Instruct themes to return nil icons if the icon doesn't exist

It was a bad idea. Remedy #12.

.editorconfig

@@ -0,0 +1,12 @@
+root = true
+
+[*]
+end_of_line = lf
+insert_final_newline = true
+indent_style = tab
+indent_size = 8
+charset = utf-8
+
+[*.md]
+indent_style = space
+indent_size = 2

README.md

@@ -2,4 +2,7 @@
 
 [![Go Reference](https://pkg.go.dev/badge/git.tebibyte.media/tomo/tomo.svg)](https://pkg.go.dev/git.tebibyte.media/tomo/tomo)
 
-Tomo is a lightweight GUI toolkit written in pure Go.
+Tomo is a lightweight GUI toolkit written in pure Go. This repository defines
+the API that other components of the toolkit agree on. In order to use Tomo in
+an application, use [Nasin](https://git.tebibyte.media/tomo/nasin), which builds
+an application framework on top of Tomo.

application.go

@@ -1,113 +0,0 @@
-package tomo
-
-import "image"
-
-// Application represents an application object.
-type Application interface {
-	// Describe returns a description of the application.
-	Describe () ApplicationDescription
-
-	// Init performs the initial setup of the application.
-	Init ()
-}
-
-// ApplicationDescription describes the name and type of an application.
-type ApplicationDescription struct {
-	// The name or ID of the application.
-	Name string
-
-	// Role describes what the application does.
-	Role ApplicationRole
-}
-
-// String satisfies the fmt.Stringer interface.
-func (application ApplicationDescription) String () string {
-	if application.Name == "" {
-		return application.Role.String()
-	} else {
-		return application.Name
-	}
-}
-
-// ApplicationRole describes what an application does.
-type ApplicationRole int; const (
-	RoleUnknown ApplicationRole = iota
-
-	RoleWebBrowser
-	RoleMesssanger
-	RolePhone
-	RoleMail
-
-	RoleTerminalEmulator
-	RoleFileBrowser
-	RoleTextEditor
-
-	RoleDocumentViewer
-	RoleWordProcessor
-	RoleSpreadsheet
-	RoleSlideshow
-	RoleCalculator
-
-	RolePreferences
-	RoleProcessManager
-	RoleSystemInformation
-	RoleManual
-
-	RoleCamera
-	RoleImageViewer
-	RoleMediaPlayer
-	RoleImageEditor
-	RoleAudioEditor
-	RoleVideoEditor
-
-	RoleClock
-	RoleCalendar
-	RoleChecklist
-)
-
-// String satisfies the fmt.Stringer interface.
-func (role ApplicationRole) String () string {
-	switch role {
-	case RoleWebBrowser:        return "Web Browser"
-	case RoleMesssanger:        return "Messsanger"
-	case RolePhone:             return "Phone"
-	case RoleMail:              return "Mail"
-	case RoleTerminalEmulator:  return "Terminal Emulator"
-	case RoleFileBrowser:       return "File Browser"
-	case RoleTextEditor:        return "Text Editor"
-	case RoleDocumentViewer:    return "Document Viewer"
-	case RoleWordProcessor:     return "Word Processor"
-	case RoleSpreadsheet:       return "Spreadsheet"
-	case RoleSlideshow:         return "Slideshow"
-	case RoleCalculator:        return "Calculator"
-	case RolePreferences:       return "Preferences"
-	case RoleProcessManager:    return "Process Manager"
-	case RoleSystemInformation: return "System Information"
-	case RoleManual:            return "Manual"
-	case RoleCamera:            return "Camera"
-	case RoleImageViewer:       return "Image Viewer"
-	case RoleMediaPlayer:       return "Media Player"
-	case RoleImageEditor:       return "Image Editor"
-	case RoleAudioEditor:       return "Audio Editor"
-	case RoleVideoEditor:       return "Video Editor"
-	case RoleClock:             return "Clock"
-	case RoleCalendar:          return "Calendar"
-	case RoleChecklist:         return "Checklist"
-	default:                    return "unknown"
-	}
-}
-
-// RunApplication is like Run, but runs an application.
-func RunApplication (application Application) error {
-	return Run(application.Init)
-}
-
-// 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) (Window, error) {
-	window, err := NewWindow(bounds)
-	if err != nil { return nil, err }
-	window.SetTitle(application.Describe().String())
-	return window, nil
-}

backend.go

@@ -11,12 +11,20 @@ import "git.tebibyte.media/tomo/tomo/canvas"
 type Backend interface {
 	// These methods create new objects. The backend must reject any object
 	// that was not made by it.
-	NewWindow       (image.Rectangle) (MainWindow, error)
 	NewBox          () Box
 	NewTextBox      () TextBox
 	NewCanvasBox    () CanvasBox
+	NewSurfaceBox   () (SurfaceBox, error)
 	NewContainerBox () ContainerBox
 
+	// NewWindow creates a normal MainWindow and returns it.
+	NewWindow (image.Rectangle) (MainWindow, error)
+
+	// NewPlainWindow creates an undecorated window that does not appear in
+	// window lists and returns it. This is intended for making things like
+	// panels, docks, etc.
+	NewPlainWindow (image.Rectangle) (MainWindow, error)
+
 	// NewTexture creates a new texture from an image. The backend must
 	// reject any texture that was not made by it.
 	NewTexture (image.Image) canvas.TextureCloser
@@ -52,11 +60,11 @@ func Register (priority int, factory Factory) {
 	})
 }
 
-// Initialize instantiates a backend. The first backend (sorted by priority)
+// initialize instantiates a backend. The first backend (sorted by priority)
 // that does not throw an error when initialized is used. If no backend could be
 // instantiated, this function returns an error. This function should be called
 // only once.
-func Initialize () (Backend, error) {
+func initialize () (Backend, error) {
 	backend, err := instantiate()
 	if err != nil { return nil, err }
 	return backend, err

canvas/canvas.go

@@ -8,9 +8,9 @@ import "image/color"
 
 // Cap represents a stroke cap type.
 type Cap int; const (
-	CapButt Cap = iota // Square cap that ends at the point
-	CapRound           // Round cap that surrounds the point
-	CapSquare          // square cap that surrounds the point
+	CapRound Cap = iota // Round cap that surrounds the point
+	CapSquare           // Square cap that surrounds the point
+	CapButt             // Square cap that ends at the point
 )
 
 // Joint represents a stroke joint type.
@@ -30,23 +30,38 @@ type StrokeAlign int; const (
 
 // Pen represents a drawing context that is linked to a canvas. Each canvas can
 // have multiple pens associated with it, each maintaining their own drawing
-// context.
+// state.
 type Pen interface {
-	// Rectangle draws a rectangle
+	// Rectangle draws a rectangle.
 	Rectangle (image.Rectangle)
 
-	// Path draws a path
+	// Path draws a path, which is a series of connected points.
 	Path (points ...image.Point)
 
-	Closed       (bool)        // if the path is closed
-	Cap          (Cap)         // line cap stype
-	Joint        (Joint)       // line joint style
-	StrokeWeight (int)         // how thick the stroke is
-	StrokeAlign  (StrokeAlign) // where the stroke is drawn
+	// StrokeWeight sets how thick the stroke is. The default value is zero.
+	StrokeWeight (int)
+	// SetClosed sets whether the path is a closed shape, or has an open
+	// side. This only applies if the stroke weight is greater than zero.
+	Closed (bool)
+	// Cap sets how the ends of the stroke look. This only applies if the
+	// stroke weight is greater than zero, and if the path is not closed.
+	// The default value is CapRound.
+	Cap (Cap)
+	// Joint sets how bend points in the stroke look. This only applies if
+	// the stroke weight is greater than zero. The default value is
+	// JointRound.
+	Joint (Joint)
+	// StrokeAlign sets where the stroke is drawn in relation to the path.
+	// This only applies if the stroke weight is greater than zero. The
+	// default value is StrokeAlignCenter.
+	StrokeAlign (StrokeAlign)
 
-	Stroke  (color.Color) // Sets the stroke to a solid color
-	Fill    (color.Color) // Sets the fill to a solid color
-	Texture (Texture)     // Overlaps a texture onto the fill color
+	// Stroke sets the stroke to a solid color.
+	Stroke (color.Color)
+	// Fill sets the fill to a solid color.
+	Fill (color.Color)
+	// Texture overlaps a texture onto the fill color.
+	Texture (Texture)
 }
 
