Change clip behaviors to sub behaviors

Remedies #4

.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

@@ -1,6 +1,8 @@
 # tomo
 
-WIP rewrite of tomo.
+[![Go Reference](https://pkg.go.dev/badge/git.tebibyte.media/tomo/tomo.svg)](https://pkg.go.dev/git.tebibyte.media/tomo/tomo)
 
-This module will serve as a wafer-thin collection of interfaces and glue code so
-that plugins will be an actual viable concept.
+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.

backend.go

@@ -3,6 +3,7 @@ package tomo
 import "sort"
 import "image"
 import "errors"
+import "git.tebibyte.media/tomo/tomo/canvas"
 
 // Backend is any Tomo implementation. Backends handle window creation, layout,
 // rendering, and events so that there can be as many platform-specific
@@ -10,15 +11,22 @@ import "errors"
 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
 	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) Texture
+	NewTexture (image.Image) canvas.TextureCloser
 
 	// Run runs the event loop until Stop() is called, or the backend
 	// experiences a fatal error.

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.
@@ -30,22 +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
+	// 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.
@@ -55,8 +71,10 @@ 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.

canvas/texture.go

@@ -0,0 +1,21 @@
+package canvas
+
+import "io"
+import "image"
+
+// Texture is a handle that points to a 2D raster image managed by the backend.
+type Texture interface {
+	image.Image
+
+	// 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
+// TextureCloser must close it after use.
+type TextureCloser interface {
+	Texture
+	io.Closer
+}

object.go

@@ -101,7 +101,7 @@ type Align int; const (
 	AlignEven               // similar to justified text
 )
 
-// Object is any obscreen object. Each object must be linked to a box, even if
+// Object is any onscreen object. Each object must be linked to a box, even if
 // it is that box.
 type Object interface {
 	GetBox () Box
@@ -112,13 +112,13 @@ 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 +126,36 @@ 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)
+	SetColor (color.Color)
 	// SetTexture sets a repeating background texture. If the texture is
 	// transparent, it will be overlayed atop the color specified by
 	// SetColor().
-	SetTexture     (Texture)
+	SetTexture (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)
+	// 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
 
 	// 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 +163,16 @@ 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
@@ -195,8 +201,13 @@ 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.
@@ -211,16 +222,16 @@ type ContentBox interface {
 	// 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 +242,26 @@ 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 +269,35 @@ 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 +305,14 @@ 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 +324,44 @@ 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.

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
-}

texture.go

@@ -1,29 +0,0 @@
-package tomo
-
-import "io"
-import "image"
-
-// Texture is a handle that points to a 2D raster image managed by the backend.
-type Texture interface {
-	io.Closer
-
-	// Clip returns a smaller section of this texture, pointing to the same
-	// internal data. Becaue of this, closing a clipped section will close
-	// the original texture as well.
-	Clip (image.Rectangle) Texture
-}
-
-type protectedTexture struct {
-	Texture
-}
-
-func (protectedTexture) Close () error {
-	return nil
-}
-
-// Protect makes the Close() method of a texture do nothing. This is useful if
-// several of the same texture are given out to different objects, but only one
-// has the responsibility of closing it.
-func Protect (texture Texture) Texture {
-	return protectedTexture { Texture: texture }
-}

theme/icon.go

@@ -1,7 +1,7 @@
 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 (
@@ -10,284 +10,269 @@ type IconSize int; const (
 	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 int; const (
-	// --- Objects --- //
+type Icon string
 
-	// 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
-	IconPrints
-	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
+// A list of standard icon IDs.
+const (
+	IconUnknown                      Icon = ""
 
-	// 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
+	// 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) tomo.Texture {
+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) tomo.Texture {
+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 struct {
-	// The name or ID of the application. If applicable, this should
-	// correspond to the file name (without the path or extension) of the
-	// icon on the system. This field is optional.
-	Name string
-	
-	// Role describes what the application does. If a specific icon file
-	// cannot be found, a generic one is picked using this field.
-	Role ApplicationRole
-}
-
-// Texture returns a texture of the corresponding icon ID.
-func (icon ApplicationIcon) Texture (size IconSize) tomo.Texture {
-	if current == nil { return nil }
-	return current.ApplicationIcon(icon, size)
-}
-
-// 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
-)

theme/theme.go

@@ -1,15 +1,17 @@
 package theme
 
+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"
 
