Added a case specifier to the theme API

This will allow themes to pull off some cool dirty tricks without
screwing anything up

elements/basic/button.go

@@ -6,6 +6,8 @@ import "git.tebibyte.media/sashakoshka/tomo/theme"
 import "git.tebibyte.media/sashakoshka/tomo/artist"
 import "git.tebibyte.media/sashakoshka/tomo/elements/core"
 
+var buttonCase = theme.C("basic", "button")
+
 // Button is a clickable button.
 type Button struct {
 	*core.Core
@@ -114,7 +116,7 @@ func (element *Button) SetText (text string) {
 	element.text = text
 	element.drawer.SetText([]rune(text))
 	textBounds := element.drawer.LayoutBounds()
-	_, inset := theme.ButtonPattern(theme.PatternState { })
+	_, inset := theme.ButtonPattern(theme.PatternState { Case: buttonCase })
 	minimumSize := inset.Inverse().Apply(textBounds).Inset(-theme.Padding())
 	element.core.SetMinimumSize(minimumSize.Dx(), minimumSize.Dy())
 	if element.core.HasImage () {
@@ -127,6 +129,7 @@ func (element *Button) draw () {
 	bounds := element.core.Bounds()
 
 	pattern, inset := theme.ButtonPattern(theme.PatternState {
+		Case: buttonCase,
 		Disabled: !element.Enabled(),
 		Selected: element.Selected(),
 		Pressed:  element.pressed,
@@ -148,6 +151,7 @@ func (element *Button) draw () {
 	offset.X -= textBounds.Min.X
 
 	foreground, _ := theme.ForegroundPattern (theme.PatternState {
+		Case: buttonCase,
 		Disabled: !element.Enabled(),
 	})
 	element.drawer.Draw(element.core, foreground, offset)

elements/basic/checkbox.go

@@ -6,6 +6,8 @@ import "git.tebibyte.media/sashakoshka/tomo/theme"
 import "git.tebibyte.media/sashakoshka/tomo/artist"
 import "git.tebibyte.media/sashakoshka/tomo/elements/core"
 
+var checkboxCase = theme.C("basic", "checkbox")
+
 // Checkbox is a toggle-able checkbox with a label.
 type Checkbox struct {
 	*core.Core
@@ -140,10 +142,13 @@ func (element *Checkbox) draw () {
 	bounds := element.core.Bounds()
 	boxBounds := image.Rect(0, 0, bounds.Dy(), bounds.Dy())
 
-	backgroundPattern, _ := theme.BackgroundPattern(theme.PatternState { })
+	backgroundPattern, _ := theme.BackgroundPattern(theme.PatternState {
+		Case: checkboxCase,
+	})
 	artist.FillRectangle ( element.core, backgroundPattern, bounds)
 
 	pattern, inset := theme.ButtonPattern(theme.PatternState {
+		Case: checkboxCase,
 		Disabled: !element.Enabled(),
 		Selected: element.Selected(),
 		Pressed:  element.pressed,
@@ -159,6 +164,7 @@ func (element *Checkbox) draw () {
 	offset.X -= textBounds.Min.X
 
 	foreground, _ := theme.ForegroundPattern (theme.PatternState {
+		Case: checkboxCase,
 		Disabled: !element.Enabled(),
 	})
 	element.drawer.Draw(element.core, foreground, offset)

elements/basic/container.go

@@ -6,6 +6,8 @@ import "git.tebibyte.media/sashakoshka/tomo/theme"
 import "git.tebibyte.media/sashakoshka/tomo/artist"
 import "git.tebibyte.media/sashakoshka/tomo/elements/core"
 
+var containerCase = theme.C("basic", "container")
+
 // Container is an element capable of containg other elements, and arranging
 // them in a layout.
 type Container struct {
@@ -473,7 +475,9 @@ func (element *Container) recalculate () {
 func (element *Container) draw () {
 	bounds := element.core.Bounds()
 
