Roles are stored in Boxes now

Remedy #15

backend.go

@@ -29,6 +29,10 @@ type Backend interface {
 	// reject any texture that was not made by it.
 	NewTexture (image.Image) canvas.TextureCloser
 
+	// NewCanvas creates a new canvas with the specified bounds. The backend
+	// must reject any canvas that was not made by it.
+	NewCanvas (image.Rectangle) canvas.CanvasCloser
+
 	// Run runs the event loop until Stop() is called, or the backend
 	// experiences a fatal error.
 	Run () error
@@ -60,11 +64,11 @@ 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

@@ -2,6 +2,7 @@
 // primitives.
 package canvas
 
+import "io"
 import "image"
 import "image/draw"
 import "image/color"
@@ -77,6 +78,13 @@ type Canvas interface {
 	SubCanvas (image.Rectangle) Canvas
 }
 
+// CanvasCloser is a canvas that can be closed. Anything that receives a
+// CanvasCloser must close it after use.
+type CanvasCloser interface {
+	Canvas
+	io.Closer
+}
+
 // Drawer can draw to a canvas.
 type Drawer interface {
 	// Draw draws to the given canvas.

go.sum

@@ -1,8 +1,6 @@
 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=
-golang.org/x/image v0.8.0 h1:agUcRXV/+w6L9ryntYYsF2x9fQTMd4T8fiiYXAVW6Jg=
-golang.org/x/image v0.8.0/go.mod h1:PwLxp3opCYg4WR2WO9P0L6ESnsD6bLTWcw8zanLMVFM=
 golang.org/x/image v0.11.0 h1:ds2RoQvBvYTiJkwpSFDwCcDFNX7DqjL2WsUgTNk0Ooo=
 golang.org/x/image v0.11.0/go.mod h1:bglhjqbqVuEb9e9+eNR45Jfu7D+T4Qan+NhQk8Ck2P8=
 golang.org/x/mod v0.6.0-dev.0.20220419223038-86c51ed26bb4/go.mod h1:jJ57K6gSWd91VN4djpZkiMVwK6gcyfeH4XE8wZrZaV4=
@@ -27,7 +25,6 @@ golang.org/x/text v0.3.0/go.mod h1:NqM8EUOU14njkJ3fqMW+pc6Ldnwhi/IjpwHt7yyuwOQ=
 golang.org/x/text v0.3.3/go.mod h1:5Zoc/QRtKVWzQhOtBMvqHzDpF6irO9z98xDceosuGiQ=
 golang.org/x/text v0.3.7/go.mod h1:u+2+/6zg+i71rQMx5EYifcz6MCKuco9NR6JIITiCfzQ=
 golang.org/x/text v0.7.0/go.mod h1:mrYo+phRRbMaCq/xk9113O4dZlRixOauAjOtrjsXDZ8=
-golang.org/x/text v0.10.0/go.mod h1:TvPlkZtksWOMsz7fbANvkp4WM8x/WCo/om8BMLbz+aE=
 golang.org/x/text v0.12.0/go.mod h1:TvPlkZtksWOMsz7fbANvkp4WM8x/WCo/om8BMLbz+aE=
 golang.org/x/tools v0.0.0-20180917221912-90fa682c2a6e/go.mod h1:n7NCudcB/nEzxVGmLbDWY5pfWTLqBcC2KZ6jyYvM4mQ=
 golang.org/x/tools v0.0.0-20191119224855-298f0cb1881e/go.mod h1:b+2E5dAYhXwXZwtnZ6UAqBI28+e2cm9otk0dWdXHAEo=

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

@@ -102,8 +102,8 @@ type Align int; const (
 )
 
 // Object is any onscreen object that is linked to a box (or is that box).
-// Unlike the Box interface and associated interfaces, Object interfaces may
-// originate from anywhere.
+// Unlike the Box interface and associated interfaces, Object implementations
+// may originate from anywhere.
 type Object interface {
 	GetBox () Box
 }
@@ -123,8 +123,8 @@ type ContentObject interface {
 	OnContentBoundsChange (func ()) event.Cookie
 }
 
-// Box is a basic styled box. Box, as well as any interface that embeds Box, may
-// only originate from a Backend.
+// 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
 