 // Role describes the role of an object.
 type Role struct {
 	// Package is an optional namespace field. If specified, it should be
 	// the package name or module name the object is from.
 	Package string
-	
+
 	// Object specifies what type of object it is. For example:
 	//   - TextInput
 	//   - Table
@@ -17,17 +19,24 @@ type Role struct {
 	//   - Dial
 	// This should correspond directly to the type name of the object.
 	Object string
-	
+
 	// Variant is an optional field to be used when an object has one or
 	// more soft variants under one type. For example, an object "Slider"
 	// may have variations "horizontal" and "vertical".
 	Variant string
 }
 
+// String satisfies the fmt.Stringer interface.
+// It follows the format of:
+// Package.Object[Variant]
+func (r Role) String () string {
+	return fmt.Sprintf("%s.%s[%s]", r.Package, r.Object, r.Variant)
+}
+
 // R is shorthand for creating a Role structure.
 func R (pack, object, variant string) Role {
 	return Role { Package: pack, Object: object, Variant: variant }
-} 
+}
 
 // Color represents a color ID.
 type Color int; const (
@@ -38,36 +47,50 @@ type Color int; const (
 	ColorAccent
 )
 
+// String satisfies the fmt.Stringer interface.
+func (c Color) String () string {
+	switch c {
+	case ColorBackground: return "background"
+	case ColorForeground: return "foreground"
+	case ColorRaised:     return "raised"
+	case ColorSunken:     return "sunken"
+	case ColorAccent:     return "accent"
+	default:              return "unknown"
+	}
+}
+
 // RGBA satisfies the color.Color interface.
 func (id Color) RGBA () (r, g, b, a uint32) {
 	if current == nil { return }
 	return current.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:
+	//
+	// Because textures can be linked to some resource that is outside of
+	// the control of Go's garbage collector, methods of Theme must not
+	// allocate new copies of a texture each time they are called. It is
+	// fine to lazily load textures and save them for later use, but the
+	// same texture must never be allocated multiple times as this could
+	// cause a memory leak.
+	//
+	// 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 will remove them.
+	// closing the returned cookie must remove them.
 	Apply (tomo.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. This texture
-	// should be protected, unless a new copy of it is returned with each
-	// subsequent call.
-	Icon (Icon, IconSize) tomo.Texture
-	
-	// MimeIcon returns an icon corresponding to a MIME type. This texture
-	// should be protected, unless a new copy of it is returned with each
-	// subsequent call.
-	MimeIcon (data.Mime, IconSize) tomo.Texture
-	
-	// ApplicationIcon returns an icon corresponding to an application. This
-	// texture should be protected, unless a new copy of it is returned with
-	// each subsequent call.
-	ApplicationIcon (ApplicationIcon, IconSize) tomo.Texture
+
+	// Icon returns a texture of the corresponding icon ID.
+	Icon (Icon, IconSize) canvas.Texture
+
+	// MimeIcon returns an icon corresponding to a MIME type.
+	MimeIcon (data.Mime, IconSize) canvas.Texture
 }
 
 var current Theme
@@ -84,4 +107,3 @@ func Apply (object tomo.Object, role Role) event.Cookie {
 	if current == nil { return event.NoCookie { } }
 	return current.Apply(object, role)
 }
-

tomo.go

@@ -3,6 +3,7 @@ package tomo
 import "sync"
 import "image"
 import "errors"
+import "git.tebibyte.media/tomo/tomo/canvas"
 
 var backendLock sync.Mutex
 var backend Backend
@@ -11,8 +12,6 @@ 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")
 	}
@@ -56,6 +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()
@@ -82,7 +89,7 @@ func NewContainerBox () ContainerBox {
 
 // NewTexture creates a new texture from an image. When no longer in use, it
 // must be freed using Close().
-func NewTexture (source image.Image) Texture {
+func NewTexture (source image.Image) canvas.TextureCloser {
 	assertBackend()
 	return backend.NewTexture(source)
 }

unix.go

@@ -1,22 +0,0 @@
-//go:build linux || darwin || freebsd
-
-package tomo
-
-import "os"
-import "strings"
-import "path/filepath"
-
-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"))
-	}
-}