackground            = hex(0xd4d4d4FF)
+var colorForeground            = color.Black
+
+var colorOutline               = color.Black
+var colorGutter                = hex(0xbfc6d1FF)
+var colorGutterHovered         = hex(0xc5cbd6FF)
+var colorRaised                = hex(0xe9eaeaFF)
+var colorRaisedPressed         = hex(0xccd4ddFF)
+var colorRaisedFocused         = hex(0xcfd6ddFF)
+var colorRaisedHovered         = hex(0xf1f3f5FF)
+var colorSunken                = hex(0xe9eaeaFF)
+var colorSunkenFocused         = hex(0xe0e6eeFF)
+var colorSunkenPressed         = hex(0xe0e6eeFF)
+var colorCalendarWeekdayHeader = hex(0xd3cac2FF)
+var colorCalendarWeekend       = hex(0xc2d3c4FF)
+var colorCalendarDay           = hex(0xd6dae2FF)
+
+var outline = tomo.Border {
+	Width: tomo.I(1),
+	Color: [4]color.Color {
+		colorOutline,
+		colorOutline,
+		colorOutline,
+		colorOutline,
+	},
+}
+
+var borderEngraved       = border(0xc3c3c5FF, 0xe3e3e3FF, 0xe9e9e9ff, 0xc2c2c2ff, 1)
+var borderGap            = border(0x697c7cFF, 0x566767FF, 0x566767ff, 0x697c7cff, 1)
+var borderLifted         = border(0xf9fafcFF, 0xc2c8d3FF, 0xa4afc0ff, 0xf5f6f8ff, 1)
+var borderLiftedFocused  = border(0xf0f4f9FF, 0xb1bacaFF, 0x9aa6b7ff, 0xe4e9eeff, 1)
+var borderFocused        = border(0x5f8bc4FF, 0x5f8bc4FF, 0x5f8bc4ff, 0x5f8bc4ff, 1)
+var borderTear           = borderEngraved
+var borderTearFocused    = border(0x7f94b5FF, 0xced7e4FF, 0xced7e4FF, 0x7f94b5FF, 1)
+var borderTearPad        = border(0x00000000, 0x00000000, 0x00000000, 0x00000000, 3)
+var borderTearPadFocused = border(0x7391c080, 0x7391c080, 0x7391c080, 0x7391c080, 3)
+var borderInnerShadow    = border(0xa4afc0FF, 0xa4afc0FF, 0xa4afc0ff, 0xa4afc0ff, 1, 0, 0, 1)
+var borderOuterShadow    = border(0xa4afc0FF, 0xa4afc0FF, 0xa4afc0ff, 0xa4afc0ff, 0, 1, 1, 0)
+
+var rules = []style.Rule {
+	// *.*[*]
+	style.Rule {
+		Default: style.AS (
+			style.AttrFace      { Face:  basicfont.Face7x13    },
+			style.AttrTextColor { Color: tomo.ColorForeground  },
+			style.AttrDotColor  { Color: colorDot              },
+			style.AttrGap       { X: 8, Y: 8                   },
+		),
+	},
+
+	// *.Button[*]
+	style.Rule {
+		Role: tomo.R("", "Button", ""),
+		Default: style.AS (
+			style.AttrBorder {
+				borderEngraved,
+				borderGap,
+				borderLifted,
+			},
+			style.AttrPadding(tomo.I(4, 8)),
+			style.AttrColor { Color: tomo.ColorRaised },
+		),
+		Pressed: style.AS (
+			style.AttrBorder {
+				borderEngraved,
+				borderGap,
+				borderInnerShadow,
+			},
+			style.AttrPadding(tomo.I(5, 8, 4, 9)),
+			style.AttrColor { Color: colorRaisedPressed },
+		),
+		Focused: style.AS (
+			style.AttrBorder {
+				borderEngraved,
+				borderGap,
+				borderLiftedFocused,
+			},
+			style.AttrPadding(tomo.I(4, 8)),
+			style.AttrColor { Color: colorRaisedFocused },
+		),
+		Hovered: style.AS (
+			style.AttrColor { Color: colorRaisedHovered },
+		),
+	},
+
+	// *.TextInput[*]
+	style.Rule {
+		Role: tomo.R("", "TextInput", ""),
+		Default: style.AS (
+			style.AttrBorder {
+				borderEngraved,
+				borderGap,
+				borderInnerShadow,
+			},
+			style.AttrColor { Color: tomo.ColorSunken },
+			style.AttrPadding(tomo.I(5, 4, 4, 5)),
+		),
+		Focused: style.AS (
+			style.AttrBorder {
+				borderEngraved,
+				borderFocused,
+				borderInnerShadow,
+			},
+		),
+	},
+
+	// *.TextView[*]
+	style.Rule {
+		Role: tomo.R("", "TextView", ""),
+		Default: style.AS (
+			style.AttrBorder {
+				borderEngraved,
+				borderGap,
+				borderInnerShadow,
+			},
+			style.AttrColor { Color: tomo.ColorSunken },
+			style.AttrPadding(tomo.I(8)),
+		),
+	},
+	
+	// *.NumberInput[*]
+	style.Rule {
+		Role: tomo.R("", "NumberInput", ""),
+		Default: style.AS (
+			style.AttrGap { },
+		),
+	},
+
+	// *.Container[sunken]
+	style.Rule {
+		Role: tomo.R("", "Container", "sunken"),
+		Default: style.AS (
+			style.AttrBorder {
+				borderEngraved,
+				borderGap,
+				borderInnerShadow,
+			},
+			style.AttrColor { Color: tomo.ColorSunken },
+			style.AttrPadding(tomo.I(8)),
+		),
+	},
+
+	// *.Container[outer]
+	style.Rule {
+		Role: tomo.R("", "Container", "outer"),
+		Default: style.AS (
+			style.AttrColor { Color: tomo.ColorBackground },
+			style.AttrPadding(tomo.I(8)),
+		),
+	},
+
+	// *.Container[menu]
+	style.Rule {
+		Role: tomo.R("", "Container", "menu"),
+		Default: style.AS (
+			style.AttrBorder {
