Fix bug where nil cells would sometimes render without styling

backends/x/draw.go

@@ -49,11 +49,25 @@ func (backend *Backend) drawCells (forceRedraw bool) (areas []image.Rectangle) {
 
 		cell := backend.application.GetForRendering(x, y)
 		content := cell.Rune()
+		style   := cell.Style()
 
-		if forceRedraw && content < 32 { continue }
+		if
+			forceRedraw &&
+			content < 32 &&
+			style & (
+				stone.StyleHighlight |
+				stone.StyleUnderline) == 0 {
+			
+			continue
+		}
 
 		areas = append(areas, backend.boundsOfCell(x, y))
-		backend.drawRune(x, y, content, cell.Color(), !forceRedraw)
+		backend.drawRune (
+			x, y,
+			content,
+			cell.Color(),
+			cell.Style(),
+			!forceRedraw)
 	}}
 
 	if backend.drawBufferBounds && forceRedraw {
@@ -74,115 +88,205 @@ func (backend *Backend) drawRune (
 	x, y int,
 	character rune,
 	runeColor stone.Color,
+	runeStyle stone.Style,
 	drawBackground bool,
 ) {
 	// TODO: cache these draws as non-transparent buffers with the
 	// application background color as the background. that way, we won't
 	// need to redraw the characters *or* composite them.
 
-	if drawBackground {
+	face := backend.font.normal
+
+	highlight := runeStyle & stone.StyleHighlight > 0
+	bold      := runeStyle & stone.StyleBold      > 0
+	italic    := runeStyle & stone.StyleItalic    > 0
+
+	boldTransform   := false
+	italicTransform := false
+
+	switch {
+	case bold && italic:
+		if backend.font.boldItalic == nil {
+			switch {
+			case
+				backend.font.bold == nil && backend.font.italic != nil,
+				backend.font.bold != nil && backend.font.italic != nil:
+				
+				boldTransform = true
+				face = backend.font.italic
+			case backend.font.italic == nil && backend.font.bold != nil:
+				italicTransform = true
+				face = backend.font.bold
+			default:
+				boldTransform   = true
+				italicTransform = true
+			}
+		} else {
+			face = backend.font.boldItalic
+		}
+	case bold:
+		if backend.font.bold == nil {
+			boldTransform = true
+		} else {
+			face = backend.font.bold
+		}
+	case italic:
+		if backend.font.italic == nil {
+			italicTransform = true
+		} else {
+			face = backend.font.italic
+		}
+	}
+	
+	var background xgraphics.BGRA
+	var foreground xgraphics.BGRA
+
+	if highlight {
+		background = backend.colors[runeColor]
+		foreground = backend.colors[stone.ColorBackground]
+	} else {
+		background = backend.colors[stone.ColorBackground]
+		foreground = backend.colors[runeColor]
+	}
+
+	if drawBackground || highlight {
 		fillRectangle (
-			&image.Uniform {
-				C: backend.config.Color(stone.ColorBackground),
-			},
+			&image.Uniform { C: background },
 			backend.canvas,
 			backend.boundsOfCell(x, y))
 	}
 
-	if character < 32 { return }
-
 	origin := backend.originOfCell(x, y + 1)
-	destinationRectangle, mask, maskPoint, _, ok := backend.font.face.Glyph (
-		fixed.Point26_6 {
-			X: fixed.I(origin.X),
-			Y: fixed.I(origin.Y),
-		},
-		character)
 
-	if !ok {
-		strokeRectangle (
-			&image.Uniform {
-				C: backend.config.Color(stone.ColorForeground),
+	if character >= 32 {
+		destinationRectangle, mask, maskPoint, _, ok := face.Glyph (
+			fixed.Point26_6 {
+				X: fixed.I(origin.X),
+				Y: fixed.I(origin.Y),
 			},
-			backend.canvas,
-			backend.boundsOfCell(x, y))
-		return
+			character)
+
+		if !ok {
+			strokeRectangle (
+				&image.Uniform { C: foreground },
+				backend.canvas,
+				backend.boundsOfCell(x, y))
+			return
+		}
+
+		if backend.drawCellBounds {
+			strokeRectangle (
+				&image.Uniform { C: foreground },
+				backend.canvas,
+				backend.boundsOfCell(x, y))
+		}
+
+		// alphaMask, isAlpha := mask.(*image.Alpha)
+		// if isAlpha {
+			// backend.sprayRuneMaskAlpha (
+				// alphaMask, destinationRectangle,
+				// maskPoint, foreground, background)
+		// } else {
+			backend.sprayRuneMask (
+				mask, destinationRectangle,
+				maskPoint, foreground, background,
+				italicTransform, boldTransform)
+		// }
 	}
 
-	if backend.drawCellBounds {
-		strokeRectangle (
-			&image.Uniform {
-				C: backend.config.Color(stone.ColorForeground),
-			},
-			backend.canvas,
-			backend.boundsOfCell(x, y))
-	}
-
-	// cue a series of pointless optimizations
-	alphaMask, isAlpha := mask.(*image.Alpha)
-	if isAlpha {
-		backend.sprayRuneMaskAlpha (
-			alphaMask, destinationRectangle,
-			maskPoint, backend.colors[runeColor])
-	} else {
-		backend.sprayRuneMask (
-			mask, destinationRectangle,
-			maskPoint, backend.colors[runeColor])
+	// underline
+	if runeStyle & stone.StyleUnderline > 0 {
+		maxX := origin.X + backend.metrics.cellWidth
+		y :=
+			origin.Y -
+			backend.metrics.descent
+		for x := origin.X; x < maxX; x ++ {
+			backend.canvas.SetBGRA(x, y, foreground)
+		}
 	}
 }
 