@@ -144,15 +144,23 @@ type Box interface {
 	//     internal content that does not overflow, the size of that is also
 	//     taken into account here.
 	MinimumSize () image.Point
+	// Role returns this Box's role as set by SetRole.
+	Role () Role
 	// SetBounds sets the bounding rectangle of this Box relative to the
 	// Window.
 	SetBounds (image.Rectangle)
 	// SetColor sets the background color of this Box.
 	SetColor (color.Color)
-	// SetTexture sets a repeating background texture. If the texture is
+	// 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)
@@ -162,12 +170,9 @@ type Box interface {
 	// SetPadding sets the padding between the Box's innermost Border and
 	// its content.
 	SetPadding (Inset)
-	// SetVisible sets whether or not this box is visible. If invisible,
-	// it will not be drawn and no space will be created for it in the
-	// layout. Boxes are visible by default.
-	SetVisible (bool)
-	// Visible returns whether or not this box is visible.
-	Visible () bool
+	// SetRole sets what role this Box takes on. It is used to apply styling
+	// from a theme.
+	SetRole (Role)
 
 	// 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
@@ -244,9 +249,16 @@ type SurfaceBox interface {
 	// 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 causes the data within the surface to be pushed to the
+	// screen at the end of the event cycle, even if it wouldn't be
+	// otherwise.
 	Invalidate ()
+
+	// OnSizeChange specifies a function to be called when the size of the
+	// Box is changed, or the surface is re-allocated. The application must
+	// call Surface() each time this event fires in order to not draw to a
+	// closed surface.
+	OnSizeChange (func ())
 }
 
 // ContentBox is a box that has some kind of content.

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"
@@ -61,8 +60,8 @@ 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 can apply a visual style to different objects.
@@ -78,32 +77,35 @@ type Theme interface {
 	//
 	// As such, textures returned by these methods must be protected.
 	
-	// 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 applies the theme to the given object, according to its role.
+	// This may register event listeners with the given object; closing the
+	// returned cookie must remove them.
+	Apply (Object) 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
 }
 
-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)
+// Apply applies the current theme to the given object, according its role. This
+// may register event listeners with the given object; closing the returned
+// cookie will remove them.
+func Apply (object Object) event.Cookie {
+	if theme == nil { return event.NoCookie { } }
+	return theme.Apply(object)
 }

