Remedy #1

redundantly

box.go

@@ -117,14 +117,34 @@ func (this *box) SetColor (c color.Color) {
 }
 
 func (this *box) SetTexture (texture canvas.Texture) {
+	if this.texture == texture { return }
 	this.texture = xcanvas.AssertTexture(texture)
 	this.invalidateDraw()
 }
 
-func (this *box) SetBorder (border ...tomo.Border) {
-	this.border = border
-	this.invalidateLayout()
-	this.invalidateMinimum()
+func (this *box) SetBorder (borders ...tomo.Border) {
+	previousBorderSum := this.borderSum()
+	previousBorders   := this.border
+	this.border = borders
+
+	// only invalidate the layout if the border is sized differently
+	if this.borderSum() != previousBorderSum {
+		this.invalidateLayout()
+		this.invalidateMinimum()
+		return
+	}
+
+	// if the border takes up the same amount of space, only invalidate the
+	// drawing if it looks different
+	for index, newBorder := range this.border {
+		different :=
+			index >= len(previousBorders) ||
+			newBorder != previousBorders[index]
+		if different {
+			this.invalidateDraw()
+			return
+		}
+	}
 }
 
 func (this *box) SetMinimumSize (size image.Point) {
@@ -285,7 +305,7 @@ func (this *box) Draw (can canvas.Canvas) {
 	if this.transparent() && this.parent != nil {
 		this.parent.drawBackgroundPart(can)
 	}
-	pen.Rectangle(can.Bounds())
+	pen.Rectangle(this.Bounds())
 }
 
 func (this *box) drawBorders (can canvas.Canvas) {
@@ -356,7 +376,11 @@ func (this *box) doMinimumSize () {
 	}
 }
 
+// var drawcnt int
 func (this *box) doDraw () {
+	// println("DRAW", drawcnt)
+	// drawcnt ++
+	
 	if this.canvas == nil { return }
 	if this.drawer != nil {
 		this.drawBorders(this.canvas)
@@ -364,7 +388,11 @@ func (this *box) doDraw () {
 	}
 }
 
+// var laycnt int
 func (this *box) doLayout () {
+	// println("LAYOUT", laycnt)
+	// laycnt ++
+	
 	this.innerClippingBounds = this.borderSum().Apply(this.bounds)
 	if this.parent == nil { this.canvas = nil; return  }
 	parentCanvas := this.parent.canvas()

containerbox.go

@@ -31,11 +31,13 @@ func (backend *Backend) NewContainerBox() tomo.ContainerBox {
 }
 
 func (this *containerBox) SetColor (c color.Color) {
+	if this.color == c { return }
 	this.box.SetColor(c)
 	this.invalidateTransparentChildren()
 }
 
 func (this *containerBox) SetTexture (texture canvas.Texture) {
+	if this.texture == texture { return }
 	this.box.SetTexture(texture)
 	this.invalidateTransparentChildren()
 }
@@ -59,7 +61,7 @@ func (this *containerBox) ContentBounds () image.Rectangle {
 }
 
 func (this *containerBox) ScrollTo (point image.Point) {
-	// TODO: constrain scroll
+	if this.scroll == point { return }
 	this.scroll = point
 	this.invalidateLayout()
 }
@@ -68,19 +70,19 @@ func (this *containerBox) OnContentBoundsChange (callback func()) event.Cookie {
 	return this.on.contentBoundsChange.Connect(callback)
 }
 
-func (this *containerBox)  CaptureDND (capture bool) {
+func (this *containerBox) CaptureDND (capture bool) {
 	this.capture[eventCategoryDND] = capture
 }
 
-func (this *containerBox)  CaptureMouse (capture bool) {
+func (this *containerBox) CaptureMouse (capture bool) {
 	this.capture[eventCategoryMouse] = capture
 }
 
-func (this *containerBox)  CaptureScroll (capture bool) {
+func (this *containerBox) CaptureScroll (capture bool) {
 	this.capture[eventCategoryScroll] = capture
 }
 
-func (this *containerBox)  CaptureKeyboard (capture bool) {
+func (this *containerBox) CaptureKeyboard (capture bool) {
 	this.capture[eventCategoryKeyboard] = capture
 }
 