 // Canvas is an image that supports drawing paths.
@@ -56,11 +71,13 @@ type Canvas interface {
 	// Pen returns a new pen for this canvas.
 	Pen () Pen
 
-	// Clip returns a new canvas that points to a specific area of this one.
-	Clip (image.Rectangle) Canvas
+	// SubCanvas returns a returns a Canvas representing the portion of this
+	// Canvas visible and drawable through a rectangle. The returned value
+	// shares pixels with the original Canvas.
+	SubCanvas (image.Rectangle) Canvas
 }
 
-// Drawer is an object that can draw to a canvas.
+// Drawer can draw to a canvas.
 type Drawer interface {
 	// Draw draws to the given canvas.
 	Draw (Canvas)

canvas/texture.go

@@ -7,9 +7,10 @@ import "image"
 type Texture interface {
 	image.Image
 
-	// Clip returns a smaller section of this texture, pointing to the same
-	// internal data.
-	Clip (image.Rectangle) Texture
+	// SubTexture returns a returns a Texture representing the portion of
+	// this Texture visible through a rectangle. The returned value shares
+	// pixels with the original Texture.
+	SubTexture (image.Rectangle) Texture
 }
 
 // TextureCloser is a texture that can be closed. Anything that receives a

icon.go

@@ -0,0 +1,393 @@
+package tomo
+
+import "git.tebibyte.media/tomo/tomo/data"
+import "git.tebibyte.media/tomo/tomo/canvas"
+
+// IconSize represents the size of an icon.
+type IconSize int; const (
+	IconSizeSmall IconSize = iota;
+	IconSizeMedium
+	IconSizeLarge
+)
+
+// String satisfies the fmt.Stringer interface.
+func (size IconSize) String () string {
+	switch size {
+	case IconSizeSmall:  return "small"
+	case IconSizeMedium: return "medium"
+	case IconSizeLarge:  return "large"
+	default:             return "unknown"
+	}
+}
+
+// Icon represents an icon ID.
+type Icon string
+
+// A list of standard icon IDs. This is roughly based off of the XDG Icon Naming
+// Specification (https://specifications.freedesktop.org/icon-naming-spec/icon-naming-spec-latest.html).
+const (
+	IconUnknown                      Icon = ""
+
+	// actions
+	IconAddressBookNew               Icon = "AddressBookNew"
+	IconApplicationExit              Icon = "ApplicationExit"
+	IconAppointmentNew               Icon = "AppointmentNew"
+	IconCallStart                    Icon = "CallStart"
+	IconCallStop                     Icon = "CallStop"
+	IconContactNew                   Icon = "ContactNew"
+	// actions: dialog
+	IconDialogOkay                   Icon = "DialogOkay"
+	IconDialogCancel                 Icon = "DialogCancel"
+	// actions: edit
+	IconEditClear                    Icon = "EditClear"
+	IconEditCopy                     Icon = "EditCopy"
+	IconEditCut                      Icon = "EditCut"
+	IconEditDelete                   Icon = "EditDelete"
+	IconEditFind                     Icon = "EditFind"
+	IconEditFindReplace              Icon = "EditFindReplace"
+	IconEditPaste                    Icon = "EditPaste"
+	IconEditRedo                     Icon = "EditRedo"
+	IconEditSelectAll                Icon = "EditSelectAll"
+	IconEditUndo                     Icon = "EditUndo"
+	// actions: file
+	IconFileNew                      Icon = "FileNew"
+	IconDirectoryNew                 Icon = "DirectoryNew"
+	IconFileOpen                     Icon = "FileOpen"
+	IconFileOpenRecent               Icon = "FileOpenRecent"
+	IconFilePageSetup                Icon = "FilePageSetup"
+	IconFilePrint                    Icon = "FilePrint"
+	IconFilePrintPreview             Icon = "FilePrintPreview"
+	IconFilePermissions              Icon = "FilePermissions"
+	IconFileProperties               Icon = "FileProperties"
+	IconFileRename                   Icon = "FileRename"
+	IconFileRevert                   Icon = "FileRevert"
+	IconFileSave                     Icon = "FileSave"
+	IconFileSaveAs                   Icon = "FileSaveAs"
+	IconFileSend                     Icon = "FileSend"
+	// actions: format
+	IconFormatIndentLess             Icon = "FormatIndentLess"
+	IconFormatIndentMore             Icon = "FormatIndentMore"
+	IconFormatAlignCenter            Icon = "FormatAlignCenter"
+	IconFormatAlignEven              Icon = "FormatAlignEven"
+	IconFormatAlignLeft              Icon = "FormatAlignLeft"
+	IconFormatAlignRight             Icon = "FormatAlignRight"
+	IconFormatTextDirectionLtr       Icon = "FormatTextDirectionLtr"
+	IconFormatTextDirectionRtl       Icon = "FormatTextDirectionRtl"
+	IconFormatTextBold               Icon = "FormatTextBold"
+	IconFormatTextItalic             Icon = "FormatTextItalic"
+	IconFormatTextUnderline          Icon = "FormatTextUnderline"
+	IconFormatTextStrikethrough      Icon = "FormatTextStrikethrough"
+	// actions: go
+	IconGoBottom                     Icon = "GoBottom"
+	IconGoDown                       Icon = "GoDown"
+	IconGoFirst                      Icon = "GoFirst"
+	IconGoHome                       Icon = "GoHome"
+	IconGoJump                       Icon = "GoJump"
+	IconGoLast                       Icon = "GoLast"
+	IconGoNext                       Icon = "GoNext"
+	IconGoPrevious                   Icon = "GoPrevious"
+	IconGoTop                        Icon = "GoTop"
+	IconGoUp                         Icon = "GoUp"
+	// actions: help
+	IconHelpAbout                    Icon = "HelpAbout"
+	IconHelpContents                 Icon = "HelpContents"
+	IconHelpFaq                      Icon = "HelpFaq"
+	// actions: insert
+	IconInsertImage                  Icon = "InsertImage"
+	IconInsertLink                   Icon = "InsertLink"
+	IconInsertObject                 Icon = "InsertObject"
+	IconInsertText                   Icon = "InsertText"
+	// actions: list
+	IconListAdd                      Icon = "ListAdd"
+	IconListRemove                   Icon = "ListRemove"
+	// actions: mail
+	IconMailForward                  Icon = "MailForward"
+	IconMailMarkImportant            Icon = "MailMarkImportant"
+	IconMailMarkJunk                 Icon = "MailMarkJunk"
+	IconMailMarkNotJunk              Icon = "MailMarkNotJunk"
+	IconMailMarkRead                 Icon = "MailMarkRead"
+	IconMailMarkUnread               Icon = "MailMarkUnread"
+	IconMailMessageNew               Icon = "MailMessageNew"
+	IconMailReplyAll                 Icon = "MailReplyAll"
+	IconMailReplySender              Icon = "MailReplySender"
+	IconMailSend                     Icon = "MailSend"
+	IconMailReceive                  Icon = "MailReceive"
+	// actions: media
+	IconMediaEject                   Icon = "MediaEject"
+	IconMediaPlaybackPause           Icon = "MediaPlaybackPause"
+	IconMediaPlaybackStart           Icon = "MediaPlaybackStart"
+	IconMediaPlaybackStop            Icon = "MediaPlaybackStop"
+	IconMediaRecord                  Icon = "MediaRecord"
+	IconMediaSeekBackward            Icon = "MediaSeekBackward"
+	IconMediaSeekForward             Icon = "MediaSeekForward"
+	IconMediaSkipBackward            Icon = "MediaSkipBackward"
+	IconMediaSkipForward             Icon = "MediaSkipForward"
