Add function keys up to F24

backend.go

@@ -4,18 +4,26 @@ import "sort"
 import "image"
 import "errors"
 
+// Backend is any Tomo implementation. Backends handle window creation, layout,
+// rendering, and events so that there can be as many platform-specific
+// optimizations as possible.
 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
 
+	// Run runs the event loop until Stop() is called, or the backend
+	// experiences a fatal error.
+	Run () error
+	
 	// Stop must unblock run.
-	Run  () error
 	Stop ()
 
-	// Do performs a callback function in the main thread as soon as
+	// Do performs a callback function in the event loop thread as soon as
 	// possible. This method must be safe to call concurrently.
 	Do (func ())
 }

canvas/canvas.go

@@ -8,24 +8,24 @@ import "image/color"
 
 // Cap represents a stroke cap type.
 type Cap int; const (
-	CapButt Cap = iota
-	CapRound
-	CapSquare
+	CapButt Cap = iota // Square cap that ends at the point
+	CapRound           // Round cap that surrounds the point
+	CapSquare          // square cap that surrounds the point
 )
 
 // Joint represents a stroke joint type.
 type Joint int; const (
-	JointRount Joint = iota
-	JointSharp
-	JointMiter
+	JointRount Joint = iota // Rounded joint
+	JointSharp              // Sharp joint
+	JointMiter              // Clipped/beveled joint
 )
 
 // StrokeAlign determines whether a stroke is drawn inside, outside, or on a
 // path.
 type StrokeAlign int; const (
-	StrokeAlignCenter StrokeAlign = iota
-	StrokeAlignInner
-	StrokeAlignOuter
+	StrokeAlignCenter StrokeAlign = iota // Centered on the path
+	StrokeAlignInner                     // Inset into the path
+	StrokeAlignOuter                     // Outset around the path
 )
 
 // Pen represents a drawing context that is linked to a canvas. Each canvas can
@@ -44,9 +44,8 @@ type Pen interface {
 	StrokeWeight (int)         // how thick the stroke is
 	StrokeAlign  (StrokeAlign) // where the stroke is drawn
 
-	// set the stroke/fill to a solid color
-	Stroke (color.Color)
-	Fill   (color.Color)
+	Stroke (color.Color) // Sets the stroke to a solid color
+	Fill   (color.Color) // Sets the fill to a solid color
 }
 
 // Canvas is an image that supports drawing paths.
@@ -62,6 +61,7 @@ type Canvas interface {
 
 // Drawer is an object that can draw to a canvas.
 type Drawer interface {
+	// Draw draws to the given canvas.
 	Draw (Canvas)
 }
 

data/data.go

@@ -27,7 +27,10 @@ func (mime Mime) String () string {
 	return mime.Type + "/" + mime.Subtype
 }
 
+// MimePlain returns the MIME type of plain text.
 func MimePlain () Mime { return Mime { "text", "plain"    } }
+
+// MimeFile returns the MIME type of a file path/URI.
 func MimeFile  () Mime { return Mime { "text", "uri-list" } }
 
 type byteReadCloser struct { *bytes.Reader }

input/input.go

@@ -59,6 +59,18 @@ const (
 	KeyF10 Key = 138
 	KeyF11 Key = 139
 	KeyF12 Key = 140
+	KeyF13 Key = 141
+	KeyF14 Key = 142
+	KeyF15 Key = 143
+	KeyF16 Key = 144
+	KeyF17 Key = 145
+	KeyF18 Key = 146
+	KeyF19 Key = 147
+	KeyF20 Key = 148
+	KeyF21 Key = 149
+	KeyF22 Key = 150
+	KeyF23 Key = 151
+	KeyF24 Key = 152
 )
 
 // Button represents a mouse button.

object.go

@@ -3,13 +3,12 @@ package tomo
 import "image"
 import "image/color"
 import "golang.org/x/image/font"
+import "git.tebibyte.media/tomo/tomo/text"
 import "git.tebibyte.media/tomo/tomo/data"
 import "git.tebibyte.media/tomo/tomo/event"
 import "git.tebibyte.media/tomo/tomo/input"
 import "git.tebibyte.media/tomo/tomo/canvas"
 