+				borderGap,
+				borderLifted,
+			},
+			style.AttrColor { Color: tomo.ColorBackground },
+			style.AttrGap { },
+		),
+	},
+
+	// *.Heading[*]
+	style.Rule {
+		Role: tomo.R("", "Heading", ""),
+		Default: style.AS (
+			style.AttrAlign { X: tomo.AlignMiddle, Y: tomo.AlignMiddle },
+		),
+	},
+
+	// *.Separator[*]
+	style.Rule {
+		Role: tomo.R("", "Separator", ""),
+		Default: style.AS (
+			style.AttrBorder {
+				borderEngraved,
+			},
+		),
+	},
+
+	// *.Slider[*]
+	style.Rule {
+		Role: tomo.R("", "Slider", ""),
+		Default: style.AS (
+			style.AttrBorder {
+				borderEngraved,
+				borderGap,
+				borderInnerShadow,
+			},
+			style.AttrColor { Color: colorGutter },
+		),
+		Focused: style.AS (
+			style.AttrBorder {
+				borderEngraved,
+				borderFocused,
+				borderInnerShadow,
+			},
+		),
+		Hovered: style.AS (
+			style.AttrColor { Color: colorGutterHovered },
+		),
+	},
+	
+	// *.Slider[horizontal]
+	style.Rule {
+		Role: tomo.R("", "Slider", "horizontal"),
+		Default: style.AS(style.AttrMinimumSize { X: 48 }),
+	},
+	
+	// *.Slider[vertical]
+	style.Rule {
+		Role: tomo.R("", "Slider", "vertical"),
+		Default: style.AS(style.AttrMinimumSize { Y: 48 }),
+	},
+
+	// *.SliderHandle[*]
+	style.Rule {
+		Role: tomo.R("", "SliderHandle", ""),
+		Default: style.AS (
+			style.AttrBorder {
+				borderOuterShadow,
+				borderGap,
+				borderLifted,
+			},
+			style.AttrColor { Color: tomo.ColorRaised },
+			style.AttrMinimumSize { X: 12, Y: 12, },
+		),
+	},
+
+	// *.Checkbox[*]
+	style.Rule {
+		Role: tomo.R("", "Checkbox", ""),
+		Default: style.AS (
+			style.AttrBorder {
+				borderEngraved,
+				borderGap,
+				borderInnerShadow,
+			},
+			style.AttrColor { Color: tomo.ColorSunken },
+			style.AttrPadding(tomo.I(0, 1, 1, 0)),
+			style.AttrMinimumSize { X: 19, Y: 19 },
+		),
+		Focused: style.AS (
+			style.AttrBorder {
+				borderEngraved,
+				borderFocused,
+				borderInnerShadow,
+			},
+			style.AttrPadding(tomo.I(0)),
+			style.AttrColor { Color: colorSunkenFocused },
+		),
+	},
+
+	// *.LabelCheckbox[*]
+	style.Rule {
+		Role: tomo.R("", "LabelCheckbox", ""),
+		Default: style.AS (
+			style.AttrGap { X: 8, Y: 8 },
+		),
+	},
+
+	// *.MenuItem[*]
+	style.Rule {
+		Role: tomo.R("", "MenuItem", ""),
+		Default: style.AS (
+			style.AttrPadding(tomo.I(4)),
+			style.AttrGap { X: 4, Y: 4 },
+			style.AttrColor { Color: color.Transparent },
+		),
+		Hovered: style.AS (
+			style.AttrColor { Color: colorDot },
+		),
+		Focused: style.AS (
+			style.AttrColor { Color: colorDot },
+		),
+	},
+
+	// *.File[*]
+	style.Rule {
+		Role: tomo.R("", "File", ""),
+		Default: style.AS (
+			style.AttrColor { Color: color.Transparent },
+		),
+		Focused: style.AS (
+			style.AttrColor { Color: colorDot },
+		),
+	},
+	
+	// *.TearLine[*]
+	style.Rule {
+		Role: tomo.R("", "TearLine", ""),
+		Default: style.AS (
+			style.AttrBorder {
+				borderTearPad,
+				borderTear,
+			},
+		),
+		Hovered: style.AS (
+			style.AttrBorder {
+				borderTearPadFocused,
+				borderTearFocused,
+			},
+		),
+		Focused: style.AS (
+			style.AttrBorder {
+				borderTearPadFocused,
+				borderTearFocused,
+			},
+		),
+	},
+	
+	// *.Calendar[*]
+	style.Rule {
+		Role: tomo.R("", "Calendar", ""),
+		Default: style.AS (
+			style.AttrBorder {
+				borderOuterShadow,
+				borderGap,
+			},
+			style.AttrColor { Color: tomo.ColorRaised },
+			style.AttrPadding(tomo.I(2)),
+			style.AttrGap { X: 2, Y: 2 },
+		),
+	},
+	
+	// *.CalendarGrid[*]
+	style.Rule {
+		Role: tomo.R("", "CalendarGrid", ""),
+		Default: style.AS (
+			style.AttrGap { X: 2, Y: 2 },
+		),
+	},
+	
+	// *.CalendarWeekdayHeader[*]
+	style.Rule {
+		Role: tomo.R("", "CalendarWeekdayHeader", ""),
+		Default: style.AS (
+			style.AttrPadding(tomo.I(2)),
+			style.AttrColor { Color: colorCalendarWeekdayHeader },
+		),
+	},
+	
+	// *.CalendarDay[weekday]
+	style.Rule {
+		Role: tomo.R("", "CalendarDay", "weekday"),
+		Default: style.AS (
+			style.AttrPadding(tomo.I(2)),
+			style.AttrMinimumSize { X: 32, Y: 32 },
+			style.AttrColor { Color: colorCalendarDay },
+		),
+	},
+
+	// *.CalendarDay[weekend]
+	style.Rule {
+		Role: tomo.R("", "CalendarDay", "weekend"),
+		Default: style.AS (
+			style.AttrPadding(tomo.I(2)),
+			style.AttrMinimumSize { X: 32, Y: 32 },
+			style.AttrColor { Color: colorCalendarWeekend },
+		),
+	},
+}

