Changed the way minimum sizes are calculated

Boxes that need their minimum size to be updated now use a map like
for layout and drawing. Size set with MinimumSize is now treated as
separate from the content size and the larger size is used.

backend.go

@@ -48,9 +48,7 @@ func (backend *Backend) Run () error {
 		case <- pingQuit:
 			return nil // FIXME: if we exited due to an error say so
 		}
-		for _, window := range backend.windows {
-			window.afterEvent()
-		}
+		backend.afterEvent()
 	}
 }
 
@@ -78,3 +76,9 @@ func (backend *Backend) Do (callback func ()) {
 func (backend *Backend) assert () {
 	if backend == nil { panic("nil backend") }
 }
+
+func (backend *Backend) afterEvent () {
+	for _, window := range backend.windows {
+		window.afterEvent()
+	}
+}

box.go

@@ -13,8 +13,12 @@ type box struct {
 	parent   parent
 	outer    anyBox
 
-	bounds  image.Rectangle
-	minSize image.Point
+	bounds      image.Rectangle
+	minSize     image.Point
+	userMinSize image.Point
+	
+	minSizeQueued bool
+	focusQueued   *bool
 
 	padding tomo.Inset
 	border  []tomo.Border
@@ -45,13 +49,23 @@ type box struct {
 	}
 }
 
-func (backend *Backend) NewBox() tomo.Box {
+func (backend *Backend) newBox (outer anyBox) *box {
 	box := &box {
 		backend: backend,
 		color:   color.White,
+		outer:   outer,
+		drawer:  outer,
 	}
-	box.drawer = box
-	box.outer  = box
+	if outer == nil {
+		box.drawer = box
+		box.outer  = box
+	}
+	box.invalidateMinimum()
+	return box
+}
+
+func (backend *Backend) NewBox() tomo.Box {
+	box := backend.newBox(nil)
 	return box
 }
 
@@ -105,23 +119,20 @@ func (this *box) SetColor (c color.Color) {
 func (this *box) SetBorder (border ...tomo.Border) {
 	this.border = border
 	this.invalidateLayout()
-	this.recalculateMinimumSize()
+	this.invalidateMinimum()
 }
 
 func (this *box) SetMinimumSize (size image.Point) {
-	if this.minSize == size { return }
-	this.minSize = size
-	
-	if this.parent != nil {
-		this.parent.notifyMinimumSizeChange(this)
-	}
+	if this.userMinSize == size { return }
+	this.userMinSize = size
+	this.invalidateMinimum()
 }
 
 func (this *box) SetPadding (padding tomo.Inset) {
 	if this.padding == padding { return }
 	this.padding = padding
 	this.invalidateLayout()
-	this.recalculateMinimumSize()
+	this.invalidateMinimum()
 }
 
 func (this *box) SetDNDData (dat data.Data) {
@@ -133,9 +144,11 @@ func (this *box) SetDNDAccept (types ...data.Mime) {
 }
 
 func (this *box) SetFocused (focused bool) {
-	if this.parent == nil { return }
-	window := this.parent.window()
-	if window == nil { return }
+	if this.parent == nil || this.parent.window () == nil {
+		focusedCopy := focused
+		this.focusQueued = &focusedCopy
+		return
+	}
 	if !this.focusable { return }
 	
 	if this.Focused () && !focused {
@@ -251,6 +264,30 @@ func (this *box) drawBorders (can canvas.Canvas) {
 	}
 }
 
+func (this *box) contentMinimum () image.Point {
+	var minimum image.Point
+	minimum.X += this.padding.Horizontal()
+	minimum.Y += this.padding.Vertical()
+	borderSum := this.borderSum()
+	minimum.X += borderSum.Horizontal()
+	minimum.Y += borderSum.Vertical()
+	return minimum
+}
+
+func (this *box) doMinimumSize () {
+	this.minSize = this.outer.contentMinimum()
+	if this.minSize.X < this.userMinSize.X {
+		this.minSize.X = this.userMinSize.X
+	}
+	if this.minSize.Y < this.userMinSize.Y {
+		this.minSize.Y = this.userMinSize.Y
+	}
+	
+	if this.parent != nil {
+		this.parent.notifyMinimumSizeChange(this)
+	}
+}
+
 func (this *box) doDraw () {
 	if this.canvas == nil { return }
 	if this.drawer != nil {
@@ -273,6 +310,17 @@ func (this *box) setParent (parent parent) {
 	this.parent = parent
 }
 