-type Gap image.Point
-
 // Side represents one side of a rectangle.
 type Side int; const (
 	SideTop Side = iota
@@ -18,6 +17,8 @@ type Side int; const (
 	SideLeft
 )
 
+// Inset represents a rectangle inset that can have a different value for each
+// side.
 type Inset [4]int
 
 // I allows you to create an inset in a CSS-ish way:
@@ -86,11 +87,13 @@ func (inset Inset) Vertical () int {
 	return inset[SideTop] + inset[SideBottom]
 }
 
+// Border represents a single border of a box.
 type Border struct {
 	Width Inset
 	Color [4]color.Color
 }
 
+// Align lists basic alignment types.
 type Align int; const (
 	AlignStart Align = iota // similar to left-aligned text
 	AlignMiddle             // similar to center-aligned text
@@ -108,24 +111,66 @@ type Object interface {
 type Box interface {
 	Object
 
+	// Window returns the Window this Box is a part of.
 	Window         () Window
+	// Bounds returns the outer bounding rectangle of the Box relative to
+	// the Window.
 	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
+	// 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:
+	//   - The size as set by SetMinimumSize
+	//   - 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
+	// 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)
+	// 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)
-	SetMinimumSize (int, int)
+	// 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)
 
+	// 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)
+	// 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.
 	SetDNDAccept (...data.Mime)
+	// 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)
+	// 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
+	// Modifiers returns which modifier keys on the keyboard are currently
+	// being held down.
 	Modifiers     () input.Modifiers
+	// MousePosition returns the position of the mouse pointer relative to
+	// the Window.
 	MousePosition () image.Point
 
+	// These are event subscription functions that allow callbacks to be
+	// connected to particular events. Multiple callbacks may be connected
+	// to the same event at once. Callbacks can be removed by closing the
+	// returned cookie.
 	OnFocusEnter  (func ()) event.Cookie
 	OnFocusLeave  (func ()) event.Cookie
 	OnDNDEnter    (func ()) event.Cookie
@@ -144,7 +189,13 @@ type Box interface {
 // CanvasBox is a box that can be drawn to.
 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)
+
+	// Invalidate causes the Box's area to be redrawn at the end of the
+	// event cycle, even if it wouldn't be otherwise.
 	Invalidate ()
 }
 
@@ -152,58 +203,151 @@ type CanvasBox interface {
 // is to be embedded into TextBox and ContainerBox.
 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)
+	// SetAlign sets how the Box's content is distributed horizontally and
+	// vertically.
+	SetAlign              (x, y Align)
+	// ContentBounds returns the bounds of the inner content of the Box
+	// relative to the window.
 	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
 }
 
 // TextBox is a box that contains text content.
 type TextBox interface {
 	ContentBox
-	SetTextColor (color.Color)
-	SetFace      (font.Face)
-	SetHAlign    (Align)
-	SetVAlign    (Align)
+
+	// SetText sets the text content of the Box.
+	SetText       (string)
+	// SetTextColor sets the text color.
+	SetTextColor  (color.Color)
+	// SetFace sets the font face text is rendered in.
+	SetFace       (font.Face)
+	// SetWrap sets whether or not the text wraps.
+	SetWrap       (bool)
+
+	// SetSelectable sets whether or not the text content can be
+	// highlighted/selected.
+	SetSelectable (bool)
+	// Select sets the text cursor or selection.
+	Select        (text.Dot)
+	// Dot returns the text cursor or selection.
+	Dot           () text.Dot
+	// OnDotChange specifies a function to be called when the text cursor or
+	// selection changes.
+	OnDotChange   (func ()) event.Cookie
 }
 