+	// actions: object
+	IconObjectFlipHorizontal         Icon = "ObjectFlipHorizontal"
+	IconObjectFlipVertical           Icon = "ObjectFlipVertical"
+	IconObjectRotateLeft             Icon = "ObjectRotateLeft"
+	IconObjectRotateRight            Icon = "ObjectRotateRight"
+	// actions: process
+	IconProcessStop                  Icon = "ProcessStop"
+	// actions: system
+	IconSystemLockScreen             Icon = "SystemLockScreen"
+	IconSystemLogOut                 Icon = "SystemLogOut"
+	IconSystemRun                    Icon = "SystemRun"
+	IconSystemSearch                 Icon = "SystemSearch"
+	IconSystemReboot                 Icon = "SystemReboot"
+	IconSystemShutdown               Icon = "SystemShutdown"
+	// actions: tools
+	IconToolsCheckSpelling           Icon = "ToolsCheckSpelling"
+	// actions: value
+	IconValueIncrement               Icon = "ValueIncrement"
+	IconValueDecrement               Icon = "ValueDecrement"
+	IconValueReset                   Icon = "ValueReset"
+	// actions: view
+	IconViewFullscreen               Icon = "ViewFullscreen"
+	IconViewRefresh                  Icon = "ViewRefresh"
+	IconViewRestore                  Icon = "ViewRestore"
+	IconViewSortAscending            Icon = "ViewSortAscending"
+	IconViewSortDescending           Icon = "ViewSortDescending"
+	// actions: window
+	IconWindowClose                  Icon = "WindowClose"
+	IconWindowNew                    Icon = "WindowNew"
+	// actions: zoom
+	IconZoomFitBest                  Icon = "ZoomFitBest"
+	IconZoomIn                       Icon = "ZoomIn"
+	IconZoomOriginal                 Icon = "ZoomOriginal"
+	IconZoomOut                      Icon = "ZoomOut"
+	
+	// applications
+	// Keep these in sync with nasin.ApplicationRole!
+	IconApplication                  Icon = "Application" // generic
+	IconApplicationWebBrowser        Icon = "ApplicationWebBrowser"
+	IconApplicationMesssanger        Icon = "ApplicationMesssanger"
+	IconApplicationPhone             Icon = "ApplicationPhone"
+	IconApplicationMail              Icon = "ApplicationMail"
+	IconApplicationTerminalEmulator  Icon = "ApplicationTerminalEmulator"
+	IconApplicationFileBrowser       Icon = "ApplicationFileBrowser"
+	IconApplicationTextEditor        Icon = "ApplicationTextEditor"
+	IconApplicationDocumentViewer    Icon = "ApplicationDocumentViewer"
+	IconApplicationWordProcessor     Icon = "ApplicationWordProcessor"
+	IconApplicationSpreadsheet       Icon = "ApplicationSpreadsheet"
+	IconApplicationSlideshow         Icon = "ApplicationSlideshow"
+	IconApplicationCalculator        Icon = "ApplicationCalculator"
+	IconApplicationPreferences       Icon = "ApplicationPreferences"
+	IconApplicationProcessManager    Icon = "ApplicationProcessManager"
+	IconApplicationSystemInformation Icon = "ApplicationSystemInformation"
+	IconApplicationManual            Icon = "ApplicationManual"
+	IconApplicationCamera            Icon = "ApplicationCamera"
+	IconApplicationImageViewer       Icon = "ApplicationImageViewer"
+	IconApplicationMediaPlayer       Icon = "ApplicationMediaPlayer"
+	IconApplicationImageEditor       Icon = "ApplicationImageEditor"
+	IconApplicationAudioEditor       Icon = "ApplicationAudioEditor"
+	IconApplicationVideoEditor       Icon = "ApplicationVideoEditor"
+	IconApplicationClock             Icon = "ApplicationClock"
+	IconApplicationCalendar          Icon = "ApplicationCalendar"
+	IconApplicationChecklist         Icon = "ApplicationChecklist"
+
+	// categories: applications
+	IconApplications                 Icon = "Applications"
+	IconApplicationsAccessories      Icon = "ApplicationsAccessories"
+	IconApplicationsDevelopment      Icon = "ApplicationsDevelopment"
+	IconApplicationsEngineering      Icon = "ApplicationsEngineering"
+	IconApplicationsGames            Icon = "ApplicationsGames"
+	IconApplicationsGraphics         Icon = "ApplicationsGraphics"
+	IconApplicationsInternet         Icon = "ApplicationsInternet"
+	IconApplicationsMultimedia       Icon = "ApplicationsMultimedia"
+	IconApplicationsOffice           Icon = "ApplicationsOffice"
+	IconApplicationsScience          Icon = "ApplicationsScience"
+	IconApplicationsSystem           Icon = "ApplicationsSystem"
+	IconApplicationsUtilities        Icon = "ApplicationsUtilities"
+	// categories: preferences
+	IconPreferences                  Icon = "Preferences"
+	IconPreferencesDesktop           Icon = "PreferencesDesktop"
+	IconPreferencesPeripherals       Icon = "PreferencesPeripherals"
+	IconPreferencesPersonal          Icon = "PreferencesPersonal"
+	IconPreferencesSystem            Icon = "PreferencesSystem"
+	IconPreferencesNetwork           Icon = "PreferencesNetwork"
+
+	// devices
+	IconDevice                       Icon = "Device"
+	IconDeviceCamera                 Icon = "DeviceCamera"
+	IconDeviceWebCamera              Icon = "DeviceWebCamera"
+	IconDeviceComputer               Icon = "DeviceComputer"
+	IconDevicePda                    Icon = "DevicePda"
+	IconDevicePhone                  Icon = "DevicePhone"
+	IconDevicePrinter                Icon = "DevicePrinter"
+	IconDeviceScanner                Icon = "DeviceScanner"
+	IconDeviceMultimediaPlayer       Icon = "DeviceMultimediaPlayer"
+	IconDeviceVideoDisplay           Icon = "DeviceVideoDisplay"
+	IconDeviceAudioInput             Icon = "DeviceAudioInput"
+	IconDeviceAudioOutput            Icon = "DeviceAudioOutput"
+	// devices: hardware
+	IconHardware                     Icon = "Hardware"
+	IconHardwareCPU                  Icon = "HardwareCPU"
+	IconHardwareGPU                  Icon = "HardwareGPU"
+	IconHardwareRAM                  Icon = "HardwareRAM"
+	IconHardwareSoundCard            Icon = "HardwareSoundCard"
+	IconHardwareNetworkAdapter       Icon = "HardwareNetworkAdapter"
+	// devices: power
+	IconPowerBattery                 Icon = "PowerBattery"
+	// devices: storage
+	IconStorageHardDisk              Icon = "StorageHardDisk"
+	IconStorageFloppyDisk            Icon = "StorageFloppyDisk"
+	IconStorageSolidState            Icon = "StorageSolidState"
+	IconStorageOptical               Icon = "StorageOptical"
+	IconStorageFlashStick            Icon = "StorageFlashStick"
+	IconStorageFlashCard             Icon = "StorageFlashCard"
+	IconStorageMagneticTape          Icon = "StorageMagneticTape"
+	// devices: input
+	IconInputGaming                  Icon = "InputGaming"
+	IconInputKeyboard                Icon = "InputKeyboard"
+	IconInputMouse                   Icon = "InputMouse"
+	IconInputTablet                  Icon = "InputTablet"
+	// devices: network
+	IconNetworkWired                 Icon = "NetworkWired"
+	IconNetworkWireless              Icon = "NetworkWireless"
+	IconNetworkCellular              Icon = "NetworkCellular"
+	IconNetworkLocal                 Icon = "NetworkLocal"
+	IconNetworkInternet              Icon = "NetworkInternet"
+	IconNetworkVPN                   Icon = "NetworkVPN"
+	IconNetworkServer                Icon = "NetworkServer"