+func (this *box) flushActionQueue () {
+	if this.parent == nil || this.parent.window() == nil { return }
+
+	if this.minSizeQueued {
+		this.invalidateMinimum()
+	}
+	if this.focusQueued != nil {
+		this.SetFocused(*this.focusQueued)
+	}
+}
+
 func (this *box) recursiveRedo () {
 	this.doLayout()
 	this.doDraw()
@@ -288,10 +336,12 @@ func (this *box) invalidateDraw () {
 	this.parent.window().invalidateDraw(this.outer)
 }
 
-func (this *box) recalculateMinimumSize () {
-	if this.outer != anyBox(this) {
-		this.outer.recalculateMinimumSize()
+func (this *box) invalidateMinimum () {
+	if this.parent == nil || this.parent.window() == nil {
+		this.minSizeQueued = true
+		return
 	}
+	this.parent.window().invalidateMinimum(this.outer)
 }
 
 func (this *box) canBeFocused () bool {

canvasbox.go

@@ -8,11 +8,9 @@ type canvasBox struct {
 }
 
 func (backend *Backend) NewCanvasBox () tomo.CanvasBox {
-	box := &canvasBox {
-		box: backend.NewBox().(*box),
-	}
-	box.outer = box
-	return box
+	this    := &canvasBox { }
+	this.box = backend.newBox(this)
+	return this
 }
 
 func (this *canvasBox) Box () tomo.Box {

containerbox.go

@@ -24,13 +24,9 @@ type containerBox struct {
 }
 
 func (backend *Backend) NewContainerBox() tomo.ContainerBox {
-	box := &containerBox {
-		box:             backend.NewBox().(*box),
-		propagateEvents: true,
-	}
-	box.drawer = box
-	box.outer  = box
-	return box
+	this    := &containerBox { propagateEvents: true }
+	this.box = backend.newBox(this)
+	return this
 }
 
 func (this *containerBox) SetOverflow (horizontal, vertical bool) {
@@ -69,7 +65,7 @@ func (this *containerBox) SetGap (gap image.Point) {
 	if this.gap == gap { return }
 	this.gap = gap
 	this.invalidateLayout()
-	this.recalculateMinimumSize()
+	this.invalidateMinimum()
 }
 
 func (this *containerBox) Add (child tomo.Object) {
@@ -77,9 +73,10 @@ func (this *containerBox) Add (child tomo.Object) {
 	if indexOf(this.children, tomo.Box(box)) > -1 { return }
 	
 	box.setParent(this)
+	box.flushActionQueue()
 	this.children = append(this.children, box)
 	this.invalidateLayout()
-	this.recalculateMinimumSize()
+	this.invalidateMinimum()
 }
 
 func (this *containerBox) Delete (child tomo.Object) {
@@ -90,7 +87,7 @@ func (this *containerBox) Delete (child tomo.Object) {
 	box.setParent(nil)
 	this.children = remove(this.children, index)
 	this.invalidateLayout()
-	this.recalculateMinimumSize()
+	this.invalidateMinimum()
 }
 
 func (this *containerBox) Insert (child, before tomo.Object) {
@@ -104,7 +101,7 @@ func (this *containerBox) Insert (child, before tomo.Object) {
 	box.setParent(this)
 	this.children = insert(this.children, index, tomo.Box(box))
 	this.invalidateLayout()
-	this.recalculateMinimumSize()
+	this.invalidateMinimum()
 }
 
 func (this *containerBox) Clear () {
@@ -113,7 +110,7 @@ func (this *containerBox) Clear () {
 	}
 	this.children = nil
 	this.invalidateLayout()
-	this.recalculateMinimumSize()
+	this.invalidateMinimum()
 }
 
 func (this *containerBox) Length () int {
@@ -130,7 +127,7 @@ func (this *containerBox) At (index int) tomo.Object {
 func (this *containerBox) SetLayout (layout tomo.Layout) {
 	this.layout = layout
 	this.invalidateLayout()
-	this.recalculateMinimumSize()
+	this.invalidateMinimum()
 }
 
 func (this *containerBox) Draw (can canvas.Canvas) {
@@ -148,6 +145,13 @@ func (this *containerBox) Draw (can canvas.Canvas) {
 	}
 }
 