-// ContentBox is a box that can contain child objects. It arranges them
+// ContentBox is a box that can contain child Objects. It arranges them
 // according to a layout rule.
 type ContainerBox interface {
 	ContentBox
-	SetGap    (Gap)
-	Add       (Object)
-	Delete    (Object)
-	Insert    (child Object, before Object)
-	Clear     ()
-	Length    () int
-	At        (int) Object
-	SetLayout (Layout)
+
+	// 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)
+	// 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)
+	// Clear removes all child Objects.
+	Clear              ()
+	// Length returns the amount of child objects.
+	Length             () int
+	// At returns the child Object at the specified index.
+	At                 (int) Object
+	// SetLayout sets the layout of this Box. Child Objects will be
+	// positioned according to it.
+	SetLayout          (Layout)
 }
 
-// Layout can be given to a ContainerBox to arrange child objects.
+// LayoutHints are passed to a layout to tell it how to arrange child boxes.
+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
+	// 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
+	// Gap controls the amount of horizontal and vertical spacing in-between
+	// child Boxes.
+	Gap image.Point
+}
+
+// A Layout can be given to a ContainerBox to arrange child objects.
 type Layout interface {
-	Arrange (image.Rectangle, Gap, []Box)
+	// MinimumSize returns the minimum width and height of
+	// 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)
 }
 
 // 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)
+	// SetTitle sets the title of the window.
 	SetTitle (string)
-	SetIcon  (sizes []image.Image)
-	NewMenu  (image.Rectangle) (Window, error)
-	NewModal (image.Rectangle) (Window, error)
+	// SetIcon sets the icon of the window. When multiple icon sizes are
+	// provided, the best fitting one is chosen for display.
+	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)
+	// 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)
+	// 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)
+	// 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     ()
+	// Close closes the window.
 	Close    ()
+	// OnClose specifies a function to be called when the window is closed.
 	OnClose  (func ()) event.Cookie
 }
 
 // MainWindow is a top-level operating system window.
 type MainWindow interface {
 	Window
+
+	// NewChild creates a new window that is semantically a child of this
+	// window. It does not actually reside within this window, but it may be
+	// linked to it via some other means. This is intended for things like
+	// toolboxes and tear-off menus.
 	NewChild (image.Rectangle) (Window, error)
 }