+	IconNetworkWorkgroup             Icon = "NetworkWorkgroup"
+
+	// emblems
+	IconEmblemDefault                Icon = "EmblemDefault"
+	IconEmblemEncrypted              Icon = "EmblemEncrypted"
+	IconEmblemFavorite               Icon = "EmblemFavorite"
+	IconEmblemImportant              Icon = "EmblemImportant"
+	IconEmblemReadOnly               Icon = "EmblemReadOnly"
+	IconEmblemShared                 Icon = "EmblemShared"
+	IconEmblemSymbolicLink           Icon = "EmblemSymbolicLink"
+	IconEmblemSynchronized           Icon = "EmblemSynchronized"
+	IconEmblemSystem                 Icon = "EmblemSystem"
+	IconEmblemUnreadable             Icon = "EmblemUnreadable"
+
+	// places
+	IconPlaceDirectory               Icon = "PlaceDirectory"
+	IconPlaceRemote                  Icon = "PlaceRemote"
+	IconPlaceHome                    Icon = "PlaceHome"
+	IconPlaceDownloads               Icon = "PlaceDownloads"
+	IconPlaceDesktop                 Icon = "PlaceDesktop"
+	IconPlacePhotos                  Icon = "PlacePhotos"
+	IconPlaceBooks                   Icon = "PlaceBooks"
+	IconPlaceBookmarks               Icon = "PlaceBookmarks"
+	IconPlaceTrash                   Icon = "PlaceTrash"
+	IconPlaceDocuments               Icon = "PlaceDocuments"
+	IconPlaceRepositories            Icon = "PlaceRepositories"
+	IconPlaceMusic                   Icon = "PlaceMusic"
+	IconPlaceArchives                Icon = "PlaceArchives"
+	IconPlaceFonts                   Icon = "PlaceFonts"
+	IconPlaceBinaries                Icon = "PlaceBinaries"
+	IconPlaceVideos                  Icon = "PlaceVideos"
+	IconPlace3DObjects               Icon = "Place3DObjects"
+	IconPlaceHistory                 Icon = "PlaceHistory"
+	IconPlacePreferences             Icon = "PlacePreferences"
+
+	// status: checkbox
+	IconCheckboxChecked              Icon = "CheckboxChecked"
+	IconCheckboxUnchecked            Icon = "CheckboxUnchecked"
+	// status: appointments
+	IconAppointmentMissed            Icon = "AppointmentMissed"
+	IconAppointmentSoon              Icon = "AppointmentSoon"
+	// status: dialogs
+	IconDialogError                  Icon = "DialogError"
+	IconDialogInformation            Icon = "DialogInformation"
+	IconDialogPassword               Icon = "DialogPassword"
+	IconDialogQuestion               Icon = "DialogQuestion"
+	IconDialogWarning                Icon = "DialogWarning"
+	// status: directories
+	IconDirectoryDragAccept          Icon = "DirectoryDragAccept"
+	IconDirectoryFull                Icon = "DirectoryFull"
+	IconDirectoryOpen                Icon = "DirectoryOpen"
+	IconDirectoryVisiting            Icon = "DirectoryVisiting"
+	// status: trash
+	IconTrashFull                    Icon = "TrashFull"
+	// status: resource
+	IconResourceLoading              Icon = "ResourceLoading"
+	IconResourceMissing              Icon = "ResourceMissing"
+	// status: mail
+	IconMailAttachment               Icon = "MailAttachment"
+	IconMailUnread                   Icon = "MailUnread"
+	IconMailReplied                  Icon = "MailReplied"
+	IconMailSigned                   Icon = "MailSigned"
+	IconMailSignedVerified           Icon = "MailSignedVerified"
+	// status: network
+	IconCellularSignal0              Icon = "CellularSignal0"
+	IconCellularSignal1              Icon = "CellularSignal1"
+	IconCellularSignal2              Icon = "CellularSignal2"
+	IconCellularSignal3              Icon = "CellularSignal3"
+	IconWirelessSignal0              Icon = "WirelessSignal0"
+	IconWirelessSignal1              Icon = "WirelessSignal1"
+	IconWirelessSignal2              Icon = "WirelessSignal2"
+	IconWirelessSignal3              Icon = "WirelessSignal3"
+	IconNetworkError                 Icon = "NetworkError"
+	IconNetworkIdle                  Icon = "NetworkIdle"
+	IconNetworkOffline               Icon = "NetworkOffline"
+	IconNetworkReceive               Icon = "NetworkReceive"
+	IconNetworkTransmit              Icon = "NetworkTransmit"
+	IconNetworkTransmitReceive       Icon = "NetworkTransmitReceive"
+	// status: print
+	IconPrintError                   Icon = "PrintError"
+	IconPrintPrinting                Icon = "PrintPrinting"
+	// status: security
+	IconSecurityHigh                 Icon = "SecurityHigh"
+	IconSecurityMedium               Icon = "SecurityMedium"
+	IconSecurityLow                  Icon = "SecurityLow"
+	// status: software
+	IconSoftwareUpdateAvailable      Icon = "SoftwareUpdateAvailable"
+	IconSoftwareUpdateUrgent         Icon = "SoftwareUpdateUrgent"
+	IconSoftwareInstalling           Icon = "SoftwareInstalling"
+	// status: sync
+	IconSyncError                    Icon = "SyncError"
+	IconSyncSynchronizing            Icon = "SyncSynchronizing"
+	// status: tasks
+	IconTaskDue                      Icon = "TaskDue"
+	IconTaskPastDue                  Icon = "TaskPastDue"
+	// status: users
+	IconUserAvailable                Icon = "UserAvailable"
+	IconUserAway                     Icon = "UserAway"
+	IconUserIdle                     Icon = "UserIdle"
+	IconUserOffline                  Icon = "UserOffline"
+	// status: power
+	IconBattery0                     Icon = "Battery0"
+	IconBattery1                     Icon = "Battery1"
+	IconBattery2                     Icon = "Battery2"
+	IconBattery3                     Icon = "Battery3"
+	IconBrightness0                  Icon = "Brightness0"
+	IconBrightness1                  Icon = "Brightness1"
+	IconBrightness2                  Icon = "Brightness2"
+	IconBrightness3                  Icon = "Brightness3"
+	// status: media
+	IconVolume0                      Icon = "Volume0"
+	IconVolume1                      Icon = "Volume1"
+	IconVolume2                      Icon = "Volume2"
+	IconVolume3                      Icon = "Volume3"
+	IconPlaylistRepeat               Icon = "PlaylistRepeat"
+	IconPlaylistShuffle              Icon = "PlaylistShuffle"
+	// status: weather
+	IconWeatherClear                 Icon = "WeatherClear"
+	IconWeatherClearNight            Icon = "WeatherClearNight"
+	IconWeatherFewClouds             Icon = "WeatherFewClouds"
+	IconWeatherFewCloudsNight        Icon = "WeatherFewCloudsNight"
+	IconWeatherFog                   Icon = "WeatherFog"
+	IconWeatherOvercast              Icon = "WeatherOvercast"
+	IconWeatherSevereAlert           Icon = "WeatherSevereAlert"
+	IconWeatherShowers               Icon = "WeatherShowers"
+	IconWeatherShowersScattered      Icon = "WeatherShowersScattered"
+	IconWeatherSnow                  Icon = "WeatherSnow"
+	IconWeatherStorm                 Icon = "WeatherStorm"
+)
+
+// Texture returns a texture of the corresponding icon ID.
+func (id Icon) Texture (size IconSize) canvas.Texture {
+	if theme == nil { return nil }
+	return theme.Icon(id, size)
+}
+
+// MimeIcon returns an icon corresponding to a MIME type.
+func MimeIcon (mime data.Mime, size IconSize) canvas.Texture {
+	if theme == nil { return nil }
+	return theme.MimeIcon(mime, size)
+}

