Update internal system

internal/system/attribute.go

@@ -1,26 +1,48 @@
 package system
 
 import "git.tebibyte.media/tomo/tomo"
+import "git.tebibyte.media/tomo/backend/internal/util"
 
 type attrHierarchy [T tomo.Attr] struct {
-	style T
+	fallback T
-	user  T
+	style    util.Optional[T]
-	userExists bool
+	user     util.Optional[T]
+}
+
+func (this *attrHierarchy[T]) SetFallback (fallback T) {
+	this.fallback = fallback
 }
 
 func (this *attrHierarchy[T]) SetStyle (style T) (different bool) {
-	styleEquals := this.style.Equals(style)
+	styleEquals := false
-	this.style = style
+	if previous, ok := this.style.Value(); ok {
-	return !styleEquals && !this.userExists
+		styleEquals = previous.Equals(style)
+	}
+	this.style.Set(style)
+	return !styleEquals && !this.user.Exists()
+}
+
+func (this *attrHierarchy[T]) UnsetStyle () (different bool) {
+	different = this.style.Exists()
+	this.style.Unset()
+	return different
 }
 
 func (this *attrHierarchy[T]) SetUser (user T) (different bool) {
-	userEquals := this.user.Equals(user)
+	userEquals := false
-	this.user = user
+	if previous, ok := this.user.Value(); ok {
-	this.userExists = true
+		userEquals = previous.Equals(user)
+	}
+	this.user.Set(user)
 	return !userEquals
 }
 
+func (this *attrHierarchy[T]) UnsetUser () (different bool) {
+	different = this.user.Exists()
+	this.user.Unset()
+	return different
+}
+
 func (this *attrHierarchy[T]) Set (attr T, user bool) (different bool) {
 	if user {
 		return this.SetUser(attr)
@@ -29,10 +51,20 @@ func (this *attrHierarchy[T]) Set (attr T, user bool) (different bool) {
 	}
 }
 
-func (this *attrHierarchy[T]) Value () T {
+func (this *attrHierarchy[T]) Unset (user bool) (different bool) {
-	if this.userExists {
+	if user {
-		return this.user
+		return this.UnsetUser()
 	} else {
-		return this.style
+		return this.UnsetStyle()
+	}
+}
+
+func (this *attrHierarchy[T]) Value () T {
+	if user, ok := this.user.Value(); ok {
+		return user
+	} else if style, ok := this.style.Value(); ok{
+		return style
+	} else {
+		return this.fallback
 	}
 }

internal/system/box.go

@@ -14,11 +14,11 @@ type box struct {
 	parent parent
 	outer  anyBox
 
-	tags            util.Set[string]
+	tags             util.Set[string]
-	role            tomo.Role
+	role             tomo.Role
-	lastStyleNonce  int
+	lastStyleNonce   int
-	lastIconsNonce  int
+	lastIconSetNonce int
-	styleApplicator *styleApplicator
+	styleApplicator  *styleApplicator
 
 	minSize             util.Memo[image.Point]
 	bounds              image.Rectangle
@@ -41,7 +41,6 @@ type box struct {
 	focused bool
 	pressed bool
 	
-
 	canvas util.Memo[canvas.Canvas]
 	drawer canvas.Drawer
 
@@ -71,6 +70,7 @@ func (this *System) newBox (outer anyBox) *box {
 		drawer:  outer,
 		tags:    make(util.Set[string]),
 	}
+	box.attrColor.SetFallback(tomo.AColor(color.Transparent))
 	box.canvas = util.NewMemo (func () canvas.Canvas {
 		if box.parent == nil { return nil }
 		parentCanvas := box.parent.getCanvas()
@@ -141,6 +141,10 @@ func (this *box) SetAttr (attr tomo.Attr) {
 	this.outer.setAttr(attr, true)
 }
 