@@ -226,9 +228,7 @@ func (this *containerBox) notifyMinimumSizeChange (child anyBox) {
 }
 
 func (this *containerBox) layoutHints () tomo.LayoutHints {
-	innerBounds := this.InnerBounds().Sub(this.scroll)
 	return tomo.LayoutHints {
-		Bounds:    innerBounds,
 		OverflowX: this.hOverflow,
 		OverflowY: this.vOverflow,
 		AlignX:    this.hAlign,
@@ -240,10 +240,12 @@ func (this *containerBox) layoutHints () tomo.LayoutHints {
 func (this *containerBox) contentMinimum () image.Point {
 	minimum := this.box.contentMinimum()
 	if this.layout != nil {
-		minimum = minimum.Add (
-			this.layout.MinimumSize (
-				this.layoutHints(),
-				this.children))
+		layoutMinimum := this.layout.MinimumSize (
+			this.layoutHints(),
+			this.children)
+		if this.hOverflow { layoutMinimum.X = 0 }
+		if this.vOverflow { layoutMinimum.Y = 0 }
+		minimum = minimum.Add(layoutMinimum)
 	}
 	return minimum
 }
@@ -251,14 +253,73 @@ func (this *containerBox) contentMinimum () image.Point {
 func (this *containerBox) doLayout () {
 	this.box.doLayout()
 	previousContentBounds := this.contentBounds
+
+	// by default, use innerBounds (translated to 0, 0) for contentBounds.
+	// if a direction overflows, use the layout's minimum size for it.
+	var minimum image.Point
 	if this.layout != nil {
-		this.layout.Arrange(this.layoutHints(), this.children)
+		minimum = this.layout.MinimumSize (
+			this.layoutHints(),
+			this.children)
 	}
+	innerBounds := this.InnerBounds()
+	this.contentBounds = innerBounds.Sub(innerBounds.Min)
+	if this.hOverflow { this.contentBounds.Max.X = this.contentBounds.Min.X + minimum.X }
+	if this.vOverflow { this.contentBounds.Max.Y = this.contentBounds.Min.Y + minimum.Y }
+	
+	// arrange children
+	if this.layout != nil {
+		layoutHints := this.layoutHints()
+		layoutHints.Bounds = this.contentBounds
+		this.layout.Arrange(layoutHints, this.children)
+	}
+
+	// build an accurate contentBounds by unioning the bounds of all child
+	// boxes
+	this.contentBounds = image.Rectangle { }
+	for _, box := range this.children {
+		bounds := box.Bounds()
+		this.contentBounds = this.contentBounds.Union(bounds)
+	}
+
+	// constrain the scroll
+	this.constrainScroll()
+
+	// offset children and contentBounds by scroll
+	for _, box := range this.children {
+		box.SetBounds(box.Bounds().Add(this.scroll).Add(innerBounds.Min))
+	}
+	this.contentBounds = this.contentBounds.Add(this.scroll)
+	
 	if previousContentBounds != this.contentBounds {
 		this.on.contentBoundsChange.Broadcast()
 	}
 }
 
+func (this *containerBox) constrainScroll () {
+	innerBounds := this.InnerBounds()
+	width  := this.contentBounds.Dx()
+	height := this.contentBounds.Dy()
+
+	// X
+	if width <= innerBounds.Dx() {
+		this.scroll.X = 0
+	} else if this.scroll.X > 0 {
+		this.scroll.X = 0
+	} else if this.scroll.X < innerBounds.Dx() - width  {
+		this.scroll.X =  innerBounds.Dx() - width
+	}
+
+	// Y
+	if height <= innerBounds.Dy() {
+		this.scroll.Y = 0
+	} else if this.scroll.Y > 0 {
+		this.scroll.Y = 0
+	} else if this.scroll.Y < innerBounds.Dy() - height {
+		this.scroll.Y = innerBounds.Dy() - height
+	}
+}
+
 func (this *containerBox) recursiveRedo () {
 	this.doLayout()
 	this.doDraw()
@@ -268,6 +329,8 @@ func (this *containerBox) recursiveRedo () {
 }
 
 func (this *containerBox) boxUnder (point image.Point, category eventCategory) anyBox {
+	if !point.In(this.bounds) { return nil }
+
 	if !this.capture[category] {
 		for _, box := range this.children {
 			candidate := box.(anyBox).boxUnder(point, category)
@@ -275,7 +338,7 @@ func (this *containerBox) boxUnder (point image.Point, category eventCategory) a
 		}
 	}
 