object.go

@@ -101,24 +101,41 @@ type Align int; const (
 	AlignEven               // similar to justified text
 )
 
-// Object is any obscreen object. Each object must be linked to a box, even if
-// it is that box.
+// Object is any onscreen object that is linked to a box (or is that box).
+// Unlike the Box interface and associated interfaces, Object implementations
+// may originate from anywhere.
 type Object interface {
 	GetBox () Box
 }
 
-// Box is a basic styled box.
+// ContentObject is an object that has some kind of content.
+type ContentObject interface {
+	Object
+
+	// ContentBounds returns the bounds of the inner content of the Box
+	// relative to the Box's InnerBounds.
+	ContentBounds () image.Rectangle
+	// ScrollTo shifts the origin of the Box's content to the origin of the
+	// Box's InnerBounds, offset by the given point.
+	ScrollTo (image.Point)
+	// OnContentBoundsChange specifies a function to be called when the
+	// Box's ContentBounds or InnerBounds changes.
+	OnContentBoundsChange (func ()) event.Cookie
+}
+
+// Box is a basic styled box. Implementations of Box, as well as any interface
+// that embed Box, may only originate from a Backend.
 type Box interface {
 	Object
 
 	// Window returns the Window this Box is a part of.
-	Window         () Window
+	Window () Window
 	// Bounds returns the outer bounding rectangle of the Box relative to
 	// the Window.
-	Bounds         () image.Rectangle
+	Bounds () image.Rectangle
 	// InnerBounds returns the inner bounding rectangle of the box. It is
 	// the value of Bounds inset by the Box's border and padding.
-	InnerBounds    () image.Rectangle
+	InnerBounds () image.Rectangle
 	// MinimumSize returns the minimum width and height this Box's bounds
 	// can be set to. This will return the value of whichever of these is
 	// greater:
@@ -126,30 +143,36 @@ type Box interface {
 	//   - The size taken up by the Box's border and padding. If there is
 	//     internal content that does not overflow, the size of that is also
 	//     taken into account here.
-	MinimumSize    () image.Point
+	MinimumSize () image.Point
 	// SetBounds sets the bounding rectangle of this Box relative to the
 	// Window.
-	SetBounds      (image.Rectangle)
+	SetBounds (image.Rectangle)
 	// SetColor sets the background color of this Box.
-	SetColor       (color.Color)
-	// SetTexture sets a repeating background texture. If the texture is
+	SetColor (color.Color)
+	// SetTextureTile sets a repeating background texture. If the texture is
 	// transparent, it will be overlayed atop the color specified by
-	// SetColor().
-	SetTexture     (canvas.Texture)
+	// SetColor(). This will remove any previous texture set by this method
+	// or another method.
+	SetTextureTile (canvas.Texture)
+	// SetTextureCenter sets a centered background texture. If the texture
+	// is transparent, it will be overlayed atop the color specified by
+	// SetColor(). This will remove any previous texture set by this method
+	// or another method.
+	SetTextureCenter (canvas.Texture)
 	// SetBorder sets the Border(s) of the box. The first Border will be the
 	// most outset, and the last Border will be the most inset.
-	SetBorder      (...Border)
+	SetBorder (...Border)
 	// SetMinimumSize sets the minimum width and height of the box, as
 	// described in MinimumSize.
 	SetMinimumSize (image.Point)
 	// SetPadding sets the padding between the Box's innermost Border and
 	// its content.
-	SetPadding     (Inset)
+	SetPadding (Inset)
 
 	// SetDNDData sets the data that will be picked up if this Box is
 	// dragged. If this is nil (which is the default), this Box will not be
 	// picked up.
-	SetDNDData   (data.Data)
+	SetDNDData (data.Data)
 	// SetDNDAccept sets the type of data that can be dropped onto this Box.
 	// If this is nil (which is the default), this Box will reject all
 	// drops.
@@ -157,16 +180,16 @@ type Box interface {
 	// SetFocused sets whether or not this Box has keyboard focus. If set to
 	// true, this method will steal focus away from whichever Object
 	// currently has focus.
-	SetFocused   (bool)
+	SetFocused (bool)
 	// SetFocusable sets whether or not this Box can receive keyboard focus.
 	// If set to false and the Box is already focused. the focus is removed.
 	SetFocusable (bool)
 
 	// Focused returns whether or not this Box has keyboard focus.
-	Focused       () bool
+	Focused () bool
 	// Modifiers returns which modifier keys on the keyboard are currently
 	// being held down.
-	Modifiers     () input.Modifiers
+	Modifiers () input.Modifiers
 	// MousePosition returns the position of the mouse pointer relative to
 	// the Window.
 	MousePosition () image.Point
@@ -195,32 +218,54 @@ type CanvasBox interface {
 	Box
 
 	// SetDrawer sets the Drawer that will be called upon to draw the Box's
-	// content when it is invalidated.
-	SetDrawer  (canvas.Drawer)
+	// content when it is invalidated. The Canvas passed to the drawer will
+	// have these properties:
+	//   - It will have the same origin (0, 0) as the window which contains
+	//     the CanvasBox
+	//   - The Canvas bounds will describe the portion of the CanvasBox
+	//     visible on screen
+	SetDrawer (canvas.Drawer)
 
 	// Invalidate causes the Box's area to be redrawn at the end of the
 	// event cycle, even if it wouldn't be otherwise.
 	Invalidate ()
 }
 
-// ContentBox is an abstract box that has some kind of content. Its only purpose
-// is to be embedded into TextBox and ContainerBox.
+// SurfaceBox is a box that can be drawn to via a hardware accelerated (or
+// platform-specific) graphics context.
+type SurfaceBox interface {
+	Box
+
+	// Surface returns the underlying graphics context. The result must be
+	// asserted to the expected type or passed through a type switch before
+	// use. The exact type returned here depends on the backend being used,
+	// and it is up to the application author to ensure that the application
+	// and backend agree on it. Applications should fail gracefully if the
+	// expected type was not found.
+	Surface () any
+	
+	// Invalidate causes the Box's area to be redrawn at the end of the
+	// event cycle, even if it wouldn't be otherwise.
+	Invalidate ()
+}
+
+// ContentBox is a box that has some kind of content.
 type ContentBox interface {
 	Box
 
 	// SetOverflow sets whether or not the Box's content overflows
 	// horizontally and vertically. Overflowing content is clipped to the
 	// bounds of the Box inset by all Borders (but not padding).
-	SetOverflow           (horizontal, vertical bool)
+	SetOverflow (horizontal, vertical bool)
 	// SetAlign sets how the Box's content is distributed horizontally and
 	// vertically.
-	SetAlign              (x, y Align)
+	SetAlign (x, y Align)
 	// ContentBounds returns the bounds of the inner content of the Box
-	// relative to the window.
-	ContentBounds         () image.Rectangle
+	// relative to the Box's InnerBounds.
+	ContentBounds () image.Rectangle
 	// ScrollTo shifts the origin of the Box's content to the origin of the
 	// Box's InnerBounds, offset by the given point.
-	ScrollTo              (image.Point)
+	ScrollTo (image.Point)
 	// OnContentBoundsChange specifies a function to be called when the
 	// Box's ContentBounds or InnerBounds changes.
 	OnContentBoundsChange (func ()) event.Cookie
@@ -231,26 +276,26 @@ type TextBox interface {
 	ContentBox
 
 	// SetText sets the text content of the Box.
-	SetText       (string)
+	SetText (string)
 	// SetTextColor sets the text color.
-	SetTextColor  (color.Color)
+	SetTextColor (color.Color)
 	// SetFace sets the font face text is rendered in.
-	SetFace       (font.Face)
+	SetFace (font.Face)
 	// SetWrap sets whether or not the text wraps.
-	SetWrap       (bool)
+	SetWrap (bool)
 
 	// SetSelectable sets whether or not the text content can be
 	// highlighted/selected.
 	SetSelectable (bool)
 	// SetDotColor sets the highlight color of selected text.
-	SetDotColor   (color.Color)
+	SetDotColor (color.Color)
 	// Select sets the text cursor or selection.
-	Select        (text.Dot)
+	Select (text.Dot)
 	// Dot returns the text cursor or selection.
-	Dot           () text.Dot
+	Dot () text.Dot
 	// OnDotChange specifies a function to be called when the text cursor or
 	// selection changes.
-	OnDotChange   (func ()) event.Cookie
+	OnDotChange (func ()) event.Cookie
 }
 
 // ContentBox is a box that can contain child Objects. It arranges them
@@ -258,30 +303,35 @@ type TextBox interface {
 type ContainerBox interface {
 	ContentBox
 
-	// SetPropagateEvents specifies whether or not child Objects will
-	// receive user input events. It is true by default. If it is false, all
-	// user input that would otherwise be directed to a child Box is
-	// directed to this Box.
-	SetPropagateEvents (bool)
 	// SetGap sets the gap between child Objects.
-	SetGap             (image.Point)
-	// Add appends a child Object.
-	Add                (Object)
-	// Delete removes a child Object, if it is a child of this Box.
-	Delete             (Object)
+	SetGap (image.Point)
+	// Add appends a child Object. If the object is already a child of
+	// another object, it will be removed from that object first.
+	Add (Object)
+	// Remove removes a child Object, if it is a child of this Box.
+	Remove (Object)
 	// Insert inserts a child Object before a specified Object. If the
 	// before Object is nil or is not contained within this Box, the
 	// inserted Object is appended.
-	Insert             (child Object, before Object)
+	Insert (child Object, before Object)
 	// Clear removes all child Objects.
-	Clear              ()
-	// Length returns the amount of child objects.
-	Length             () int
+	Clear ()
+	// Length returns the amount of child Objects.
+	Length () int
 	// At returns the child Object at the specified index.
-	At                 (int) Object
+	At (int) Object
 	// SetLayout sets the layout of this Box. Child Objects will be
 	// positioned according to it.
-	SetLayout          (Layout)
+	SetLayout (Layout)
+
+	// These methods control whether certain user input events get
+	// propagated to child Objects. If set to true, the relevant events will
+	// be sent to this container. If set to false (which is the default),
+	// the events will be sent to the appropriate child Object.
+	CaptureDND      (bool)
+	CaptureMouse    (bool)
+	CaptureScroll   (bool)
+	CaptureKeyboard (bool)
 }
 