text/text.go

@@ -0,0 +1,248 @@
+package text
+
+import "unicode"
+
+// Dot represents a cursor or text selection. It has a start and end position,
+// referring to where the user began and ended the selection respectively.
+type Dot struct { Start, End int }
+
+// EmptyDot returns a zero-width dot at the specified position.
+func EmptyDot (position int) Dot {
+	return Dot { position, position }
+}
+
+// Canon places the lesser value at the start, and the greater value at the end.
+// Note that a canonized dot does not in all cases correspond directly to the
+// original, because there is a semantic value to the start and end positions.
+func (dot Dot) Canon () Dot {
+	if dot.Start > dot.End {
+		return Dot { dot.End, dot.Start }
+	} else {
+		return dot
+	}
+}
+
+// Empty returns whether or not the 
+func (dot Dot) Empty () bool {
+	return dot.Start == dot.End
+}
+
+// Add shifts the dot to the right by the specified amount.
+func (dot Dot) Add (delta int) Dot {
+	return Dot {
+		dot.Start + delta,
+		dot.End   + delta,
+	}
+}
+
+// Sub shifts the dot to the left by the specified amount.
+func (dot Dot) Sub (delta int) Dot {
+	return Dot {
+		dot.Start - delta,
+		dot.End   - delta,
+	}
+}
+
+// Constrain constrains the dot's start and end from zero to length (inclusive).
+func (dot Dot) Constrain (length int) Dot {
+	if dot.Start < 0      { dot.Start = 0      }
+	if dot.Start > length { dot.Start = length }
+	if dot.End   < 0      { dot.End   = 0      }
+	if dot.End   > length { dot.End   = length }
+	return dot
+}
+
+// Width returns how many runes the dot spans.
+func (dot Dot) Width () int {
+	dot = dot.Canon()
+	return dot.End - dot.Start
+}
+
+// Slice returns the subset of text that the dot covers.
+func (dot Dot) Slice (text []rune) []rune {
+	dot = dot.Canon().Constrain(len(text))
+	return text[dot.Start:dot.End]
+}
+
+// WordToLeft returns how far away to the left the next word boundary is from a
+// given position.
+func WordToLeft (text []rune, position int) (length int) {
+	if position < 1 { return }
+	if position > len(text) { position = len(text) }
+
+	index := position - 1
+	for index >= 0 && unicode.IsSpace(text[index]) {
+		length ++
+		index --
+	}
+	for index >= 0 && !unicode.IsSpace(text[index]) {
+		length ++
+		index --
+	}
+	return
+}
+
+// WordToRight returns how far away to the right the next word boundary is from
+// a given position.
+func WordToRight (text []rune, position int) (length int) {
+	if position < 0 { return }
+	if position > len(text) { position = len(text) }
+
+	index := position
+	for index < len(text) && unicode.IsSpace(text[index]) {
+		length ++
+		index ++
+	}
+	for index < len(text) && !unicode.IsSpace(text[index]) {
+		length ++
+		index ++
+	}
+	return
+}
+
+// WordAround returns a dot that surrounds the word at the specified position.
+func WordAround (text []rune, position int) (around Dot) {
+	return Dot {
+		position - WordToLeft(text, position),
+		position + WordToRight(text, position),
+	}
+}
+
+// Backspace deletes the rune to the left of the dot. If word is true, it
+// deletes up until the next word boundary on the left. If the dot is non-empty,
+// it deletes the text inside of the dot.
+func Backspace (text []rune, dot Dot, word bool) (result []rune, moved Dot) {
+	dot = dot.Constrain(len(text))
+	if dot.Empty() {
+		distance := 1
+		if word {
+			distance = WordToLeft(text, dot.End)
+		}
+		result = append (
+			result,
+			text[:dot.Sub(distance).Constrain(len(text)).End]...)
+		result = append(result, text[dot.End:]...)
+		moved = EmptyDot(dot.Sub(distance).Start)
+		return
+	} else {
+		return Delete(text, dot, word)
+	}
+}
+
+// Delete deletes the rune to the right of the dot. If word is true, it deletes
+// up until the next word boundary on the right. If the dot is non-empty, it
+// deletes the text inside of the dot.
+func Delete (text []rune, dot Dot, word bool) (result []rune, moved Dot) {
+	dot = dot.Constrain(len(text))
+	if dot.Empty() {
+		distance := 1
+		if word {
+			distance = WordToRight(text, dot.End)
+		}
+		result = append(result, text[:dot.End]...)
+		result = append (
+			result,
+			text[dot.Add(distance).Constrain(len(text)).End:]...)
+		moved = dot
+		return	
+	} else {
+		dot = dot.Canon()
+		result = append(result, text[:dot.Start]...)
+		result = append(result, text[dot.End:]...)
+		moved = EmptyDot(dot.Start)
+		return
+	}
+}
+
+// Lift removes the section of text inside of the dot, and returns a copy of it.
+func Lift (text []rune, dot Dot) (result []rune, moved Dot, lifted []rune) {
+	dot = dot.Constrain(len(text))
+	if dot.Empty() {
+		moved = dot
+		return
+	}
+
+	dot = dot.Canon()
+	lifted = make([]rune, dot.Width())
+	copy(lifted, dot.Slice(text))
+	result = append(result, text[:dot.Start]...)
+	result = append(result, text[dot.End:]...)
+	moved = EmptyDot(dot.Start)
+	return
+}
+
+// Type inserts one of more runes into the text at the dot position. If the dot
+// is non-empty, it replaces the text inside of the dot with the new runes.
+func Type (text []rune, dot Dot, characters ...rune) (result []rune, moved Dot) {
+	dot = dot.Constrain(len(text))
+	if dot.Empty() {
+		result = append(result, text[:dot.End]...)
+		result = append(result, characters...)
+		if dot.End < len(text) {
+			result = append(result, text[dot.End:]...)
+		}
+		moved = EmptyDot(dot.Add(len(characters)).End)
+		return
+	} else {
+		dot = dot.Canon()
+		result = append(result, text[:dot.Start]...)
+		result = append(result, characters...)
+		result = append(result, text[dot.End:]...)
+		moved = EmptyDot(dot.Add(len(characters)).Start)
+		return
+	}
+}
+
+// MoveLeft moves the dot left one rune. If word is true, it moves the dot to
+// the next word boundary on the left.
+func MoveLeft (text []rune, dot Dot, word bool) (moved Dot) {
+	dot = dot.Canon().Constrain(len(text))
+	distance := 0
+	if dot.Empty() {
+		distance = 1
+	}
+	if word {
+		distance = WordToLeft(text, dot.Start)
+	}
+	moved = EmptyDot(dot.Sub(distance).Start)
+	return
+}
+
+// MoveRight moves the dot right one rune. If word is true, it moves the dot to
+// the next word boundary on the right.
+func MoveRight (text []rune, dot Dot, word bool) (moved Dot) {
+	dot = dot.Canon().Constrain(len(text))
+	distance := 0
+	if dot.Empty() {
+		distance = 1
+	}
+	if word {
+		distance = WordToRight(text, dot.End)
+	}
+	moved = EmptyDot(dot.Add(distance).End)
+	return
+}
+
+// SelectLeft moves the end of the dot left one rune. If word is true, it moves
+// the end of the dot to the next word boundary on the left.
+func SelectLeft (text []rune, dot Dot, word bool) (moved Dot) {
+	dot = dot.Constrain(len(text))
+	distance := 1
+	if word {
+		distance = WordToLeft(text, dot.End)
+	}
+	dot.End -= distance
+	return dot
+}
+
+// SelectRight moves the end of the dot right one rune. If word is true, it
+// moves the end of the dot to the next word boundary on the right.
+func SelectRight (text []rune, dot Dot, word bool) (moved Dot) {
+	dot = dot.Constrain(len(text))
+	distance := 1
+	if word {
+		distance = WordToRight(text, dot.End)
+	}
+	dot.End += distance
+	return dot
+}