-	pattern, _ := theme.BackgroundPattern(theme.PatternState { })
+	pattern, _ := theme.BackgroundPattern (theme.PatternState {
+		Case: containerCase,
+	})
 	artist.FillRectangle(element.core, pattern, bounds)
 
 	for _, entry := range element.children {

elements/basic/label.go

@@ -5,6 +5,8 @@ import "git.tebibyte.media/sashakoshka/tomo/theme"
 import "git.tebibyte.media/sashakoshka/tomo/artist"
 import "git.tebibyte.media/sashakoshka/tomo/elements/core"
 
+var labelCase = theme.C("basic", "label")
+
 // Label is a simple text box.
 type Label struct {
 	*core.Core
@@ -108,12 +110,16 @@ func (element *Label) updateMinimumSize () {
 func (element *Label) draw () {
 	bounds := element.core.Bounds()
 
-	pattern, _ := theme.BackgroundPattern(theme.PatternState { })
+	pattern, _ := theme.BackgroundPattern(theme.PatternState {
+		Case: labelCase,
+	})
 	artist.FillRectangle(element.core, pattern, bounds)
 
 	textBounds := element.drawer.LayoutBounds()
 
-	foreground, _ := theme.ForegroundPattern (theme.PatternState { })
+	foreground, _ := theme.ForegroundPattern (theme.PatternState {
+		Case: labelCase,
+	})
 	element.drawer.Draw (element.core, foreground, image.Point {
 		X: 0 - textBounds.Min.X,
 		Y: 0 - textBounds.Min.Y,

elements/basic/list.go

@@ -7,6 +7,8 @@ import "git.tebibyte.media/sashakoshka/tomo/theme"
 import "git.tebibyte.media/sashakoshka/tomo/artist"
 import "git.tebibyte.media/sashakoshka/tomo/elements/core"
 
+var listCase = theme.C("basic", "list")
+
 // List is an element that contains several objects that a user can select.
 type List struct {
 	*core.Core
@@ -164,7 +166,9 @@ func (element *List) ScrollAxes () (horizontal, vertical bool) {
 }
 
 func (element *List) scrollViewportHeight () (height int) {
-	_, inset := theme.ListPattern(theme.PatternState { })
+	_, inset := theme.ListPattern(theme.PatternState {
+		Case: listCase,
+	})
 	return element.Bounds().Dy() - inset[0] - inset[2]
 }
 
@@ -330,7 +334,9 @@ func (element *List) changeSelectionBy (delta int) (updated bool) {
 }
 
 func (element *List) resizeEntryToFit (entry ListEntry) (resized ListEntry) {
-	_, inset := theme.ListPattern(theme.PatternState { })
+	_, inset := theme.ListPattern(theme.PatternState {
+		Case: listCase,
+	})
 	entry.Collapse(element.forcedMinimumWidth - inset[3] - inset[1])
 	return entry
 }
@@ -357,7 +363,9 @@ func (element *List) updateMinimumSize () {
 		minimumHeight = element.contentHeight
 	}
 
-	_, inset := theme.ListPattern(theme.PatternState { })
+	_, inset := theme.ListPattern(theme.PatternState {
+		Case: listCase,
+	})
 	minimumWidth  += inset[1] + inset[3]
 	minimumHeight += inset[0] + inset[2]
 
@@ -368,6 +376,7 @@ func (element *List) draw () {
 	bounds := element.Bounds()
 
 	pattern, inset := theme.ListPattern(theme.PatternState {
+		Case: listCase,
 		Disabled: !element.Enabled(),
 		Selected: element.Selected(),
 	})
@@ -386,6 +395,7 @@ func (element *List) draw () {
 
 		if element.selectedEntry == index {
 			pattern, _ := theme.ItemPattern(theme.PatternState {
+				Case: listEntryCase,
 				On: true,
 			})
 			artist.FillRectangle (

elements/basic/listentry.go

@@ -5,6 +5,8 @@ import "git.tebibyte.media/sashakoshka/tomo"
 import "git.tebibyte.media/sashakoshka/tomo/theme"
 import "git.tebibyte.media/sashakoshka/tomo/artist"
 