 // LayoutHints are passed to a layout to tell it how to arrange child boxes.
@@ -289,14 +339,14 @@ type LayoutHints struct {
 	// Bounds is the bounding rectangle that children should be placed
 	// within. Any padding values are already applied.
 	Bounds image.Rectangle
-	// OverflowX and OverflowY control wether child Boxes may be positioned
+	// OverflowX and OverflowY control whether child Boxes may be positioned
 	// outside of Bounds.
 	OverflowX bool
 	OverflowY bool
 	// AlignX and AlignY control how child Boxes are aligned horizontally
 	// and vertically. The effect of this may vary depending on the Layout.
-	AlignX    Align
-	AlignY    Align
+	AlignX Align
+	AlignY Align
 	// Gap controls the amount of horizontal and vertical spacing in-between
 	// child Boxes.
 	Gap image.Point
@@ -308,43 +358,44 @@ type Layout interface {
 	// LayoutHints.Bounds needed to properly lay out all child Boxes.
 	MinimumSize (LayoutHints, []Box) image.Point
 	// Arrange arranges child boxes according to the given LayoutHints.
-	Arrange     (LayoutHints, []Box)
+	Arrange (LayoutHints, []Box)
 }
 
 // Window is an operating system window. It can contain one object.
 type Window interface {
 	// SetRoot sets the root child of the window. There can only be one at
 	// a time, and setting it will remove the current child if there is one.
-	SetRoot  (Object)
+	SetRoot (Object)
 	// SetTitle sets the title of the window.
 	SetTitle (string)
 	// SetIcon sets the icon of the window. When multiple icon sizes are
 	// provided, the best fitting one is chosen for display.
-	SetIcon  (... image.Image)
+	SetIcon (... image.Image)
 	// Widget returns a window representing a smaller iconified form of this
 	// window. How exactly this window is used depends on the platform.
 	// Subsequent calls to this method on the same window will return the
 	// same window object.
-	Widget   () (Window, error)
+	Widget () (Window, error)
 	// NewMenu creates a new menu window. This window is undecorated and
 	// will close once the user clicks outside of it.
-	NewMenu  (image.Rectangle) (Window, error)
+	NewMenu (image.Rectangle) (Window, error)
 	// NewModal creates a new modal window that blocks all input to this
 	// window until it is closed.
 	NewModal (image.Rectangle) (Window, error)
 	// Copy copies data to the clipboard.
-	Copy     (data.Data)
+	Copy (data.Data)
 	// Paste reads data from the clipboard. When the data is available or an
 	// error has occurred, the provided function will be called.
-	Paste    (callback func (data.Data, error), accept ...data.Mime)
-	// Show shows the window.
-	Show     ()
-	// Hide hides the window.
-	Hide     ()
+	Paste (callback func (data.Data, error), accept ...data.Mime)
+	// SetVisible sets whether or not this window is visible. Windows are
+	// invisible by default.
+	SetVisible (bool)
+	// Visible returns whether or not this window is visible.
+	Visible () bool
 	// Close closes the window.
-	Close    ()
+	Close ()
 	// OnClose specifies a function to be called when the window is closed.
-	OnClose  (func ()) event.Cookie
+	OnClose (func ()) event.Cookie
 }
 
 // MainWindow is a top-level operating system window.

path.go

@@ -1,187 +0,0 @@
-package tomo
-
-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
-}
-
-// FileWriter is a writable version of fs.File. 
-type FileWriter interface {
-	interface { fs.File; io.Writer }
-}
-
-// ApplicationUserDataFS returns an FS that an application can use to store user
-// data files.
-func ApplicationUserDataFS (app ApplicationDescription) (*FS, error) {
-	return appFs(userDataDir, app)
-}
-
-// ApplicationUserConfigFS returns an FS that an application can use to store
-// user configuration files.
-func ApplicationUserConfigFS (app ApplicationDescription) (*FS, error) {
-	configDir, err := os.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 := os.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
-	appname := app.String()
-	appname = strings.ReplaceAll(appname, "/", "-")
-	appname = strings.ReplaceAll(appname, "\\", "-")
-
-	path := filepath.Join(root, appname)
-	
-	// ensure the directory actually exists
-	err := os.MkdirAll(path, 755)
-	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)
-}

plugin.go

@@ -1,55 +0,0 @@
-package tomo
-
-import "os"
-import "plugin"
-import "path/filepath"
-
-var pluginPaths []string
-
-func loadPlugins () {
-	for _, dir := range pluginPaths {
-		if dir != "" {
-			loadPluginsFrom(dir)
-		}
-	}
-}
-
-func loadPluginsFrom (dir string) {
-	entries, err := os.ReadDir(dir)
-	// its no big deal if one of the dirs doesn't exist
-	if err != nil { return }
-
-	for _, entry := range entries {
-		if entry.IsDir() { continue }
-		if filepath.Ext(entry.Name()) != ".so" { continue }
-		pluginPath := filepath.Join(dir, entry.Name())
-		loadPlugin(pluginPath)
-	}
-}
-
-func loadPlugin (path string) {
-	die := func (reason string) {
-		println("tomo: could not load plugin at", path + ":", reason)
-	}
-
-	plugin, err := plugin.Open(path)
-	if err != nil {
-		die(err.Error())
-		return
-	}
-
-	// check for and obtain basic plugin functions
-	name, ok := extract[func () string](plugin, "Name")
-	if !ok { die("does not implement Name() string"); return }
-	_, ok = extract[func () string](plugin, "Description")
-	if !ok { die("does not implement Description() string"); return }
-
-	println("tomo: loaded plugin", name())
-}
-
-func extract[T any] (plugin *plugin.Plugin, name string) (value T, ok bool) {
-	symbol, err := plugin.Lookup(name)
-	if err != nil { return }
-	value, ok = symbol.(T)
-	return
-}

theme.go

@@ -1,7 +1,6 @@
-package theme
+package tomo
 
 import "fmt"
-import "git.tebibyte.media/tomo/tomo"
 import "git.tebibyte.media/tomo/tomo/data"
 import "git.tebibyte.media/tomo/tomo/event"
 import "git.tebibyte.media/tomo/tomo/canvas"
@@ -61,11 +60,11 @@ func (c Color) String () string {
 
 // RGBA satisfies the color.Color interface.
 func (id Color) RGBA () (r, g, b, a uint32) {
-	if current == nil { return }
-	return current.RGBA(id)
+	if theme == nil { return }
+	return theme.RGBA(id)
 }
 
-// Theme is an object that can apply a visual style to different objects.
+// Theme can apply a visual style to different objects.
 type Theme interface {
 	// A word on textures:
 	//
@@ -81,32 +80,32 @@ type Theme interface {
 	// Apply applies the theme to the given object, according to the given
 	// role. This may register event listeners with the given object;
 	// closing the returned cookie must remove them.
-	Apply (tomo.Object, Role) event.Cookie
+	Apply (Object, Role) event.Cookie
 
 	// RGBA returns the RGBA values of the corresponding color ID.
 	RGBA (Color) (r, g, b, a uint32)
 
-	// Icon returns a texture of the corresponding icon ID.
+	// Icon returns a texture of the corresponding icon ID. If there is no
+	// suitable option, it should return nil.
 	Icon (Icon, IconSize) canvas.Texture
 
-	// MimeIcon returns an icon corresponding to a MIME type.
+	// MimeIcon returns a texture of an icon corresponding to a MIME type.
+	// If there is no suitable specific option, it should return a more
+	// generic icon or a plain file icon.
 	MimeIcon (data.Mime, IconSize) canvas.Texture
-
-	// ApplicationIcon returns an icon corresponding to an application.
-	ApplicationIcon (ApplicationIcon, IconSize) canvas.Texture
 }
 