tomo.go

@@ -1,8 +1,10 @@
 package tomo
 
+import "sync"
 import "image"
 import "errors"
 
+var backendLock sync.Mutex
 var backend Backend
 
 // Run initializes a backend, runs the specified callback function, and runs the
@@ -17,7 +19,10 @@ func Run (callback func ()) error {
 
 	back, err := Initialize()
 	if err != nil { return err }
+	
+	backendLock.Lock()
 	backend = back
+	backendLock.Unlock()
 
 	callback()
 	return backend.Run()
@@ -32,29 +37,44 @@ func assertBackend () {
 func Stop () {
 	assertBackend()
 	backend.Stop()
+	
+	backendLock.Lock()
 	backend = nil
+	backendLock.Unlock()
 }
 
+// Do performs a callback function in the event loop thread as soon as possible.
+func Do (callback func ()) {
+	backendLock.Lock()
+	if backend != nil { backend.Do(callback) }
+	backendLock.Unlock()
+}
+
+// NewWindow creates and returns a window within the specified bounds on screen.
 func NewWindow (bounds image.Rectangle) (MainWindow, error) {
 	assertBackend()
 	return backend.NewWindow(bounds)
 }
 
+// NewBox creates and returns a basic Box.
 func NewBox () Box {
 	assertBackend()
 	return backend.NewBox()
 }
 
+// NewTextBox creates and returns a Box that can display text.
 func NewTextBox () TextBox {
 	assertBackend()
 	return backend.NewTextBox()
 }
 
+// NewCanvasBox creates and returns a Box that can display custom graphics.
 func NewCanvasBox () CanvasBox {
 	assertBackend()
 	return backend.NewCanvasBox()
 }
 
+// NewContainerBox creates and returns a Box that can contain other boxes.
 func NewContainerBox () ContainerBox {
 	assertBackend()
 	return backend.NewContainerBox()