-	return this.box.boxUnder(point, category)
+	return this
 }
 
 func (this *containerBox) propagate (callback func (anyBox) bool) bool {

event.go

@@ -161,16 +161,17 @@ func (window *window) handleConfigureNotify (
 	if window.root == nil { return }
 	
 	configureEvent := *event.ConfigureNotifyEvent
+	configureEvent = window.compressConfigureNotify(configureEvent)
 	
-	newWidth  := int(configureEvent.Width)
-	newHeight := int(configureEvent.Height)
-	sizeChanged :=
-		window.metrics.bounds.Dx() != newWidth ||
-		window.metrics.bounds.Dy() != newHeight
+	oldBounds := window.metrics.bounds
 	window.updateBounds()
+	newBounds := window.metrics.bounds
+
+	sizeChanged :=
+		oldBounds.Dx() != newBounds.Dx() ||
+		oldBounds.Dy() != newBounds.Dy()
 
 	if sizeChanged {
-		configureEvent = window.compressConfigureNotify(configureEvent)
 		window.reallocateCanvas()
 
 		// TODO figure out what to do with this

textbox.go

@@ -222,7 +222,7 @@ func (this *textBox) drawDot (can canvas.Canvas) {
 
 func (this *textBox) textOffset () image.Point {
 	return this.InnerBounds().Min.
-		Sub(this.scroll).
+		Add(this.scroll).
 		Sub(this.drawer.LayoutBoundsSpace().Min)
 }
 
@@ -294,6 +294,7 @@ func (this *textBox) doLayout () {
 	this.contentBounds = this.normalizedLayoutBoundsSpace()
 	this.constrainScroll()
 	this.contentBounds = this.contentBounds.Add(this.scroll)
+	// println(this.InnerBounds().String(), this.contentBounds.String())
 
 	if previousContentBounds != this.contentBounds {
 		this.on.contentBoundsChange.Broadcast()
@@ -308,19 +309,19 @@ func (this *textBox) constrainScroll () {
 	// X
 	if width <= innerBounds.Dx() {
 		this.scroll.X = 0
-	} else if this.scroll.X < 0 {
+	} else if this.scroll.X > 0 {
 		this.scroll.X = 0
-	} else if this.scroll.X > width - innerBounds.Dx() {
-		this.scroll.X = width - innerBounds.Dx()
+	} else if this.scroll.X < innerBounds.Dx() - width  {
+		this.scroll.X =  innerBounds.Dx() - width
 	}
 
 	// Y
 	if height <= innerBounds.Dy() {
 		this.scroll.Y = 0
-	} else if this.scroll.Y < 0 {
+	} else if this.scroll.Y > 0 {
 		this.scroll.Y = 0
-	} else if this.scroll.Y > height - innerBounds.Dy() {
-		this.scroll.Y = height - innerBounds.Dy()
+	} else if this.scroll.Y < innerBounds.Dy() - height {
+		this.scroll.Y = innerBounds.Dy() - height
 	}
 }
 
@@ -333,16 +334,16 @@ func (this *textBox) scrollToDot () {
 
 	// X
 	if dot.X < innerBounds.Min.X + em {
-		scroll.X -= innerBounds.Min.X - dot.X + em
+		scroll.X += innerBounds.Min.X - dot.X + em
 	} else if dot.X > innerBounds.Max.X - em {
-		scroll.X += dot.X - innerBounds.Max.X + em
+		scroll.X -= dot.X - innerBounds.Max.X + em
 	}
 
 	// Y
 	if dot.Y < innerBounds.Min.Y + lineHeight {
-		scroll.Y -= innerBounds.Min.Y - dot.Y + lineHeight
+		scroll.Y += innerBounds.Min.Y - dot.Y + lineHeight
 	} else if dot.Y > innerBounds.Max.Y - lineHeight {
-		scroll.Y += dot.Y - innerBounds.Max.Y + lineHeight
+		scroll.Y -= dot.Y - innerBounds.Max.Y + lineHeight
 	}
 	
 	this.ScrollTo(scroll)