internal/style/attribute.go

@@ -0,0 +1,41 @@
+package style
+
+import "image"
+import "image/color"
+import "golang.org/x/image/font"
+import "git.tebibyte.media/tomo/tomo"
+
+// Attr modifies one thing about an Objects's style.
+type Attr interface { attr () int }
+
+// AttrColor sets the background color of an Objects.
+type AttrColor struct { color.Color }
+// AttrTexture sets the texture of an Objects to a named texture.
+type AttrTexture string
+// AttrBorder sets the border of an Objects.
+type AttrBorder []tomo.Border
+// AttrMinimumSize sets the minimum size of an Objects.
+type AttrMinimumSize image.Point
+// AttrPadding sets the inner padding of an Objects.
+type AttrPadding tomo.Inset
+// AttrGap sets the gap between child Objects, if the Object is a ContainerBox.
+type AttrGap image.Point
+// AttrTextColor sets the text color, if the Object is a TextBox.
+type AttrTextColor struct { color.Color }
+// AttrDotColor sets the text selection color, if the Object is a TextBox.
+type AttrDotColor struct { color.Color }
+// AttrFace sets the font face, if the Object is a TextBox.
+type AttrFace struct { font.Face }
+// AttrAlign sets the alignment, if the Object is a ContentBox.
+type AttrAlign struct { X, Y tomo.Align }
+
+func (AttrColor)       attr () int { return 0 }
+func (AttrTexture)     attr () int { return 1 }
+func (AttrBorder)      attr () int { return 2 }
+func (AttrMinimumSize) attr () int { return 3 }
+func (AttrPadding)     attr () int { return 4 }
+func (AttrGap)         attr () int { return 5 }
+func (AttrTextColor)   attr () int { return 6 }
+func (AttrDotColor)    attr () int { return 7 }
+func (AttrFace)        attr () int { return 8 }
+func (AttrAlign)       attr () int { return 9 }