+var listEntryCase = theme.C("basic", "listEntry")
+
 // ListEntry is an item that can be added to a list.
 type ListEntry struct {
 	drawer artist.TextDrawer
@@ -41,7 +43,8 @@ func (entry *ListEntry) updateBounds () {
 		entry.bounds.Max.X = entry.drawer.LayoutBounds().Dx()
 	}
 	
-	_, inset := theme.ItemPattern(theme.PatternState { })
+	_, inset := theme.ItemPattern(theme.PatternState {
+	})
 	entry.bounds.Max.Y += inset[0] + inset[2]
 	
 	entry.textPoint =
@@ -56,7 +59,9 @@ func (entry *ListEntry) Draw (
 ) (
 	updatedRegion image.Rectangle,
 ) {
-	foreground, _ := theme.ForegroundPattern (theme.PatternState { })
+	foreground, _ := theme.ForegroundPattern (theme.PatternState {
+		Case: listEntryCase,
+	})
 	return entry.drawer.Draw (
 		destination,
 		foreground,

elements/basic/scrollcontainer.go

@@ -6,6 +6,10 @@ import "git.tebibyte.media/sashakoshka/tomo/theme"
 import "git.tebibyte.media/sashakoshka/tomo/artist"
 import "git.tebibyte.media/sashakoshka/tomo/elements/core"
 
+var scrollContainerCase     = theme.C("basic", "scrollContainer")
+var scrollBarHorizontalCase = theme.C("basic", "scrollBarHorizontal")
+var scrollBarVerticalCase   = theme.C("basic", "scrollBarVertical")
+
 // ScrollContainer is a container that is capable of holding a scrollable
 // element.
 type ScrollContainer struct {
@@ -273,12 +277,24 @@ func (element *ScrollContainer) clearChildEventHandlers (child tomo.Scrollable)
 }
 
 func (element *ScrollContainer) recalculate () {
-	_, gutterInset := theme.GutterPattern(theme.PatternState { })
+	_, gutterInsetHorizontal := theme.GutterPattern(theme.PatternState {
+		Case: scrollBarHorizontalCase,
+	})
+	_, gutterInsetVertical := theme.GutterPattern(theme.PatternState {
+		Case: scrollBarHorizontalCase,
+	})
 
 	horizontal := &element.horizontal
 	vertical   := &element.vertical
 	bounds     := element.Bounds()
-	thickness  := theme.HandleWidth() + gutterInset[3] + gutterInset[1]
+	thicknessHorizontal :=
+		theme.HandleWidth() +
+		gutterInsetHorizontal[3] +
+		gutterInsetHorizontal[1]
+	thicknessVertical :=
+		theme.HandleWidth() +
+		gutterInsetVertical[3] +
+		gutterInsetVertical[1]
 
 	// calculate child size
 	element.childWidth  = bounds.Dx()
@@ -292,24 +308,24 @@ func (element *ScrollContainer) recalculate () {
 
 	// if enabled, give substance to the gutters
 	if horizontal.exists {
-		horizontal.gutter.Min.Y = bounds.Max.Y - thickness
+		horizontal.gutter.Min.Y = bounds.Max.Y - thicknessHorizontal
 		horizontal.gutter.Max.X = bounds.Max.X
 		horizontal.gutter.Max.Y = bounds.Max.Y
 		if vertical.exists {
-			horizontal.gutter.Max.X -= thickness
+			horizontal.gutter.Max.X -= thicknessVertical
 		}
-		element.childHeight -= thickness
-		horizontal.track = gutterInset.Apply(horizontal.gutter)
+		element.childHeight -= thicknessHorizontal
+		horizontal.track = gutterInsetHorizontal.Apply(horizontal.gutter)
 	}
 	if vertical.exists {
-		vertical.gutter.Min.X = bounds.Max.X - thickness
+		vertical.gutter.Min.X = bounds.Max.X - thicknessVertical
 		vertical.gutter.Max.X = bounds.Max.X
 		vertical.gutter.Max.Y = bounds.Max.Y
 		if horizontal.exists {
-			vertical.gutter.Max.Y -= thickness
+			vertical.gutter.Max.Y -= thicknessHorizontal
 		}
-		element.childWidth -= thickness
-		vertical.track = gutterInset.Apply(vertical.gutter)
+		element.childWidth -= thicknessVertical
+		vertical.track = gutterInsetVertical.Apply(vertical.gutter)
 	}
 