theme/icon.go

@@ -1,278 +0,0 @@
-package theme
-
-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.
-const (
-	IconUnknown                      Icon = ""
-
-	// objects: files
-	IconFile                         Icon = "File" // generic
-	IconDirectory                    Icon = "Directory"
-	IconDirectoryFull                Icon = "DirectoryFull"
-
-	// objects: places
-	IconPlaceHome                    Icon = "PlaceHome"
-	IconPlaceDownloads               Icon = "PlaceDownloads"
-	IconPlacePhotos                  Icon = "PlacePhotos"
-	IconPlaceBooks                   Icon = "PlaceBooks"
-	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"
-
-	// objects: storage
-	IconStorage                      Icon = "Storage" // generic
-	IconStorageMagneticTape          Icon = "StorageMagneticTape"
-	IconStorageFloppyDisk            Icon = "StorageFloppyDisk"
-	IconStorageHardDisk              Icon = "StorageHardDisk"
-	IconStorageSolidStateDisk        Icon = "StorageSolidState"
-	IconStorageFlashStick            Icon = "StorageFlashStick"
-	IconStorageFlashCard             Icon = "StorageFlashCard"
-	IconStorageROM                   Icon = "StorageROM"
-	IconStorageRAM                   Icon = "StorageRAM"
-	IconStorageCD                    Icon = "StorageCD"
-	IconStorageDVD                   Icon = "StorageDVD"
-
-	// objects: 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"
-
-	// objects: networks
-	IconNetwork                      Icon = "Network" // generic
-	IconNetworkLocal                 Icon = "NetworkLocal"
-	IconNetworkInternet              Icon = "NetworkInternet"
-	IconNetworkEthernet              Icon = "NetworkEthernet"
-	IconNetworkWireless              Icon = "NetworkWireless"
-	IconNetworkCell                  Icon = "NetworkCell"
-	IconNetworkBluetooth             Icon = "NetworkBluetooth"
-	IconNetworkRadio                 Icon = "NetworkRadio"
-
-	// objects: devices
-	IconDevice                       Icon = "Device" // generic
-	IconDeviceRouter                 Icon = "DeviceRouter"
-	IconDeviceServer                 Icon = "DeviceServer"
-	IconDeviceDesktop                Icon = "DeviceDesktop"
-	IconDeviceLaptop                 Icon = "DeviceLaptop"
-	IconDeviceTablet                 Icon = "DeviceTablet"
-	IconDevicePhone                  Icon = "DevicePhone"
-	IconDeviceWatch                  Icon = "DeviceWatch"
-	IconDeviceCamera                 Icon = "DeviceCamera"
-
-	// objects: peripherals
-	IconPeripheral                   Icon = "Peripheral" // generic
-	IconPeripheralKeyboard           Icon = "PeripheralKeyboard"
-	IconPeripheralMouse              Icon = "PeripheralMouse"
-	IconPeripheralMonitor            Icon = "PeripheralMonitor"
-	IconPeripheralWebcam             Icon = "PeripheralWebcam"
-	IconPeripheralMicrophone         Icon = "PeripheralMicrophone"
-	IconPeripheralSpeaker            Icon = "PeripheralSpeaker"
-	IconPeripheralPenTablet          Icon = "PeripheralPenTablet"
-	IconPeripheralTrackpad           Icon = "PeripheralTrackpad"
-	IconPeripheralController         Icon = "PeripheralController"
-
-	// objects: i/o
-	IconPort                         Icon = "Port" // generic
-	IconPortEthernet                 Icon = "PortEthernet"
-	IconPortUSB                      Icon = "PortUSB"
-	IconPortParallel                 Icon = "PortParallel"
-	IconPortSerial                   Icon = "PortSerial"
-	IconPortPS2                      Icon = "PortPS2"
-	IconPortDisplay                  Icon = "PortDisplay"
-	IconPortCGA                      Icon = "PortCGA"
-	IconPortVGA                      Icon = "PortVGA"
-	IconPortHDMI                     Icon = "PortHDMI"
-	IconPortDisplayPort              Icon = "PortDisplayPort"
-	IconPortInfrared                 Icon = "PortInfrared"
-
-	// actions: files
-	IconActionOpen                   Icon = "ActionOpen"
-	IconActionOpenIn                 Icon = "ActionOpenIn"
-	IconActionSave                   Icon = "ActionSave"
-	IconActionSaveAs                 Icon = "ActionSaveAs"
-	IconActionPrint                  Icon = "ActionPrint"
-	IconActionNew                    Icon = "ActionNew"
-	IconActionNewDirectory           Icon = "ActionNewDirectory"
-	IconActionDelete                 Icon = "ActionDelete"
-	IconActionRename                 Icon = "ActionRename"
-	IconActionGetInformation         Icon = "ActionGetInformation"
-	IconActionChangePermissions      Icon = "ActionChangePermissions"
-	IconActionRevert                 Icon = "ActionRevert"
-
-	// actions: list management
-	IconActionAdd                    Icon = "ActionAdd"
-	IconActionRemove                 Icon = "ActionRemove"
-	IconActionAddBookmark            Icon = "ActionAddBookmark"
-	IconActionRemoveBookmark         Icon = "ActionRemoveBookmark"
-	IconActionAddFavorite            Icon = "ActionAddFavorite"
-	IconActionRemoveFavorite         Icon = "ActionRemoveFavorite"
-
-	// actions: media
-	IconActionPlay                   Icon = "ActionPlay"
-	IconActionPause                  Icon = "ActionPause"
-	IconActionStop                   Icon = "ActionStop"
-	IconActionFastForward            Icon = "ActionFastForward"
-	IconActionRewind                 Icon = "ActionRewind"
-	IconActionToBeginning            Icon = "ActionToBeginning"
-	IconActionToEnd                  Icon = "ActionToEnd"
-	IconActionRecord                 Icon = "ActionRecord"
-	IconActionVolumeUp               Icon = "ActionVolumeUp"