internal/style/fallback/style.go

@@ -0,0 +1,558 @@
+package fallbackStyle
+
+import "image/color"
+import "git.tebibyte.media/tomo/tomo"
+import "golang.org/x/image/font/basicfont"
+import "git.tebibyte.media/tomo/nasin/internal/style"
+
+var colorFocus                 = color.RGBA { R:  61, G: 128, B: 143, A: 255 }
+var colorInput                 = color.RGBA { R: 208, G: 203, B: 150, A: 255 }
+var colorCarved                = color.RGBA { R: 151, G: 160, B: 150, A: 255 }
+var colorGutter                = color.RGBA { R: 116, G: 132, B: 126, A: 255 }
+var colorShadow                = color.RGBA { R:  57, G:  59, B:  57, A: 255 }
+var colorShade                 = color.RGBA {                         A: 128 }
+var colorInputShadow           = color.RGBA { R: 143, G: 146, B:  91, A: 255 }
+var colorHighlight             = color.RGBA { R: 207, G: 215, B: 210, A: 255 }
+var colorBackground            = color.RGBA { R: 169, G: 171, B: 168, A: 255 }
+var colorCarvedPressed         = color.RGBA { R: 129, G: 142, B: 137, A: 255 }
+var colorForeground            = color.Black
+var colorOutline               = color.Black
+var colorCalendarWeekdayHeader = color.RGBA { R: 194, G: 162, B: 132, A: 255 }
+var colorCalendarWeekend       = color.RGBA { R: 165, G: 185, B: 120, A: 255 }
+var colorCalendarDay           = color.RGBA { R: 194, G: 189, B: 132, A: 255 }
+var colorInactive              = color.RGBA { R: 131, G: 147, B: 134, A: 255 }
+
+var outline = tomo.Border {
+	Width: tomo.I(1),
+	Color: [4]color.Color {
+		colorOutline,
+		colorOutline,
+		colorOutline,
+		colorOutline,
+	},
+}
+
+var borderColorOutline  = [4]color.Color { colorOutline,     colorOutline,   colorOutline,   colorOutline     }
+var borderColorEngraved = [4]color.Color { colorShadow,      colorHighlight, colorHighlight, colorShadow      }
+var borderColorLifted   = [4]color.Color { colorHighlight,   colorShadow,    colorShadow,    colorHighlight   }
+var borderColorInput    = [4]color.Color { colorInputShadow, colorInput,     colorInput,     colorInputShadow }
+var borderColorFocused  = [4]color.Color { colorFocus,       colorFocus,     colorFocus,     colorFocus       }
+var borderColorShade    = [4]color.Color { colorShade,       colorShade,     colorShade,     colorShade       }
+
+var rules = []style.Rule {
+	// *.*[*]
+	style.Rule {
+		Default: style.AS (
+			style.AttrFace      { Face:  basicfont.Face7x13    },
+			style.AttrTextColor { Color: tomo.ColorForeground  },
+			style.AttrDotColor  { Color: tomo.ColorAccent      },
+			style.AttrGap       { X: 8, Y: 8                   },
+		),
+	},
+
+	// *.Button[*]
+	style.Rule {
+		Role: tomo.R("", "Button", ""),
+		Default: style.AS (
+			style.AttrBorder {
+				outline,
+				tomo.Border {
+					Width: tomo.I(1),
+					Color: borderColorLifted,
+				},
+			},
+			style.AttrPadding(tomo.I(4, 8)),
+			style.AttrColor { Color: tomo.ColorRaised },
+		),
+		Pressed: style.AS (
+			style.AttrBorder {
+				outline,
+				tomo.Border {
+					Width: tomo.I(1, 0, 0, 1),
+					Color: borderColorEngraved,
+				},
+			},
+			style.AttrPadding(tomo.I(5, 8, 4, 9)),
+			style.AttrColor { Color: colorCarvedPressed },
+		),
+		Focused: style.AS (
+			style.AttrBorder {
+				outline,
+				tomo.Border {
+					Width: tomo.I(1),
+					Color: borderColorFocused,
+				},
+			},
+			style.AttrPadding(tomo.I(4, 8)),
+		),
+	},
+
+	// *.TextInput[*]
+	style.Rule {
+		Role: tomo.R("", "TextInput", ""),
+		Default: style.AS (
+			style.AttrBorder {
+				outline,
+				tomo.Border {
+					Width: tomo.I(1),
+					Color: borderColorInput,
+				},
+			},
+			style.AttrColor { Color: colorInput },
+			style.AttrPadding(tomo.I(5, 4, 4, 5)),
+		),
+		Focused: style.AS (
+			style.AttrBorder {
+				outline,
+				tomo.Border {
+					Width: tomo.I(1),
+					Color: borderColorFocused,
+				},
+			},
+		),
+	},
+
+	// *.TextView[*]
+	style.Rule {
+		Role: tomo.R("", "TextView", ""),
+		Default: style.AS (
+			style.AttrBorder {
+				outline,
+				tomo.Border {
+					Width: tomo.I(1, 0, 0, 1),
+					Color: borderColorEngraved,
+				},
+			},
+			style.AttrColor { Color: tomo.ColorSunken },
+			style.AttrPadding(tomo.I(8)),
+		),
+	},
+	
+	// *.NumberInput[*]
+	style.Rule {
+		Role: tomo.R("", "NumberInput", ""),
+		Default: style.AS (
+			style.AttrGap { },
+		),
+	},
+
+	// *.Container[sunken]
+	style.Rule {
+		Role: tomo.R("", "Container", "sunken"),
+		Default: style.AS (
+			style.AttrBorder {
+				outline,
+				tomo.Border {
+					Width: tomo.I(1, 0, 0, 1),
+					Color: borderColorEngraved,
+				},
+			},
+			style.AttrColor { Color: tomo.ColorSunken },
+			style.AttrPadding(tomo.I(8)),
+		),
+	},
+
+	// *.Container[outer]
+	style.Rule {
+		Role: tomo.R("", "Container", "outer"),
+		Default: style.AS (
+			style.AttrColor { Color: tomo.ColorBackground },
+			style.AttrPadding(tomo.I(8)),
+		),
+	},
+
+	// *.Container[menu]
+	style.Rule {
+		Role: tomo.R("", "Container", "menu"),
+		Default: style.AS (
+			style.AttrBorder {
+				outline,
+				tomo.Border {
+					Width: tomo.I(1),
+					Color: borderColorLifted,
+				},
+			},
+			style.AttrColor { Color: tomo.ColorBackground },
+			style.AttrGap { },
+		),
+	},
+
+	// *.Heading[*]
+	style.Rule {
+		Role: tomo.R("", "Heading", ""),
+		Default: style.AS (
+			style.AttrAlign { X: tomo.AlignMiddle, Y: tomo.AlignMiddle },
+		),
+	},
+
+	// *.Separator[*]
+	style.Rule {
+		Role: tomo.R("", "Separator", ""),
+		Default: style.AS (
+			style.AttrBorder {
+				tomo.Border {
+					Width: tomo.I(1),
+					Color: borderColorEngraved,
+				},
+			},
+		),
+	},
+
+	// *.Slider[*]
+	style.Rule {
+		Role: tomo.R("", "Slider", ""),
+		Default: style.AS (
+			style.AttrBorder {
+				outline,
+				tomo.Border {
+					Width: tomo.I(1, 0, 0, 1),
+					Color: borderColorEngraved,
+				},
+			},
+			style.AttrColor { Color: colorGutter },
+			style.AttrPadding(tomo.I(0, 1, 1, 0)),
+		),
+		Focused: style.AS (
+			style.AttrBorder {
+				outline,
+				tomo.Border {
+					Width: tomo.I(1),
+					Color: borderColorFocused,
+				},
+			},
+			style.AttrPadding(tomo.I(0)),
+		),
+	},
+	
+	// *.Slider[horizontal]
+	style.Rule {
+		Role: tomo.R("", "Slider", "horizontal"),
+		Default: style.AS(style.AttrMinimumSize { X: 48 }),
+	},
+	
+	// *.Slider[vertical]
+	style.Rule {
+		Role: tomo.R("", "Slider", "vertical"),
+		Default: style.AS(style.AttrMinimumSize { Y: 48 }),
+	},
+
+	// *.SliderHandle[*]
+	style.Rule {
+		Role: tomo.R("", "SliderHandle", ""),
+		Default: style.AS (
+			style.AttrBorder {
+				outline,
+				tomo.Border {
+					Width: tomo.I(1),
+					Color: borderColorLifted,
+				},