+func (this *containerBox) flushActionQueue () {
+	for _, box := range this.children {
+		box.(anyBox).flushActionQueue()
+	}
+	this.box.flushActionQueue()
+}
+
 func (this *containerBox) window () *window {
 	if this.parent == nil { return nil }
 	return this.parent.window()
@@ -158,8 +162,7 @@ func (this *containerBox) canvas () canvas.Canvas {
 }
 
 func (this *containerBox) notifyMinimumSizeChange (child anyBox) {
-	this.recalculateMinimumSize()
-
+	this.invalidateMinimum()
 	size   := child.MinimumSize()
 	bounds := child.Bounds()
 	if bounds.Dx() < size.X || bounds.Dy() < size.Y {
@@ -179,18 +182,15 @@ func (this *containerBox) layoutHints () tomo.LayoutHints {
 	}
 }
 
-func (this *containerBox) recalculateMinimumSize () {
-	if this.layout == nil {
-		this.SetMinimumSize(image.Point { })
-		return
+func (this *containerBox) contentMinimum () image.Point {
+	minimum := this.box.contentMinimum()
+	if this.layout != nil {
+		minimum = minimum.Add (
+			this.layout.MinimumSize (
+				this.layoutHints(),
+				this.children))
 	}
-	minimum := this.layout.MinimumSize(this.layoutHints(), this.children)
-	minimum.X += this.padding.Horizontal()
-	minimum.Y += this.padding.Vertical()
-	borderSum := this.borderSum()
-	minimum.X += borderSum.Horizontal()
-	minimum.Y += borderSum.Vertical()
-	this.SetMinimumSize(minimum)
+	return minimum
 }
 
 func (this *containerBox) doLayout () {

system.go

@@ -40,13 +40,17 @@ type parent interface {
 
 type anyBox interface {
 	tomo.Box
-	doDraw        ()
-	doLayout      ()
-	setParent     (parent)
-	recursiveRedo ()
-	canBeFocused  () bool
-	boxUnder      (image.Point) anyBox
-	recalculateMinimumSize ()
+	canvas.Drawer
+	
+	doDraw           ()
+	doLayout         ()
+	doMinimumSize    ()
+	contentMinimum   () image.Point
+	setParent        (parent)
+	flushActionQueue ()
+	recursiveRedo    ()
+	canBeFocused     () bool
+	boxUnder         (image.Point) anyBox
 
 	propagate    (func (anyBox) bool) bool
 	propagateAlt (func (anyBox) bool) bool
@@ -83,10 +87,11 @@ func (window *window) SetRoot (root tomo.Object) {
 	} else {
 		box := assertAnyBox(root.GetBox())
 		box.setParent(window)
+		box.flushActionQueue()
 		window.invalidateLayout(box)
 		window.root = box
 	}
-	window.recalculateMinimumSize()
+	window.minimumClean = false
 }
 
 func (window *window) window () *window {
@@ -98,7 +103,11 @@ func (window *window) canvas () canvas.Canvas {
 }
 
 func (window *window) notifyMinimumSizeChange (anyBox) {
-	window.recalculateMinimumSize()
+	window.minimumClean = false
+}
+
+func (window *window) invalidateMinimum (box anyBox) {
+	window.needMinimum.Add(box)
 }
 
 func (window *window) invalidateDraw (box anyBox) {
@@ -106,8 +115,6 @@ func (window *window) invalidateDraw (box anyBox) {
 }
 
 func (window *window) invalidateLayout (box anyBox) {
-	// TODO: use a priority queue for this and have the value be the amount
-	// of parents a box has
 	window.needLayout.Add(box)
 	window.invalidateDraw(box)
 }
@@ -214,6 +221,12 @@ func (window *window) afterEvent () {
 		return
 	}
 