+func (this *box) UnsetAttr (kind tomo.AttrKind) {
+	this.outer.unsetAttr(kind, true)
+}
+
 func (this *box) SetDNDData (dat data.Data) {
 	this.dndData = dat
 }
@@ -201,18 +205,7 @@ func (this *box) setAttr (attr tomo.Attr, user bool) {
 	case tomo.AttrBorder:
 		previousBorderSum := this.borderSum()
 		different         := this.attrBorder.Set(attr, user)
-
+		this.handleBorderChange(previousBorderSum, different)
-		// only invalidate the layout if the border is sized differently
-		if this.borderSum() != previousBorderSum {
-			this.invalidateLayout()
-			this.invalidateMinimum()
-		}
-
-		// if the border takes up the same amount of space, only invalidate the
-		// drawing if it looks different
-		if different {
-			this.invalidateDraw()
-		}
 		
 	case tomo.AttrMinimumSize:
 		if this.attrMinimumSize.Set(attr, user) {
@@ -220,7 +213,42 @@ func (this *box) setAttr (attr tomo.Attr, user bool) {
 		}
 		
 	case tomo.AttrPadding:
-		if this.attrPadding.Set(attr, true) {
+		if this.attrPadding.Set(attr, user) {
+			this.invalidateLayout()
+			this.invalidateMinimum()
+		}
+	}
+}
+
+func (this *box) unsetAttr (kind tomo.AttrKind, user bool) {
+	switch kind {
+	case tomo.AttrKindColor:
+		if this.attrColor.Unset(user) {
+			this.invalidateDraw()
+		}
+		
+	case tomo.AttrKindTexture:
+		if this.attrTexture.Unset(user) {
+			this.invalidateDraw()
+		}
+		
+	case tomo.AttrKindTextureMode:
+		if this.attrTextureMode.Unset(user) {
+			this.invalidateDraw()
+		}
+		
+	case tomo.AttrKindBorder:
+		previousBorderSum := this.borderSum()
+		different         := this.attrBorder.Unset(user)
+		this.handleBorderChange(previousBorderSum, different)
+	
+	case tomo.AttrKindMinimumSize:
+		if this.attrMinimumSize.Unset(user) {
+			this.invalidateMinimum()
+		}
+		
+	case tomo.AttrKindPadding:
+		if this.attrPadding.Unset(user) {
 			this.invalidateLayout()
 			this.invalidateMinimum()
 		}
@@ -531,7 +559,21 @@ func (this *box) recursiveRedo () {
 }
 
 func (this *box) recursiveLoseCanvas () {
-	this.canvas.InvalidateTo(nil)
+	this.canvas.Invalidate()
+}
+
+func (this *box) handleBorderChange (previousBorderSum tomo.Inset, different bool) {
+	// only invalidate the layout if the border is sized differently
+	if this.borderSum() != previousBorderSum {
+		this.invalidateLayout()
+		this.invalidateMinimum()
+	}
+
+	// if the border takes up the same amount of space, only invalidate the
+	// drawing if it looks different
+	if different {
+		this.invalidateDraw()
+	}
 }
 
 func (this *box) invalidateStyle () {
@@ -578,9 +620,9 @@ func (this *box) recursiveReApply () {
 	}
 
 	// icons
-	hierarchyIconsNonce := this.getIconsNonce()
+	hierarchyIconSetNonce := this.getIconSetNonce()
-	if this.lastIconsNonce != hierarchyIconsNonce {
+	if this.lastIconSetNonce != hierarchyIconSetNonce {
-		this.lastIconsNonce = hierarchyIconsNonce
+		this.lastIconSetNonce = hierarchyIconSetNonce
 		this.on.iconSetChange.Broadcast()
 	}
 }
@@ -629,7 +671,7 @@ func (this *box) getStyleNonce () int {
 	return this.getHierarchy().getStyleNonce()
 }
 
-func (this *box) getIconsNonce () int {
+func (this *box) getIconSetNonce () int {
 	// should panic if not in the tree
-	return this.getHierarchy().getIconsNonce()
+	return this.getHierarchy().getIconSetNonce()
 }

internal/system/containerbox.go

@@ -186,6 +186,53 @@ func (this *containerBox) setAttr (attr tomo.Attr, user bool) {
 	}
 }
 