+			},
+			style.AttrColor { Color: tomo.ColorRaised },
+			style.AttrMinimumSize { X: 12, Y: 12, },
+		),
+	},
+
+	// *.Checkbox[*]
+	style.Rule {
+		Role: tomo.R("", "Checkbox", ""),
+		Default: style.AS (
+			style.AttrBorder {
+				outline,
+				tomo.Border {
+					Width: tomo.I(1, 0, 0, 1),
+					Color: borderColorEngraved,
+				},
+			},
+			style.AttrColor { Color: tomo.ColorSunken },
+			style.AttrPadding(tomo.I(0, 1, 1, 0)),
+			style.AttrMinimumSize { X: 19, Y: 19 },
+		),
+		Focused: style.AS (
+			style.AttrBorder {
+				outline,
+				tomo.Border {
+					Width: tomo.I(1),
+					Color: borderColorFocused,
+				},
+			},
+			style.AttrPadding(tomo.I(0)),
+		),
+	},
+
+	// *.MenuItem[*]
+	style.Rule {
+		Role: tomo.R("", "MenuItem", ""),
+		Default: style.AS (
+			style.AttrPadding(tomo.I(4)),
+			style.AttrGap { X: 4, Y: 4 },
+			style.AttrColor { Color: color.Transparent },
+		),
+		Hovered: style.AS (
+			style.AttrColor { Color: tomo.ColorAccent },
+		),
+		Focused: style.AS (
+			style.AttrColor { Color: tomo.ColorAccent },
+		),
+	},
+
+	// *.File[*]
+	style.Rule {
+		Role: tomo.R("", "File", ""),
+		Default: style.AS (
+			style.AttrColor { Color: color.Transparent },
+		),
+		Focused: style.AS (
+			style.AttrColor { Color: tomo.ColorAccent },
+		),
+	},
+
+	// *.TearLine[*]
+	style.Rule {
+		Role: tomo.R("", "TearLine", ""),
+		Default: style.AS (
+			style.AttrBorder {
+				tomo.Border {
+					Width: tomo.I(3),
+					Color: [4]color.Color {
+						color.Transparent,
+						color.Transparent,
+						color.Transparent,
+						color.Transparent,
+					},
+				},
+			},
+			style.AttrColor { Color: tomo.ColorForeground },
+			style.AttrPadding(tomo.I(1, 0, 0, 1)),
+		),
+		Hovered: style.AS (
+			style.AttrBorder {
+				tomo.Border {
+					Width: tomo.I(3),
+					Color: borderColorFocused,
+				},
+			},
+		),
+		Focused: style.AS (
+			style.AttrBorder {
+				tomo.Border {
+					Width: tomo.I(3),
+					Color: borderColorFocused,
+				},
+			},
+		),
+	},
+	
+	// *.Calendar[*]
+	style.Rule {
+		Role: tomo.R("", "Calendar", ""),
+		Default: style.AS (
+			style.AttrBorder {
+				tomo.Border {
+					Width: tomo.I(0, 1, 1, 0),
+					Color: borderColorShade,
+				},
+				outline,
+			},
+			style.AttrColor { Color: colorInput },
+			style.AttrPadding(tomo.I(2)),
+			style.AttrGap { X: 2, Y: 2 },
+		),
+	},
+	
+	// *.CalendarGrid[*]
+	style.Rule {
+		Role: tomo.R("", "CalendarGrid", ""),
+		Default: style.AS (
+			style.AttrGap { X: 2, Y: 2 },
+		),
+	},
+	
+	// *.CalendarWeekdayHeader[*]
+	style.Rule {
+		Role: tomo.R("", "CalendarWeekdayHeader", ""),
+		Default: style.AS (
+			style.AttrPadding(tomo.I(2)),
+			style.AttrColor { Color: colorCalendarWeekdayHeader },
+		),
+	},
+	
+	// *.CalendarDay[weekday]
+	style.Rule {
+		Role: tomo.R("", "CalendarDay", "weekday"),
+		Default: style.AS (
+			style.AttrPadding(tomo.I(2)),
+			style.AttrMinimumSize { X: 32, Y: 32 },
+			style.AttrColor { Color: colorCalendarDay },
+		),
+	},
+
+	// *.CalendarDay[weekend]
+	style.Rule {
+		Role: tomo.R("", "CalendarDay", "weekend"),
+		Default: style.AS (
+			style.AttrPadding(tomo.I(2)),
+			style.AttrMinimumSize { X: 32, Y: 32 },
+			style.AttrColor { Color: colorCalendarWeekend },
+		),
+	},
+	
+	// *.TabbedContainer[*]
+	style.Rule {
+		Role: tomo.R("", "TabbedContainer", ""),
+		Default: style.AS (
+			style.AttrGap { },
+		),
+	},
+	
+	// *.TabRow[*]
+	style.Rule {
+		Role: tomo.R("", "TabRow", ""),
+		Default: style.AS (
+			style.AttrBorder {
+				tomo.Border {
+					Width: tomo.I(1, 1, 0, 1),
+					Color: borderColorOutline,
+				},
+				tomo.Border {
+					Width: tomo.I(1, 0, 0, 1),
+					Color: borderColorEngraved,
+				},
+			},
+			style.AttrGap { X: 0, Y: 0 },
+			style.AttrColor { Color: colorGutter },
+			style.AttrPadding(tomo.I(1, 0, 0, 0)),
+		),
+	},
+	
+	// *.TabSpacer[left]
+	style.Rule {
+		Role: tomo.R("", "TabSpacer", "left"),
+		Default: style.AS (
+			style.AttrBorder {
+				tomo.Border {
+					Width: tomo.I(0, 0, 1, 0),
+					Color: borderColorEngraved,
+				},
+				tomo.Border {
+					Width: tomo.I(0, 0, 1, 0),
+					Color: borderColorOutline,
+				},
+			},
+			style.AttrMinimumSize { X: 1 },
+		),
+	},
+	
+	// *.TabSpacer[right]
+	style.Rule {
+		Role: tomo.R("", "TabSpacer", "right"),
+		Default: style.AS (
+			style.AttrBorder {
+				tomo.Border {
+					Width: tomo.I(1, 0, 0, 0),
+					Color: [4]color.Color {
+						colorGutter, colorGutter,
+						colorGutter, colorGutter,
+					},
+				},
+				tomo.Border {
+					Width: tomo.I(0, 0, 1, 0),
+					Color: borderColorEngraved,
+				},
+				tomo.Border {
+					Width: tomo.I(0, 0, 1, 1),
+					Color: borderColorOutline,
+				},
+				tomo.Border {
+					Width: tomo.I(0, 0, 0, 1),
+					Color: borderColorShade,
+				},
+			},
+			style.AttrMinimumSize { X: 3 },
+		),
+	},
+	
+	// *.Tab[*]
+	style.Rule {
+		Role: tomo.R("", "Tab", ""),
+		Default: style.AS (
+			style.AttrBorder {
+				tomo.Border {
+					Width: tomo.I(1, 0, 0, 0),
+					Color: [4]color.Color {
+						colorGutter, colorGutter,
+						colorGutter, colorGutter,
+					},
+				},
+				tomo.Border {
+					Width: tomo.I(0, 0, 1, 0),
+					Color: borderColorEngraved,
+				},
+				tomo.Border {
+					Width: tomo.I(1, 0, 1, 1),
+					Color: borderColorOutline,
+				},
+				tomo.Border {
+					Width: tomo.I(1, 1, 0, 1),
+					Color: borderColorLifted,
+				},
+			},
+			style.AttrPadding(tomo.I(4, 8, 4, 8)),
+			style.AttrColor { Color: tomo.ColorRaised },
+		),
+	},
+	
+	// *.Tab[active]
+	style.Rule {
+		Role: tomo.R("", "Tab", "active"),
+		Default: style.AS (
+			style.AttrBorder {
+				tomo.Border {
+					Width: tomo.I(1, 0, 0, 1),
+					Color: borderColorOutline,
+				},
+				tomo.Border {
+					Width: tomo.I(1, 1, 0, 1),
+					Color: borderColorLifted,
+				},
+			},
+			style.AttrPadding(tomo.I(4, 8, 4, 8)),
+			style.AttrColor { Color: tomo.ColorBackground },
+		),
+	},
+
+	// *.Swatch[*]
+	style.Rule {
+		Role: tomo.R("", "Swatch", ""),
+		Default: style.AS (
+			style.AttrBorder {
+				outline,
+			},
+			style.AttrMinimumSize { X: 19, Y: 19 },
+		),
+		Focused: style.AS (
+			style.AttrBorder {
+				outline,
+				tomo.Border {
+					Width: tomo.I(1),
+					Color: borderColorFocused,
+				},
+			},
+		),
+	},
+
+	// *.ColorPickerMap[*]
+	style.Rule {
+		Role: tomo.R("", "ColorPickerMap", ""),
+		Default: style.AS (
+			style.AttrBorder {
+				outline,
+				tomo.Border {
+					Width: tomo.I(1, 0, 0, 1),
+					Color: borderColorEngraved,
+				},
+			},
+			style.AttrColor { Color: tomo.ColorSunken },
+			style.AttrMinimumSize { X: 128, Y: 128 },
+		),
+	},
+}