-	IconActionVolumeDown             Icon = "ActionVolumeDown"
-	IconActionMute                   Icon = "ActionMute"
-
-	// actions: editing
-	IconActionUndo                   Icon = "ActionUndo"
-	IconActionRedo                   Icon = "ActionRedo"
-	IconActionCut                    Icon = "ActionCut"
-	IconActionCopy                   Icon = "ActionCopy"
-	IconActionPaste                  Icon = "ActionPaste"
-	IconActionFind                   Icon = "ActionFind"
-	IconActionReplace                Icon = "ActionReplace"
-	IconActionSelectAll              Icon = "ActionSelectAll"
-	IconActionSelectNone             Icon = "ActionSelectNone"
-	IconActionIncrement              Icon = "ActionIncrement"
-	IconActionDecrement              Icon = "ActionDecrement"
-
-	// actions: window management
-	IconActionClose                  Icon = "ActionClose"
-	IconActionQuit                   Icon = "ActionQuit"
-	IconActionIconify                Icon = "ActionIconify"
-	IconActionShade                  Icon = "ActionShade"
-	IconActionMaximize               Icon = "ActionMaximize"
-	IconActionFullScreen             Icon = "ActionFullScreen"
-	IconActionRestore                Icon = "ActionRestore"
-
-	// actions: view
-	IconActionExpand                 Icon = "ActionExpand"
-	IconActionContract               Icon = "ActionContract"
-	IconActionBack                   Icon = "ActionBack"
-	IconActionForward                Icon = "ActionForward"
-	IconActionUp                     Icon = "ActionUp"
-	IconActionDown                   Icon = "ActionDown"
-	IconActionReload                 Icon = "ActionReload"
-	IconActionZoomIn                 Icon = "ActionZoomIn"
-	IconActionZoomOut                Icon = "ActionZoomOut"
-	IconActionZoomReset              Icon = "ActionZoomReset"
-	IconActionMove                   Icon = "ActionMove"
-	IconActionResize                 Icon = "ActionResize"
-	IconActionGoTo                   Icon = "ActionGoTo"
-
-	// actions: tools
-	IconActionTransform              Icon = "ActionTransform"
-	IconActionTranslate              Icon = "ActionTranslate"
-	IconActionRotate                 Icon = "ActionRotate"
-	IconActionScale                  Icon = "ActionScale"
-	IconActionWarp                   Icon = "ActionWarp"
-	IconActionCornerPin              Icon = "ActionCornerPin"
-	IconActionSelectRectangle        Icon = "ActionSelectRectangle"
-	IconActionSelectEllipse          Icon = "ActionSelectEllipse"
-	IconActionSelectLasso            Icon = "ActionSelectLasso"
-	IconActionSelectGeometric        Icon = "ActionSelectGeometric"
-	IconActionSelectAuto             Icon = "ActionSelectAuto"
-	IconActionCrop                   Icon = "ActionCrop"
-	IconActionFill                   Icon = "ActionFill"
-	IconActionGradient               Icon = "ActionGradient"
-	IconActionPencil                 Icon = "ActionPencil"
-	IconActionBrush                  Icon = "ActionBrush"
-	IconActionEraser                 Icon = "ActionEraser"
-	IconActionText                   Icon = "ActionText"
-	IconActionEyedropper             Icon = "ActionEyedropper"
-
-	// status: dialog
-	IconStatusInformation            Icon = "StatusInformation"
-	IconStatusQuestion               Icon = "StatusQuestion"
-	IconStatusWarning                Icon = "StatusWarning"
-	IconStatusError                  Icon = "StatusError"
-	IconStatusCancel                 Icon = "StatusCancel"
-	IconStatusOkay                   Icon = "StatusOkay"
-
-	// status: network
-	IconStatusCellSignal0            Icon = "StatusCellSignal0"
-	IconStatusCellSignal1            Icon = "StatusCellSignal1"
-	IconStatusCellSignal2            Icon = "StatusCellSignal2"
-	IconStatusCellSignal3            Icon = "StatusCellSignal3"
-	IconStatusWirelessSignal0        Icon = "StatusWirelessSignal0"
-	IconStatusWirelessSignal1        Icon = "StatusWirelessSignal1"
-	IconStatusWirelessSignal2        Icon = "StatusWirelessSignal2"
-	IconStatusWirelessSignal3        Icon = "StatusWirelessSignal3"
-
-	// status: power
-	IconStatusBattery0               Icon = "StatusBattery0"
-	IconStatusBattery1               Icon = "StatusBattery1"
-	IconStatusBattery2               Icon = "StatusBattery2"
-	IconStatusBattery3               Icon = "StatusBattery3"
-	IconStatusBrightness0            Icon = "StatusBrightness0"
-	IconStatusBrightness1            Icon = "StatusBrightness1"
-	IconStatusBrightness2            Icon = "StatusBrightness2"
-	IconStatusBrightness3            Icon = "StatusBrightness3"
-
-	// status: media
-	IconStatusVolume0                Icon = "StatusVolume0"
-	IconStatusVolume1                Icon = "StatusVolume1"
-	IconStatusVolume2                Icon = "StatusVolume2"
-	IconStatusVolume3                Icon = "StatusVolume3"
-)
-
-// 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)
-}

tomo.go

@@ -16,7 +16,7 @@ func Run (callback func ()) error {
 		return errors.New("there is already a backend running")
 	}
 
-	back, err := Initialize()
+	back, err := initialize()
 	if err != nil { return err }
 	
 	backendLock.Lock()
@@ -93,3 +93,10 @@ func NewTexture (source image.Image) canvas.TextureCloser {
 	assertBackend()
 	return backend.NewTexture(source)
 }
+
+// NewCanvas creates a new canvas with the specified bounds. When no longer in
+// use, it must be freed using Close().
+func NewCanvas (bounds image.Rectangle) canvas.CanvasCloser {
+	assertBackend()
+	return backend.NewCanvas(bounds)
+}