+func (this *containerBox) unsetAttr (kind tomo.AttrKind, user bool) {
+	switch kind {
+	case tomo.AttrKindColor:
+		if this.attrColor.Unset(user) {
+			this.invalidateTransparentChildren()
+			this.invalidateDraw()
+		}
+		
+	case tomo.AttrKindTexture:
+		if this.attrTexture.Unset(user) {
+			this.invalidateTransparentChildren()
+			this.invalidateDraw()
+		}
+		
+	case tomo.AttrKindTextureMode:
+		if this.attrTextureMode.Unset(user) {
+			this.invalidateTransparentChildren()
+			this.invalidateDraw()
+		}
+
+	case tomo.AttrKindGap:
+		if this.attrGap.Unset(user) {
+			this.invalidateLayout()
+			this.invalidateMinimum()
+		}
+		
+	case tomo.AttrKindAlign:
+		if this.attrAlign.Unset(user) {
+			this.invalidateLayout()
+		}
+		
+	case tomo.AttrKindOverflow:
+		if this.attrOverflow.Unset(user) {
+			this.invalidateLayout()
+			this.invalidateMinimum()
+		}
+		
+	case tomo.AttrKindLayout:
+		if this.attrLayout.Unset(user) {
+			this.invalidateLayout()
+			this.invalidateMinimum()
+		}
+
+	default: this.box.unsetAttr(kind, user)
+	}
+}
+
 func (this *containerBox) recommendedHeight (width int) int {
 	layout := this.attrLayout.Value().Layout
 	if layout == nil || !this.attrOverflow.Value().Y {

internal/system/hierarchy.go

@@ -4,6 +4,7 @@ import "image"
 import "git.tebibyte.media/tomo/tomo"
 import "git.tebibyte.media/tomo/tomo/input"
 import "git.tebibyte.media/tomo/tomo/canvas"
+import "git.tebibyte.media/tomo/backend/style"
 import "git.tebibyte.media/tomo/backend/internal/util"
 
 // Hierarchy is coupled to a tomo.Window implementation, and manages a tree of
@@ -168,16 +169,24 @@ func (this *Hierarchy) getWindow () tomo.Window {
 	return this.link.GetWindow()
 }
 
-func (this *Hierarchy) getStyle () *tomo.Style {
+func (this *Hierarchy) getStyle () *style.Style {
 	return this.system.style
 }
 
+func (this *Hierarchy) getIconSet () style.IconSet {
+	return this.system.iconSet
+}
+
+func (this *Hierarchy) getFaceSet () style.FaceSet {
+	return this.system.faceSet
+}
+
 func (this *Hierarchy) getStyleNonce () int {
 	return this.system.styleNonce
 }
 
-func (this *Hierarchy) getIconsNonce () int {
+func (this *Hierarchy) getIconSetNonce () int {
-	return this.system.iconsNonce
+	return this.system.iconSetNonce
 }
 
 func (this *Hierarchy) getCanvas () canvas.Canvas {

internal/system/internal-iface.go

@@ -75,6 +75,9 @@ type anyBox interface {
 	// setAttr sets an attribute at the user or style level depending
 	// on the value of user.
 	setAttr   (attr tomo.Attr, user bool)
+	// unsetAttr unsets an attribute at the user or style level depending
+	// on the value of user.
+	unsetAttr (kind tomo.AttrKind, user bool)
 
 	// propagate recursively calls a function on this anyBox, and all of its
 	// children (if applicable) The normal propagate behavior calls the

internal/system/style.go

@@ -1,11 +1,12 @@
 package system
 
 import "git.tebibyte.media/tomo/tomo"
+import "git.tebibyte.media/tomo/backend/style"
 
 type styleApplicator struct {
-	style *tomo.Style
+	style *style.Style
 	role  tomo.Role
-	rules []tomo.Rule
+	rules []style.Rule
 }
 
 func (this *styleApplicator) apply (box anyBox) {
@@ -25,7 +26,7 @@ func (this *styleApplicator) apply (box anyBox) {
 	}
 
 	// compile list of attributes by searching through the cached ruleset
-	attrs := make(tomo.AttrSet)
+	attrs := make(style.AttrSet)
 	for _, rule := range this.rules {
 		satisifed := true
 		for _, tag := range rule.Tags {

internal/system/system.go

@@ -2,8 +2,8 @@ package system
 
 import "io"
 import "image"
-import "git.tebibyte.media/tomo/tomo"
 import "git.tebibyte.media/tomo/tomo/canvas"
+import "git.tebibyte.media/tomo/backend/style"
 import "git.tebibyte.media/tomo/backend/internal/util"
 