 	// if enabled, calculate the positions of the bars
@@ -351,7 +367,9 @@ func (element *ScrollContainer) recalculate () {
 
 func (element *ScrollContainer) draw () {
 	artist.Paste(element.core, element.child, image.Point { })
-	deadPattern, _ := theme.DeadPattern(theme.PatternState { })
+	deadPattern, _ := theme.DeadPattern(theme.PatternState {
+		Case: scrollContainerCase,
+	})
 	artist.FillRectangle (
 		element, deadPattern,
 		image.Rect (
@@ -365,11 +383,13 @@ func (element *ScrollContainer) draw () {
 
 func (element *ScrollContainer) drawHorizontalBar () {
 	gutterPattern, _ := theme.GutterPattern (theme.PatternState {
+		Case: scrollBarHorizontalCase,
 		Disabled: !element.horizontal.enabled,
 	})
 	artist.FillRectangle(element, gutterPattern, element.horizontal.gutter)
 	
 	handlePattern, _ := theme.HandlePattern (theme.PatternState {
+		Case: scrollBarHorizontalCase,
 		Disabled: !element.horizontal.enabled,
 		Pressed:  element.horizontal.dragging,
 	})
@@ -378,11 +398,13 @@ func (element *ScrollContainer) drawHorizontalBar () {
 
 func (element *ScrollContainer) drawVerticalBar () {
 	gutterPattern, _ := theme.GutterPattern (theme.PatternState {
+		Case: scrollBarVerticalCase,
 		Disabled: !element.vertical.enabled,
 	})
 	artist.FillRectangle(element, gutterPattern, element.vertical.gutter)
 	
 	handlePattern, _ := theme.HandlePattern (theme.PatternState {
+		Case: scrollBarVerticalCase,
 		Disabled: !element.vertical.enabled,
 		Pressed:  element.vertical.dragging,
 	})
@@ -408,11 +430,24 @@ func (element *ScrollContainer) dragVerticalBar (mousePosition image.Point) {
 }
 
 func (element *ScrollContainer) updateMinimumSize () {
-	_, gutterInset := theme.GutterPattern(theme.PatternState { })
-	thickness  := theme.HandleWidth() + gutterInset[3] + gutterInset[1]
+	_, gutterInsetHorizontal := theme.GutterPattern(theme.PatternState {
+		Case: scrollBarHorizontalCase,
+	})
+	_, gutterInsetVertical := theme.GutterPattern(theme.PatternState {
+		Case: scrollBarHorizontalCase,
+	})
+
+	thicknessHorizontal :=
+		theme.HandleWidth() +
+		gutterInsetHorizontal[3] +
+		gutterInsetHorizontal[1]
+	thicknessVertical :=
+		theme.HandleWidth() +
+		gutterInsetVertical[3] +
+		gutterInsetVertical[1]
 	
-	width  := thickness
-	height := thickness
+	width  := thicknessHorizontal
+	height := thicknessVertical
 	if element.child != nil {
 		childWidth, childHeight := element.child.MinimumSize()
 		width  += childWidth

elements/basic/spacer.go

@@ -4,6 +4,8 @@ import "git.tebibyte.media/sashakoshka/tomo/theme"
 import "git.tebibyte.media/sashakoshka/tomo/artist"
 import "git.tebibyte.media/sashakoshka/tomo/elements/core"
 