internal/style/fallback/wintergreen.go

@@ -0,0 +1,20 @@
+package fallbackStyle
+
+import "image/color"
+import "git.tebibyte.media/tomo/tomo"
+import "git.tebibyte.media/tomo/nasin/internal/style"
+
+// New returns Wintergreen, the default Tomo style. It is neutral-gray with
+// green and turquoise accents.
+func New () *style.Style {
+	return &style.Style {
+		Colors: map[tomo.Color] color.Color {
+			tomo.ColorBackground: colorBackground,
+			tomo.ColorForeground: colorForeground,
+			tomo.ColorRaised:     colorCarved,
+			tomo.ColorSunken:     colorCarved,
+			tomo.ColorAccent:     colorFocus,
+		},
+		Rules: rules,
+	}
+}

internal/style/missing.go

@@ -0,0 +1,24 @@
+package style
+
+import "image"
+import "image/color"
+
+type missingTexture int
+
+func (texture missingTexture) ColorModel () color.Model {
+	return color.RGBAModel
+}
+
+func (texture missingTexture) Bounds () image.Rectangle {
+	return image.Rect(0, 0, int(texture), int(texture))
+}
+
+func (texture missingTexture) At (x, y int) color.Color {
+	x /= 8
+	y /= 8
+	if (x + y) % 2 == 0 {
+		return color.RGBA { R: 0xFF, B: 0xFF, A: 0xFF }
+	} else {
+		return color.RGBA { A: 0xFF }
+	}
+}