+	for len(window.needMinimum) > 0 {
+		window.needMinimum.Pop().doMinimumSize()
+	}
+	if !window.minimumClean {
+		window.doMinimumSize()
+	}
 	for len(window.needLayout) > 0 {
 		window.needLayout.Pop().doLayout()
 	}

textbox.go

@@ -39,14 +39,12 @@ type textBox struct {
 }
 
 func (backend *Backend) NewTextBox() tomo.TextBox {
-	box := &textBox {
-		box:       backend.NewBox().(*box),
+	this := &textBox {
 		textColor: color.Black,
 		dotColor:  color.RGBA { B: 255, G: 255, A: 255 },
 	}
-	box.box.drawer = box
-	box.outer  = box
-	return box
+	this.box = backend.newBox(this)
+	return this
 }
 
 func (this *textBox) SetOverflow (horizontal, vertical bool) {
@@ -74,7 +72,7 @@ func (this *textBox) SetText (text string) {
 	if this.text == text { return }
 	this.text = text
 	this.drawer.SetText([]rune(text))
-	this.recalculateMinimumSize()
+	this.invalidateMinimum()
 	this.invalidateLayout()
 }
 
@@ -88,14 +86,14 @@ func (this *textBox) SetFace (face font.Face) {
 	if this.face == face { return }
 	this.face = face
 	this.drawer.SetFace(face)
-	this.recalculateMinimumSize()
+	this.invalidateMinimum()
 	this.invalidateLayout()
 }
 
 func (this *textBox) SetWrap (wrap bool) {
 	if this.wrap == wrap { return }
 	this.drawer.SetWrap(wrap)
-	this.recalculateMinimumSize()
+	this.invalidateMinimum()
 	this.invalidateLayout()
 }
 
@@ -271,7 +269,7 @@ func (this *textBox) normalizedLayoutBoundsSpace () image.Rectangle {
 	return bounds.Sub(bounds.Min)
 }
 
-func (this *textBox) recalculateMinimumSize () {
+func (this *textBox) contentMinimum () image.Point {
 	minimum := image.Pt (
 		this.drawer.Em().Round(),
 		this.drawer.LineHeight().Round())
@@ -283,13 +281,8 @@ func (this *textBox) recalculateMinimumSize () {
 	if !this.vOverflow {
 		 minimum.Y = textSize.Y
 	}
-	
-	minimum.X += this.padding.Horizontal()
-	minimum.Y += this.padding.Vertical()
-	borderSum := this.borderSum()
-	minimum.X += borderSum.Horizontal()
-	minimum.Y += borderSum.Vertical()
-	this.SetMinimumSize(minimum)
+
+	return minimum.Add(this.box.contentMinimum())
 }
 
 func (this *textBox) doLayout () {

window.go

@@ -46,9 +46,17 @@ type window struct {
 	focused anyBox
 	hovered anyBox
 
-	needDraw   boxSet
-	needLayout boxSet
-	needRedo   bool
+	// TODO: needMinimum and needLayout should be priority queues. for the
+	// minimums, we need to start at the deeper parts of the layout tree and
+	// go upward towards the top. for the layouts, we need to start at the
+	// top of the layout tree and progressively go deeper. this will
+	// eliminate redundant layout calculations.
+
+	needMinimum  boxSet
+	needLayout   boxSet
+	needDraw     boxSet
+	needRedo     bool
+	minimumClean bool
 }
 
 func (backend *Backend) NewWindow (
@@ -130,7 +138,7 @@ func (backend *Backend) newWindow (
 		// Connect(backend.x, window.xWindow.Id)
 	
 	window.metrics.bounds = bounds
-	window.setMinimumSize(image.Pt(8, 8))
+	window.doMinimumSize()
 
 	backend.windows[window.xWindow.Id] = window
 
@@ -353,15 +361,14 @@ func (window *window) pushRegion (region image.Rectangle) {
 	subCanvas.(*xcanvas.Canvas).Push(window.xWindow.Id)
 }
 
-func (window *window) recalculateMinimumSize () {
-	rootMinimum := image.Point { }
-	if window.root != nil {
-		rootMinimum = window.root.MinimumSize()
-	}
-	window.setMinimumSize(rootMinimum)
-}
+func (window *window) doMinimumSize () {
+	window.minimumClean = true
 
-func (window *window) setMinimumSize (size image.Point) {
+	size := image.Point { }
+	if window.root != nil {
+		size = window.root.MinimumSize()
+	}
+	
 	if size.X < 8 { size.X = 8 }
 	if size.Y < 8 { size.Y = 8 }
 	icccm.WmNormalHintsSet (