+var spacerCase = theme.C("basic", "spacer")
+
 // Spacer can be used to put space between two elements..
 type Spacer struct {
 	*core.Core
@@ -43,11 +45,13 @@ func (element *Spacer) draw () {
 
 	if element.line {
 		pattern, _ := theme.ForegroundPattern(theme.PatternState {
+			Case: spacerCase,
 			Disabled: true,
 		})
 		artist.FillRectangle(element.core, pattern, bounds)
 	} else {
 		pattern, _ := theme.BackgroundPattern(theme.PatternState {
+			Case: spacerCase,
 			Disabled: true,
 		})
 		artist.FillRectangle(element.core, pattern, bounds)

elements/basic/switch.go

@@ -6,6 +6,8 @@ import "git.tebibyte.media/sashakoshka/tomo/theme"
 import "git.tebibyte.media/sashakoshka/tomo/artist"
 import "git.tebibyte.media/sashakoshka/tomo/elements/core"
 
+var switchCase = theme.C("basic", "switch")
+
 // Switch is a toggle-able on/off switch with an optional label. It is
 // functionally identical to Checkbox, but plays a different semantic role.
 type Switch struct {
@@ -147,7 +149,9 @@ func (element *Switch) draw () {
 	bounds := element.core.Bounds()
 	handleBounds := image.Rect(0, 0, bounds.Dy(), bounds.Dy())
 	gutterBounds := image.Rect(0, 0, bounds.Dy() * 2, bounds.Dy())
-	backgroundPattern, _ := theme.BackgroundPattern(theme.PatternState { })
+	backgroundPattern, _ := theme.BackgroundPattern(theme.PatternState {
+		Case: switchCase,
+	})
 	artist.FillRectangle ( element.core, backgroundPattern, bounds)
 
 	if element.checked {
@@ -165,6 +169,7 @@ func (element *Switch) draw () {
 	}
 
 	gutterPattern, _ := theme.GutterPattern(theme.PatternState {
+		Case: switchCase,
 		Disabled: !element.Enabled(),
 		Selected: element.Selected(),
 		Pressed:  element.pressed,
@@ -172,6 +177,7 @@ func (element *Switch) draw () {
 	artist.FillRectangle(element.core, gutterPattern, gutterBounds)
 	
 	handlePattern, _ := theme.HandlePattern(theme.PatternState {
+		Case: switchCase,
 		Disabled: !element.Enabled(),
 		Selected: element.Selected(),
 		Pressed:  element.pressed,
@@ -187,6 +193,7 @@ func (element *Switch) draw () {
 	offset.X -= textBounds.Min.X
 
 	foreground, _ := theme.ForegroundPattern (theme.PatternState {
+		Case: switchCase,
 		Disabled: !element.Enabled(),
 	})
 	element.drawer.Draw(element.core, foreground, offset)

elements/basic/textbox.go

@@ -7,6 +7,8 @@ import "git.tebibyte.media/sashakoshka/tomo/artist"
 import "git.tebibyte.media/sashakoshka/tomo/textmanip"
 import "git.tebibyte.media/sashakoshka/tomo/elements/core"
 
+var textBoxCase = theme.C("basic", "textBox")
+
 // TextBox is a single-line text input.
 type TextBox struct {
 	*core.Core
@@ -237,7 +239,9 @@ func (element *TextBox) OnScrollBoundsChange (callback func ()) {
 
 func (element *TextBox) updateMinimumSize () {
 	textBounds := element.placeholderDrawer.LayoutBounds()
-	_, inset := theme.InputPattern(theme.PatternState { })
+	_, inset := theme.InputPattern(theme.PatternState {
+		Case: textBoxCase,
+	})
 	element.core.SetMinimumSize (
 		textBounds.Dx() +
 		theme.Padding() * 2 + inset[3] + inset[1],
@@ -273,6 +277,7 @@ func (element *TextBox) draw () {
 