 // System is coupled to a tomo.Backend implementation, and manages Hierarchies
@@ -11,9 +11,11 @@ import "git.tebibyte.media/tomo/backend/internal/util"
 type System struct {
 	link BackendLink
 
-	style      *tomo.Style
+	style        *style.Style
-	styleNonce int
+	iconSet      style.IconSet
-	iconsNonce int
+	faceSet      style.FaceSet
+	styleNonce   int
+	iconSetNonce int
 	
 	hierarchies util.Set[*Hierarchy]
 }
@@ -43,9 +45,9 @@ func New (link BackendLink) *System {
 	}
 }
 
-// SetStyle sets the tomo.Style that is applied to objects, and notifies them
+// SetStyle sets the style that is applied to objects, and notifies them
 // that the style has changed.
-func (this *System) SetStyle (style *tomo.Style) {
+func (this *System) SetStyle (style *style.Style) {
 	this.style = style
 	this.styleNonce ++
 	for hierarchy := range this.hierarchies {
@@ -53,14 +55,21 @@ func (this *System) SetStyle (style *tomo.Style) {
 	}
 }
 
-// SetIconSet notifies objects that the icons have changed.
+// SetIconSet sets the icon set that provides icon textures, and notifies
-func (this *System) SetIconSet (iconSet tomo.IconSet) {
+// objects that the icons have changed.
-	this.iconsNonce ++
+func (this *System) SetIconSet (iconSet style.IconSet) {
+	this.iconSet = iconSet
+	this.iconSetNonce ++
 	for hierarchy := range this.hierarchies {
 		hierarchy.setIconSet()
 	}
 }
 
+// SetFaceSet sets the face set that provides font faces.
+func (this *System) SetFaceSet (faceSet style.FaceSet) {
+	this.faceSet = faceSet
+}
+
 func (this *System) removeHierarchy (hierarchy *Hierarchy) {
 	delete(this.hierarchies, hierarchy)
 }

internal/system/textbox.go

@@ -2,6 +2,7 @@ package system
 
 import "image"
 import "image/color"
+import "golang.org/x/image/font"
 import "git.tebibyte.media/tomo/tomo"
 import "golang.org/x/image/math/fixed"
 import "git.tebibyte.media/tomo/typeset"
@@ -9,6 +10,7 @@ import "git.tebibyte.media/tomo/tomo/text"
 import "git.tebibyte.media/tomo/tomo/input"
 import "git.tebibyte.media/tomo/tomo/event"
 import "git.tebibyte.media/tomo/tomo/canvas"
+import "git.tebibyte.media/tomo/backend/internal/util"
 
 type textBox struct {
 	*box
@@ -31,6 +33,7 @@ type textBox struct {
 	dot         text.Dot
 
 	drawer typeset.Drawer
+	face   util.Cycler[font.Face]
 
 	on struct {
 		contentBoundsChange event.FuncBroadcaster
@@ -41,6 +44,8 @@ type textBox struct {
 func (this *System) NewTextBox () tomo.TextBox {
 	box := &textBox { }
 	box.box = this.newBox(box)
+	box.attrTextColor.SetFallback(tomo.ATextColor(color.Black))
+	box.attrDotColor.SetFallback(tomo.ADotColor(color.RGBA { G: 255, B: 255, A: 255}))
 	return box
 }
 
@@ -106,9 +111,8 @@ func (this *textBox) OnDotChange (callback func ()) event.Cookie {
 func (this *textBox) Draw (can canvas.Canvas) {
 	if can == nil { return }
 
-	texture     := this.attrTexture.Value().Texture
+	texture := this.attrTexture.Value().Texture
-	col         := this.attrColor.Value().Color
+	col     := this.attrColor.Value().Color
-	if col == nil { col = color.Transparent }
 	
 	this.drawBorders(can)
 	
@@ -124,9 +128,8 @@ func (this *textBox) Draw (can canvas.Canvas) {
 		this.drawDot(can)
 	}
 