internal/style/style.go

@@ -0,0 +1,239 @@
+// Package style provides a data-driven style implementation.
+package style
+
+import "image"
+import "image/color"
+import "git.tebibyte.media/tomo/tomo"
+import "git.tebibyte.media/tomo/tomo/event"
+import "git.tebibyte.media/tomo/tomo/input"
+import "git.tebibyte.media/tomo/tomo/canvas"
+
+// this is CSS's bastard child
+
+// Style allows the use of data to define a visual style.
+type Style struct {
+	// Textures maps texture names to image textures.
+	Textures map[string] image.Image
+	textures map[string] canvas.TextureCloser // private texture cache
+	missing  canvas.TextureCloser             // cache for "missing" texture
+	
+	// Rules determines which styles get applied to which Objects.
+	Rules []Rule
+
+	// Colors maps tomo.Color values to color.RGBA values.
+	Colors map[tomo.Color] color.Color
+}
+
+// Rule describes under what circumstances should certain style attributes be
+// active.
+type Rule struct {
+	Role tomo.Role
+	Default AttrSet
+	Hovered AttrSet
+	Pressed AttrSet
+	Focused AttrSet
+}
+
+// AttrSet is a set of attributes wherein only one/zero of each attribute type
+// can exist. I deserve to be imprisoned for the way I made this work (look in
+// attribute.go). Its zero value can be used safely, and you can copy it if you
+// want, but it will point to the same set of attributes.
+type AttrSet struct {
+	set map[int] Attr
+}
+
+// AS builds an AttrSet out of a vararg list of Attr values.
+func AS (attrs ...Attr) AttrSet {
+	set := AttrSet { }
+	set.Add(attrs...)
+	return set
+}
+
+// Add adds attributes to the set.
+func (this *AttrSet) Add (attrs ...Attr) {
+	this.ensure()
+	for _, attr := range attrs {
+		this.set[attr.attr()] = attr
+	}
+}
+
+// MergeUnder takes attributes from another set and adds them if they don't
+// already exist in this one.
+func (this *AttrSet) MergeUnder (other AttrSet) {
+	this.ensure()
+	if other.set == nil { return }
+	for _, attr := range other.set {
+		if _, exists := this.set[attr.attr()]; !exists {
+			this.Add(attr)
+		}
+	}
+}
+
+// MergeOver takes attributes from another set and adds them, overriding this
+// one.
+func (this *AttrSet) MergeOver (other AttrSet) {
+	this.ensure()
+	if other.set == nil { return }
+	for _, attr := range other.set {
+		this.Add(attr)
+	}
+}
+
+func (this *AttrSet) ensure () {
+	if this.set == nil { this.set = make(map[int] Attr) }
+}
+
+func (this *Style) execute (object tomo.Object, set AttrSet) {
+	box := object.GetBox()
+	
+	for _, attr := range set.set {
+		switch attr := attr.(type) {
+		case AttrColor:
+			box.SetColor(attr.Color)
+		case AttrTexture:
+			box.SetTextureTile(this.texture(string(attr)))
+		case AttrBorder:
+			box.SetBorder([]tomo.Border(attr)...)
+		case AttrMinimumSize:
+			box.SetMinimumSize(image.Point(attr))
+		case AttrPadding:
+			box.SetPadding(tomo.Inset(attr))
+		case AttrGap:
+			if box, ok := box.(tomo.ContainerBox); ok {
+				box.SetGap(image.Point(attr))
+			}
+		case AttrTextColor:
+			if box, ok := box.(tomo.TextBox); ok {
+				box.SetTextColor(attr.Color)
+			}
+		case AttrDotColor:
+			if box, ok := box.(tomo.TextBox); ok {
+				box.SetDotColor(attr.Color)
+			}
+		case AttrFace:
+			if box, ok := box.(tomo.TextBox); ok {
+				box.SetFace(attr)
+			}
+		case AttrAlign:
+			if box, ok := box.(tomo.ContentBox); ok {
+				box.SetAlign(attr.X, attr.Y)
+			}
+		default:
+			panic("bug: nasin/internal/tomo.Theme: unexpected attribute")
+		}
+	}
+}
+
+func (this *Style) texture (name string) canvas.Texture {
+	this.ensureTextureCache()
+	if texture, ok := this.textures[name]; ok {
+		return texture
+	}
+	if this.Textures == nil {
+		if source, ok := this.Textures[name]; ok {
+			texture := tomo.NewTexture(source)
+			this.textures[name] = texture
+			return texture
+		}
+	}
+	return this.missingTexture()
+}
+
+func (this *Style) missingTexture () canvas.Texture {
+	if this.missing == nil {
+		this.missing = tomo.NewTexture(missingTexture(16))
+	}
+	return this.missing
+}
+
+func (this *Style) ensureTextureCache () {
+	if this.textures == nil { this.textures = make(map[string] canvas.TextureCloser) }
+}
+
+// setsFor builds flattened attr sets for a specific role based on the rules list
+func (this *Style) setsFor (role tomo.Role) (defaul, hovered, pressed, focused AttrSet) {
+	for _, current := range this.Rules {
+		// check for a match
+		packageMatch := current.Role.Package == role.Package || current.Role.Package == ""
+		objectMatch  := current.Role.Object  == role.Object  || current.Role.Object  == ""
+		variantMatch := current.Role.Variant == role.Variant || current.Role.Variant == ""
+		if packageMatch && objectMatch && variantMatch {
+			// if found, merge and override
+			defaul.MergeOver(current.Default)
+			hovered.MergeOver(current.Hovered)
+			pressed.MergeOver(current.Pressed)
+			focused.MergeOver(current.Focused)
+		}
+	}
+
+	// hovered and pressed are mutually exclusive states, so we compress
+	// them with the default state.
+	hovered.MergeUnder(defaul)
+	pressed.MergeUnder(defaul)
+	return defaul, hovered, pressed, focused
+}
+
+func (this *Style) Apply (object tomo.Object) event.Cookie {
+	pressed := false
+	hovered := false
+	box  := object.GetBox()
+	role := box.Role()
+
+	defaultSet, hoveredSet, pressedSet, focusedSet := this.setsFor(role)
+
+	updateStyle := func () {
+		if pressed {
+			this.execute(object, pressedSet)
+		} else if hovered {
+			this.execute(object, hoveredSet)
+		} else {
+			this.execute(object, defaultSet)
+		}
+		if box.Focused() && !pressed {
+			this.execute(object, focusedSet)
+		}
+	}
+	updateStyle()
+	
+	return event.MultiCookie (
+		box.OnFocusEnter(updateStyle),
+		box.OnFocusLeave(updateStyle),
+		box.OnMouseDown(func (button input.Button) {
+			if button != input.ButtonLeft { return }
+			pressed = true
+			updateStyle()
+		}),
+		box.OnMouseUp(func (button input.Button) {
+			if button != input.ButtonLeft { return }
+			pressed = false
+			updateStyle()
+		}),
+		box.OnMouseEnter(func () {
+			hovered = true
+			updateStyle()
+		}),
+		box.OnMouseLeave(func () {
+			hovered = false
+			updateStyle()
+		}))
+
+}
+
+func (this *Style) RGBA (c tomo.Color) (r, g, b, a uint32) {
+	if this.Colors == nil { return 0xFFFF, 0, 0xFFFF, 0xFFFF }
+	color, ok := this.Colors[c]
+	if !ok { return 0xFFFF, 0, 0xFFFF, 0xFFFF }
+	return color.RGBA()
+}
+
+// Close closes all cached textures this style has open. Do not call this while
+// the style is in use.
+func (this *Style) Close () error {
+	this.missing.Close()
+	this.missing = nil
+	for _, texture := range this.textures {
+		texture.Close()
+	}
+	this.textures = nil
+	return nil
+}

path.go

@@ -1,190 +1,32 @@
 package nasin
 
-import "io"
 import "os"
-import "io/fs"
-import "strings"
 import "path/filepath"
 
-// FS is Tomo's implementation of fs.FS. It provides access to a specific part
-// of the filesystem.
-type FS struct {
-	path string
+// ApplicationUserDataDir returns the directory path where an application can
+// store its user data files. If the directory does not exist, it will be
+// created.
+func ApplicationUserDataDir (app ApplicationDescription) (string, error) {
+	return userMkdirAll(app.ID, userDataDir)
 }
 