-var current Theme
+var theme Theme
 
 // SetTheme sets the theme.
-func SetTheme (theme Theme) {
-	current = theme
+func SetTheme (them Theme) {
+	theme = them
 }
 
 // Apply applies the current theme to the given object, according to the given
 // role. This may register event listeners with the given object; closing the
 // returned cookie will remove them.
-func Apply (object tomo.Object, role Role) event.Cookie {
-	if current == nil { return event.NoCookie { } }
-	return current.Apply(object, role)
+func Apply (object Object, role Role) event.Cookie {
+	if theme == nil { return event.NoCookie { } }
+	return theme.Apply(object, role)
 }

theme/icon.go

@@ -1,440 +0,0 @@
-package theme
-
-import "git.tebibyte.media/tomo/tomo"
-import "git.tebibyte.media/tomo/tomo/data"
-import "git.tebibyte.media/tomo/tomo/canvas"
-
-// IconSize represents the size of an icon.
-type IconSize int; const (
-	IconSizeSmall IconSize = iota;
-	IconSizeMedium
-	IconSizeLarge
-)
-
-// String satisfies the fmt.Stringer interface.
-func (size IconSize) String () string {
-	switch size {
-	case IconSizeSmall:  return "small"
-	case IconSizeMedium: return "medium"
-	case IconSizeLarge:  return "large"
-	default:             return "unknown"
-	}
-}
-
-// TODO: the Icon type, along with its String method, needs to be codegen'd.
-
-// Icon represents an icon ID.
-type Icon int; const (
-	// --- Objects --- //
-
-	// files
-	IconFile Icon = iota
-	IconDirectory
-	IconDirectoryFull
-
-	// places
-	IconDownloads
-	IconPhotos
-	IconBooks
-	IconDocuments
-	IconRepositories
-	IconMusic
-	IconArchives
-	IconFonts
-	IconBinaries
-	IconVideos
-	Icon3DObjects
-	IconHistory
-	IconPreferences
-
-	// storage
-	IconStorage // generic
-	IconMagneticTape
-	IconFloppyDisk
-	IconHardDisk
-	IconSolidStateDrive
-	IconFlashDrive
-	IconMemoryCard
-	IconROMDisk
-	IconRAMDisk
-	IconCD
-	IconDVD
-
-	// network
-	IconNetwork // generic
-	IconLocalNetwork
-	IconInternet
-	IconEthernet
-	IconWireless
-	IconCell
-	IconBluetooth
-	IconRadio
-
-	// devices
-	IconDevice // generic
-	IconRouter
-	IconServer
-	IconDesktop
-	IconLaptop
-	IconTablet
-	IconPhone
-	IconWatch
-	IconCamera
-
-	// peripherals
-	IconPeripheral // generic
-	IconKeyboard
-	IconMouse
-	IconMonitor
-	IconWebcam
-	IconMicrophone
-	IconSpeaker
-	IconPenTablet
-	IconTrackpad
-	IconController
-
-	// i/o
-	IconPort // generic
-	IconEthernetPort
-	IconUSBPort
-	IconParallelPort
-	IconSerialPort
-	IconPS2Port
-	IconDisplayConnector
-	IconCGAPort
-	IconVGAPort
-	IconHDMIPort
-	IconDisplayPort
-	IconInfrared
-
-	// --- Actions --- //
-
-	// files
-	IconOpen
-	IconOpenIn
-	IconSave
-	IconSaveAs
-	IconPrint
-	IconNew
-	IconNewDirectory
-	IconDelete
-	IconRename
-	IconGetInformation
-	IconChangePermissions
-	IconRevert
-
-	// list management
-	IconAdd
-	IconRemove
-	IconAddBookmark
-	IconRemoveBookmark
-	IconAddFavorite
-	IconRemoveFavorite
-
-	// media
-	IconPlay
-	IconPause
-	IconStop
-	IconFastForward
-	IconRewind
-	IconToBeginning
-	IconToEnd
-	IconRecord
-	IconVolumeUp
-	IconVolumeDown
-	IconMute
-
-	// editing
-	IconUndo
-	IconRedo
-	IconCut
-	IconCopy
-	IconPaste
-	IconFind
-	IconReplace
-	IconSelectAll
-	IconSelectNone
-	IconIncrement
-	IconDecrement
-
-	// window management
-	IconClose
-	IconQuit
-	IconIconify
-	IconShade
-	IconMaximize
-	IconFullScreen
-	IconRestore
-
-	// view controls
-	IconExpand
-	IconContract
-	IconBack
-	IconForward
-	IconUp
-	IconDown
-	IconReload
-	IconZoomIn
-	IconZoomOut
-	IconZoomReset
-	IconMove
-	IconResize
-	IconGoTo
-
-	// tools
-	IconTransform
-	IconTranslate
-	IconRotate
-	IconScale
-	IconWarp
-	IconCornerPin
-	IconSelectRectangle
-	IconSelectEllipse
-	IconSelectLasso
-	IconSelectGeometric
-	IconSelectAuto
-	IconCrop
-	IconFill
-	IconGradient
-	IconPencil
-	IconBrush
-	IconEraser
-	IconText
-	IconEyedropper
-
-	// --- Status --- //
-
-	// dialogs
-	IconInformation
-	IconQuestion
-	IconWarning
-	IconError
-	IconCancel
-	IconOkay
-
-	// network
-	IconCellSignal0
-	IconCellSignal1
-	IconCellSignal2
-	IconCellSignal3
-	IconWirelessSignal0
-	IconWirelessSignal1
-	IconWirelessSignal2
-	IconWirelessSignal3
-
-	// power
-	IconBattery0
-	IconBattery1
-	IconBattery2
-	IconBattery3
-	IconBrightness0
-	IconBrightness1
-	IconBrightness2
-	IconBrightness3
-
-	// media
-	IconVolume0
-	IconVolume1
-	IconVolume2
-	IconVolume3
-)
-
-// String satisfies the fmt.Stringer interface.
-func (id Icon) String () string {
-	switch id {
-	case IconFile: return "File"
-	case IconDirectory: return "Directory"
-	case IconDirectoryFull: return "DirectoryFull"
-	case IconDownloads: return "Downloads"
-	case IconPhotos: return "Photos"
-	case IconBooks: return "Books"
-	case IconDocuments: return "Documents"
-	case IconRepositories: return "Repositories"
-	case IconMusic: return "Music"
-	case IconArchives: return "Archives"
-	case IconFonts: return "Fonts"
-	case IconBinaries: return "Binaries"
-	case IconVideos: return "Videos"
-	case Icon3DObjects: return "3DObjects"
-	case IconHistory: return "History"
-	case IconPreferences: return "Preferences"
-	case IconStorage: return "Storage"
-	case IconMagneticTape: return "MagneticTape"
-	case IconFloppyDisk: return "FloppyDisk"
-	case IconHardDisk: return "HardDisk"
-	case IconSolidStateDrive: return "SolidStateDrive"
-	case IconFlashDrive: return "FlashDrive"
-	case IconMemoryCard: return "MemoryCard"
-	case IconROMDisk: return "ROMDisk"
-	case IconRAMDisk: return "RAMDisk"
-	case IconCD: return "CD"
-	case IconDVD: return "DVD"
-	case IconNetwork: return "Network"
-	case IconLocalNetwork: return "LocalNetwork"
-	case IconInternet: return "Internet"
-	case IconEthernet: return "Ethernet"
-	case IconWireless: return "Wireless"
-	case IconCell: return "Cell"
-	case IconBluetooth: return "Bluetooth"
-	case IconRadio: return "Radio"
-	case IconDevice: return "Device"
-	case IconRouter: return "Router"
-	case IconServer: return "Server"
-	case IconDesktop: return "Desktop"
-	case IconLaptop: return "Laptop"
-	case IconTablet: return "Tablet"
-	case IconPhone: return "Phone"
-	case IconWatch: return "Watch"
-	case IconCamera: return "Camera"
-	case IconPeripheral: return "Peripheral"
-	case IconKeyboard: return "Keyboard"
-	case IconMouse: return "Mouse"
-	case IconMonitor: return "Monitor"
-	case IconWebcam: return "Webcam"
-	case IconMicrophone: return "Microphone"
-	case IconSpeaker: return "Speaker"
-	case IconPenTablet: return "PenTablet"
-	case IconTrackpad: return "Trackpad"
-	case IconController: return "Controller"
-	case IconPort: return "Port"
-	case IconEthernetPort: return "EthernetPort"
-	case IconUSBPort: return "USBPort"
-	case IconParallelPort: return "ParallelPort"
-	case IconSerialPort: return "SerialPort"
-	case IconPS2Port: return "PS2Port"
-	case IconDisplayConnector: return "DisplayConnector"
-	case IconCGAPort: return "CGAPort"
-	case IconVGAPort: return "VGAPort"
-	case IconHDMIPort: return "HDMIPort"
-	case IconDisplayPort: return "DisplayPort"
-	case IconInfrared: return "Infrared"
-	case IconOpen: return "Open"
-	case IconOpenIn: return "OpenIn"
-	case IconSave: return "Save"
-	case IconSaveAs: return "SaveAs"
-	case IconPrint: return "Print"
-	case IconNew: return "New"
-	case IconNewDirectory: return "NewDirectory"
-	case IconDelete: return "Delete"
-	case IconRename: return "Rename"
-	case IconGetInformation: return "GetInformation"
-	case IconChangePermissions: return "ChangePermissions"
-	case IconRevert: return "Revert"
-	case IconAdd: return "Add"
-	case IconRemove: return "Remove"
-	case IconAddBookmark: return "AddBookmark"
-	case IconRemoveBookmark: return "RemoveBookmark"
-	case IconAddFavorite: return "AddFavorite"
-	case IconRemoveFavorite: return "RemoveFavorite"
-	case IconPlay: return "Play"
-	case IconPause: return "Pause"
-	case IconStop: return "Stop"
-	case IconFastForward: return "FastForward"
-	case IconRewind: return "Rewind"
-	case IconToBeginning: return "ToBeginning"
-	case IconToEnd: return "ToEnd"
-	case IconRecord: return "Record"
-	case IconVolumeUp: return "VolumeUp"
-	case IconVolumeDown: return "VolumeDown"
-	case IconMute: return "Mute"
-	case IconUndo: return "Undo"
-	case IconRedo: return "Redo"
-	case IconCut: return "Cut"
-	case IconCopy: return "Copy"
-	case IconPaste: return "Paste"
-	case IconFind: return "Find"
-	case IconReplace: return "Replace"
-	case IconSelectAll: return "SelectAll"
-	case IconSelectNone: return "SelectNone"
-	case IconIncrement: return "Increment"
-	case IconDecrement: return "Decrement"
-	case IconClose: return "Close"
-	case IconQuit: return "Quit"
-	case IconIconify: return "Iconify"
-	case IconShade: return "Shade"
-	case IconMaximize: return "Maximize"
-	case IconFullScreen: return "FullScreen"
-	case IconRestore: return "Restore"
-	case IconExpand: return "Expand"
-	case IconContract: return "Contract"
-	case IconBack: return "Back"
-	case IconForward: return "Forward"
-	case IconUp: return "Up"
-	case IconDown: return "Down"
-	case IconReload: return "Reload"
-	case IconZoomIn: return "ZoomIn"
-	case IconZoomOut: return "ZoomOut"
-	case IconZoomReset: return "ZoomReset"
-	case IconMove: return "Move"
-	case IconResize: return "Resize"
-	case IconGoTo: return "GoTo"
-	case IconTransform: return "Transform"
-	case IconTranslate: return "Translate"
-	case IconRotate: return "Rotate"
-	case IconScale: return "Scale"
-	case IconWarp: return "Warp"
-	case IconCornerPin: return "CornerPin"
-	case IconSelectRectangle: return "SelectRectangle"
-	case IconSelectEllipse: return "SelectEllipse"
-	case IconSelectLasso: return "SelectLasso"
-	case IconSelectGeometric: return "SelectGeometric"
-	case IconSelectAuto: return "SelectAuto"
-	case IconCrop: return "Crop"
-	case IconFill: return "Fill"
-	case IconGradient: return "Gradient"
-	case IconPencil: return "Pencil"
-	case IconBrush: return "Brush"
-	case IconEraser: return "Eraser"
-	case IconText: return "Text"
-	case IconEyedropper: return "Eyedropper"
-	case IconInformation: return "Information"
-	case IconQuestion: return "Question"
-	case IconWarning: return "Warning"
-	case IconError: return "Error"
-	case IconCancel: return "Cancel"
-	case IconOkay: return "Okay"
-	case IconCellSignal0: return "CellSignal0"
-	case IconCellSignal1: return "CellSignal1"
-	case IconCellSignal2: return "CellSignal2"
-	case IconCellSignal3: return "CellSignal3"
-	case IconWirelessSignal0: return "WirelessSignal0"
-	case IconWirelessSignal1: return "WirelessSignal1"
-	case IconWirelessSignal2: return "WirelessSignal2"
-	case IconWirelessSignal3: return "WirelessSignal3"
-	case IconBattery0: return "Battery0"
-	case IconBattery1: return "Battery1"
-	case IconBattery2: return "Battery2"
-	case IconBattery3: return "Battery3"
-	case IconBrightness0: return "Brightness0"
-	case IconBrightness1: return "Brightness1"
-	case IconBrightness2: return "Brightness2"
-	case IconBrightness3: return "Brightness3"
-	case IconVolume0: return "Volume0"
-	case IconVolume1: return "Volume1"
-	case IconVolume2: return "Volume2"
-	case IconVolume3: return "Volume3"
-
-	default: return "Unknown"
-	}
-}
-
-// Texture returns a texture of the corresponding icon ID.
-func (id Icon) Texture (size IconSize) canvas.Texture {
-	if current == nil { return nil }
-	return current.Icon(id, size)
-}
-
-// MimeIcon returns an icon corresponding to a MIME type.
-func MimeIcon (mime data.Mime, size IconSize) canvas.Texture {
-	if current == nil { return nil }
-	return current.MimeIcon(mime, size)
-}
-
-// ApplicationIcon describes the icon of the application.
-type ApplicationIcon tomo.ApplicationDescription
-
-// Texture returns a texture of the corresponding icon ID.
-func (icon ApplicationIcon) Texture (size IconSize) canvas.Texture {
-	if current == nil { return nil }
-	return current.ApplicationIcon(icon, size)
-}