-	if this.attrFace.Value().Face != nil {
+	if this.face.Value() != nil {
 		textColor := this.attrTextColor.Value().Color
-		if textColor == nil { textColor = color.Black }
 		this.drawer.Draw(can, textColor, this.textOffset())
 	}
 }
@@ -145,23 +148,22 @@ func (this *textBox) setAttr (attr tomo.Attr, user bool) {
 		
 	case tomo.AttrFace:
 		if this.attrFace.Set(attr, user) {
-			this.drawer.SetFace(attr.Face)
+			this.handleFaceChange()
-			this.invalidateMinimum()
-			this.invalidateLayout()
 		}
 		
 	case tomo.AttrWrap:
 		if this.attrWrap.Set(attr, user) {
-			this.drawer.SetWrap(bool(attr))
+			this.drawer.SetWrap(bool(this.attrWrap.Value()))
 			this.invalidateMinimum()
 			this.invalidateLayout()
 		}
 		
 	case tomo.AttrAlign:
 		if this.attrAlign.Set(attr, user) {
+			align := this.attrAlign.Value()
 			this.drawer.SetAlign (
-				typeset.Align(attr.X),
+				typeset.Align(align.X),
-				typeset.Align(attr.Y))
+				typeset.Align(align.Y))
 			this.invalidateDraw()
 		}
 		
@@ -175,6 +177,49 @@ func (this *textBox) setAttr (attr tomo.Attr, user bool) {
 	}
 }
 
+func (this *textBox) unsetAttr (kind tomo.AttrKind, user bool) {
+	switch kind {
+	case tomo.AttrKindTextColor:
+		if this.attrTextColor.Unset(user) && !this.dot.Empty() {
+			this.invalidateDraw()
+		}
+		
+	case tomo.AttrKindDotColor:
+		if this.attrDotColor.Unset(user) && !this.dot.Empty() {
+			this.invalidateDraw()
+		}
+		
+	case tomo.AttrKindFace:
+		if this.attrFace.Unset(user) {
+			this.handleFaceChange()
+		}
+		
+	case tomo.AttrKindWrap:
+		if this.attrWrap.Unset(user) {
+			this.drawer.SetWrap(bool(this.attrWrap.Value()))
+			this.invalidateMinimum()
+			this.invalidateLayout()
+		}
+		
+	case tomo.AttrKindAlign:
+		if this.attrAlign.Unset(user) {
+			align := this.attrAlign.Value()
+			this.drawer.SetAlign (
+				typeset.Align(align.X),
+				typeset.Align(align.Y))
+			this.invalidateDraw()
+		}
+		
+	case tomo.AttrKindOverflow:
+		if this.attrOverflow.Unset(user) {
+			this.invalidateMinimum()
+			this.invalidateLayout()
+		}
+		
+	default: this.box.unsetAttr(kind, user)
+	}
+}
+
 func roundPt (point fixed.Point26_6) image.Point {
 	return image.Pt(point.X.Round(), point.Y.Round())
 }
@@ -184,13 +229,11 @@ func fixPt (point image.Point) fixed.Point26_6 {
 }
 
 func (this *textBox) drawDot (can canvas.Canvas) {
-	if this.attrFace.Value().Face == nil { return }
+	face := this.face.Value()
+	if face == nil { return }
 
-	face      := this.attrFace.Value().Face
 	textColor := this.attrTextColor.Value().Color
 	dotColor  := this.attrDotColor.Value().Color
-	if textColor == nil { textColor = color.Black }
-	if dotColor  == nil { dotColor  = color.RGBA { G: 255, B: 255, A: 255 } }
 	
 	pen := can.Pen()
 
@@ -447,3 +490,16 @@ func (this *textBox) scrollToDot () {
 	
 	this.ScrollTo(scroll)
 }
+
+func (this *textBox) handleFaceChange () {
+	hierarchy := this.getHierarchy()
+	if hierarchy != nil { return }
+	faceSet := hierarchy.getFaceSet()
+	if faceSet != nil { return }
+	
+	face := faceSet.Face(tomo.Face(this.attrFace.Value()))
+	this.face.Set(face, face)
+	this.drawer.SetFace(face)
+	this.invalidateMinimum()
+	this.invalidateLayout()
+}