 	// FIXME: take index into account
 	pattern, inset := theme.InputPattern(theme.PatternState {
+		Case: textBoxCase,
 		Disabled: !element.Enabled(),
 		Selected: element.Selected(),
 	})
@@ -286,6 +291,7 @@ func (element *TextBox) draw () {
 			Y: theme.Padding() + inset[0],
 		}
 		foreground, _ := theme.ForegroundPattern(theme.PatternState {
+			Case: textBoxCase,
 			Disabled: true,
 		})
 		element.placeholderDrawer.Draw (
@@ -300,6 +306,7 @@ func (element *TextBox) draw () {
 			Y: theme.Padding() + inset[0],
 		}
 		foreground, _ := theme.ForegroundPattern(theme.PatternState {
+			Case: textBoxCase,
 			Disabled: !element.Enabled(),
 		})
 		element.valueDrawer.Draw (
@@ -311,7 +318,9 @@ func (element *TextBox) draw () {
 			// cursor
 			cursorPosition := element.valueDrawer.PositionOf (
 				element.cursor)
-			foreground, _ := theme.ForegroundPattern(theme.PatternState { })
+			foreground, _ := theme.ForegroundPattern(theme.PatternState {
+				Case: textBoxCase,
+			})
 			artist.Line (
 				element.core,
 				foreground, 1,

elements/fun/clock.go

@@ -7,6 +7,8 @@ import "git.tebibyte.media/sashakoshka/tomo/theme"
 import "git.tebibyte.media/sashakoshka/tomo/artist"
 import "git.tebibyte.media/sashakoshka/tomo/elements/core"
 
+var clockCase = theme.C("fun", "clock")
+
 // AnalogClock can display the time of day in an analog format.
 type AnalogClock struct {
 	*core.Core
@@ -41,13 +43,19 @@ func (element *AnalogClock) SetTime (newTime time.Time) {
 func (element *AnalogClock) draw () {
 	bounds := element.core.Bounds()
 
-	pattern, inset := theme.SunkenPattern(theme.PatternState { })
+	pattern, inset := theme.SunkenPattern(theme.PatternState {
+		Case: clockCase,
+	})
 	artist.FillRectangle(element, pattern, bounds)
 
 	bounds = inset.Apply(bounds)
 
-	foreground, _ := theme.ForegroundPattern(theme.PatternState { })
-	accent,     _ := theme.AccentPattern(theme.PatternState { })
+	foreground, _ := theme.ForegroundPattern(theme.PatternState {
+		Case: clockCase,
+	})
+	accent, _ := theme.AccentPattern(theme.PatternState {
+		Case: clockCase,
+	})
 
 	for hour := 0; hour < 12; hour ++ {
 		element.radialLine (

theme/patterns.go

@@ -3,10 +3,28 @@ package theme
 import "image"
 import "git.tebibyte.media/sashakoshka/tomo/artist"
 
+// Case sepecifies what kind of element is using a pattern. It contains a
+// namespace parameter and an element parameter. The element parameter does not
+// necissarily need to match an element name, but if it can, it should. Both
+// parameters should be written in camel case. Themes can change their styling
+// based on this parameter for fine-grained control over the look and feel of
+// specific elements.
+type Case struct { Namespace, Element string } 
+ 
+// C can be used as shorthand to generate a case struct as used in PatternState.
+func C (namespace, element string) (c Case) {
+	return Case {
+		Namespace: namespace,
+		Element: element,
+	}
+}
+
 // PatternState lists parameters which can change the appearance of some
 // patterns. For example, passing a PatternState with Selected set to true may
 // result in a pattern that has a colored border within it.
 type PatternState struct {
+	Case
+
 	// On should be set to true if the element that is using this pattern is
 	// in some sort of "on" state, such as if a checkbox is checked or a
 	// switch is toggled on. This is only necessary if the element in