-// FileWriter is a writable version of fs.File.
-type FileWriter interface {
-	fs.File
-	io.Writer
+// ApplicationUserConfigDir returns the directory path where an application can
+// store its user configuration files.
+func ApplicationUserConfigDir (app ApplicationDescription) (string, error) {
+	return userMkdirAll(app.ID, userConfigDir)
 }
 
-// ApplicationUserDataFS returns an FS that an application can use to store user
-// data files.
-func ApplicationUserDataFS (app ApplicationDescription) (*FS, error) {
-	dataDir, err := userDataDir()
-	if err != nil { return nil, err }
-	return appFs(dataDir, app)
+// ApplicationUserCacheDir returns the directory path where an application can
+// store its user cache files.
+func ApplicationUserCacheDir (app ApplicationDescription) (string, error) {
+	return userMkdirAll(app.ID, userCacheDir)
 }
 
-// ApplicationUserConfigFS returns an FS that an application can use to store
-// user configuration files.
-func ApplicationUserConfigFS (app ApplicationDescription) (*FS, error) {
-	configDir, err := userConfigDir()
-	if err != nil { return nil, err }
-	return appFs(configDir, app)
-}
-
-// ApplicationUserCacheFS returns an FS that an application can use to store
-// user cache files.
-func ApplicationUserCacheFS (app ApplicationDescription) (*FS, error) {
-	cacheDir, err := userCacheDir()
-	if err != nil { return nil, err }
-	return appFs(cacheDir, app)
-}
-
-func pathErr (op, path string, err error) error {
-	return &fs.PathError {
-		Op:   op,
-		Path: path,
-		Err:  err,
-	}
-}
-
-func appFs (root string, app ApplicationDescription) (*FS, error) {
-	// remove slashes
-	appid := app.ID
-	appid = strings.ReplaceAll(appid, "/", "-")
-	appid = strings.ReplaceAll(appid, "\\", "-")
-
-	path := filepath.Join(root, appid)
-
-	// ensure the directory actually exists
-	err := os.MkdirAll(path, 700)
-	if err != nil { return nil, err }
-
-	return &FS { path: path }, nil
-}
-
-func (this FS) subPath (name string) (string, error) {
-	if !fs.ValidPath(name)         { return "", fs.ErrInvalid }
-	if strings.Contains(name, "/") { return "", fs.ErrInvalid }
-	return filepath.Join(this.path, name), nil
-}
-
-// Open opens the named file.
-func (this FS) Open (name string) (fs.File, error) {
-	path, err := this.subPath(name)
-	if err != nil {
-		return nil, pathErr("open", name, err)
-	}
-
-	return os.Open(path)
-}
-
-// Create creates or truncates the named file.
-func (this FS) Create (name string) (FileWriter, error) {
-	path, err := this.subPath(name)
-	if err != nil {
-		return nil, pathErr("create", name, err)
-	}
-
-	return os.Create(path)
-}
-
-// OpenFile is the generalized open call; most users will use Open or Create
-// instead.
-func (this FS) OpenFile (
-	name string,
-	flag int,
-	perm os.FileMode,
-) (
-	FileWriter,
-	error,
-) {
-	path, err := this.subPath(name)
-	if err != nil {
-		return nil, pathErr("open", name, err)
-	}
-
-	return os.OpenFile(path, flag, perm)
-}
-
-// ReadDir reads the named directory and returns a list of directory entries
-// sorted by filename.
-func (this FS) ReadDir (name string) ([]fs.DirEntry, error) {
-	path, err := this.subPath(name)
-	if err != nil {
-		return nil, pathErr("readdir", name, err)
-	}
-
-	return os.ReadDir(path)
-}
-
-// ReadFile reads the named file and returns its contents.
-// A successful call returns a nil error, not io.EOF.
-// (Because ReadFile reads the whole file, the expected EOF
-// from the final Read is not treated as an error to be reported.)
-//
-// The caller is permitted to modify the returned byte slice.
-func (this FS) ReadFile (name string) ([]byte, error) {
-	path, err := this.subPath(name)
-	if err != nil {
-		return nil, pathErr("readfile", name, err)
-	}
-
-	return os.ReadFile(path)
-}
-
-// WriteFile writes data to the named file, creating it if necessary.
-func (this FS) WriteFile (name string, data []byte, perm os.FileMode) error {
-	path, err := this.subPath(name)
-	if err != nil {
-		return pathErr("writefile", name, err)
-	}
-
-	return os.WriteFile(path, data, perm)
-}
-
-// Stat returns a FileInfo describing the file.
-func (this FS) Stat (name string) (fs.FileInfo, error) {
-	path, err := this.subPath(name)
-	if err != nil {
-		return nil, pathErr("stat", name, err)
-	}
-
-	return os.Stat(path)
-}
-
-// Remove removes the named file or (empty) directory.
-func (this FS) Remove (name string) error {
-	path, err := this.subPath(name)
-	if err != nil {
-		return pathErr("remove", name, err)
-	}
-
-	return os.Remove(path)
-}
-
-// RemoveAll removes name and any children it contains.
-func (this FS) RemoveAll (name string) error {
-	path, err := this.subPath(name)
-	if err != nil {
-		return pathErr("removeall", name, err)
-	}
-
-	return os.RemoveAll(path)
-}
-
-// Rename renames (moves) oldname to newname.
-func (this FS) Rename (oldname, newname string) error {
-	oldpath, err := this.subPath(oldname)
-	if err != nil {
-		return pathErr("rename", oldname, err)
-	}
-	newpath, err := this.subPath(newname)
-	if err != nil {
-		return pathErr("rename", newname, err)
-	}
-
-	return os.Rename(oldpath, newpath)
+func userMkdirAll (sub string, getter func () (string, error)) (string, error) {
+	path, err := getter()
+	if err != nil { return "", err }
+	path = filepath.Join(path, sub)
+	err = os.MkdirAll(path, 0700)
+	if err != nil { return "", err }
+	return path, nil
 }