tomo.go

@@ -12,13 +12,11 @@ var backend Backend
 // event loop in that order. This function blocks until Stop is called, or the
 // backend experiences a fatal error.
 func Run (callback func ()) error {
-	loadPlugins()
-
 	if backend != nil {
 		return errors.New("there is already a backend running")
 	}
 
-	back, err := Initialize()
+	back, err := initialize()
 	if err != nil { return err }
 	
 	backendLock.Lock()
@@ -57,6 +55,14 @@ func NewWindow (bounds image.Rectangle) (MainWindow, error) {
 	return backend.NewWindow(bounds)
 }
 
+// NewPlainWindow is like NewWindow, but it creates an undecorated window that
+// does not appear in window lists. It is intended for creating things like
+// docks, panels, etc.
+func NewPlainWindow (bounds image.Rectangle) (MainWindow, error) {
+	assertBackend()
+	return backend.NewPlainWindow(bounds)
+}
+
 // NewBox creates and returns a basic Box.
 func NewBox () Box {
 	assertBackend()

unix.go

@@ -1,26 +0,0 @@
-//go:build linux || darwin || freebsd
-
-package tomo
-
-import "os"
-import "strings"
-import "path/filepath"
-
-var userDataDir string
-
-func init () {
-	pathVariable := os.Getenv("TOMO_PLUGIN_PATH")
-	pluginPaths = strings.Split(pathVariable, ":")
-	pluginPaths = append (
-		pluginPaths,
-		"/usr/lib/tomo/plugins",
-		"/usr/local/lib/tomo/plugins")
-	homeDir, err := os.UserHomeDir()
-	if err == nil {
-		pluginPaths = append (
-			pluginPaths,
-			filepath.Join(homeDir, ".local/lib/tomo/plugins"))
-	}
-
-	userDataDir = filepath.Join(homeDir, ".local/share")
-}