 func (backend *Backend) sprayRuneMask (
-	mask      image.Image,
-	bounds    image.Rectangle,
-	maskPoint image.Point,
-	fill      xgraphics.BGRA,
+	mask       image.Image,
+	bounds     image.Rectangle,
+	maskPoint  image.Point,
+	fill       xgraphics.BGRA,
+	background xgraphics.BGRA,
+	italic     bool,
+	bold       bool,
 ) {
 	maxX := bounds.Max.X - bounds.Min.X
 	maxY := bounds.Max.Y - bounds.Min.Y
 	
 	for y := 0; y < maxY; y ++ {
-	for x := 0; x < maxX; x ++ {
-		_, _, _,
-		alpha := mask.At(x + maskPoint.X, y + maskPoint.Y).RGBA()
-		backend.canvas.SetBGRA (
-			x + bounds.Min.X,
-			y + bounds.Min.Y - backend.metrics.descent,
-			xgraphics.BlendBGRA (
-				backend.colors[stone.ColorBackground],
-				xgraphics.BGRA {
-					R: fill.R,
-					G: fill.G,
-					B: fill.B,
-					A: uint8(alpha >> 8),
-				}))
-	}}
+		var previousAlpha uint32
+		offset := 0
+		if italic {
+			offset = (maxY - y) / 4
+		}
+		for x := 0; x < maxX; x ++ {
+			_, _, _,
+			alpha := mask.At(x + maskPoint.X, y + maskPoint.Y).RGBA()
+			currentAlpha := alpha
+			if bold && previousAlpha > alpha {
+				alpha = previousAlpha
+			}
+			backend.canvas.SetBGRA (
+				x + bounds.Min.X + offset,
+				y + bounds.Min.Y - backend.metrics.descent,
+				xgraphics.BlendBGRA (
+					background,
+					xgraphics.BGRA {
+						R: fill.R,
+						G: fill.G,
+						B: fill.B,
+						A: uint8(alpha >> 8),
+					}))
+			previousAlpha = currentAlpha
+		}
+
+		if bold {
+			backend.canvas.SetBGRA (
+				bounds.Max.X + offset,
+				y + bounds.Min.Y - backend.metrics.descent,
+				xgraphics.BlendBGRA (
+					background,
+					xgraphics.BGRA {
+						R: fill.R,
+						G: fill.G,
+						B: fill.B,
+						A: uint8(previousAlpha >> 8),
+					}))
+		}
+	}
 }
 
-func (backend *Backend) sprayRuneMaskAlpha (
-	mask      *image.Alpha,
-	bounds    image.Rectangle,
-	maskPoint image.Point,
-	fill      xgraphics.BGRA,
-) {
-	maxX := bounds.Max.X - bounds.Min.X
-	maxY := bounds.Max.Y - bounds.Min.Y
-	
-	for y := 0; y < maxY; y ++ {
-	for x := 0; x < maxX; x ++ {
-		alpha := mask.AlphaAt(x + maskPoint.X, y + maskPoint.Y).A
-		backend.canvas.SetBGRA (
-			x + bounds.Min.X,
-			y + bounds.Min.Y - backend.metrics.descent,
-			xgraphics.BlendBGRA (
-				backend.colors[stone.ColorBackground],
-				xgraphics.BGRA {
-					R: fill.R,
-					G: fill.G,
-					B: fill.B,
-					A: alpha,
-				}))
-	}}
-}
+// func (backend *Backend) sprayRuneMaskAlpha (
+	// mask       *image.Alpha,
+	// bounds     image.Rectangle,
+	// maskPoint  image.Point,
+	// fill       xgraphics.BGRA,
+	// background xgraphics.BGRA,
+// ) {
+	// maxX := bounds.Max.X - bounds.Min.X
+	// maxY := bounds.Max.Y - bounds.Min.Y
+	// 
+	// for y := 0; y < maxY; y ++ {
+	// for x := 0; x < maxX; x ++ {
+		// alpha := mask.AlphaAt(x + maskPoint.X, y + maskPoint.Y).A
+		// backend.canvas.SetBGRA (
+			// x + bounds.Min.X,
+			// y + bounds.Min.Y - backend.metrics.descent,
+			// xgraphics.BlendBGRA (
+				// background,
+				// xgraphics.BGRA {
+					// R: fill.R,
+					// G: fill.G,
+					// B: fill.B,
+					// A: alpha,
+				// }))
+	// }}
+// }
 
 func fillRectangle (
 	source      image.Image,

backends/x/factory.go

@@ -32,11 +32,20 @@ func factory (
 	}
 
 	// load font
-	backend.font.face = findAndLoadFont (
-		backend.config.FontName(),
+	backend.font.normal = findAndLoadFont (
+		backend.config.FontNameNormal(),
 		float64(backend.config.FontSize()))
-	if backend.font.face == nil {
-		backend.font.face = basicfont.Face7x13
+	backend.font.bold = findAndLoadFont (
+		backend.config.FontNameBold(),
+		float64(backend.config.FontSize()))
+	backend.font.italic = findAndLoadFont (
+		backend.config.FontNameItalic(),
+		float64(backend.config.FontSize()))
+	backend.font.boldItalic = findAndLoadFont (
+		backend.config.FontNameBoldItalic(),
+		float64(backend.config.FontSize()))
+	if backend.font.normal == nil {
+		backend.font.normal = basicfont.Face7x13
 	}
 
 	// pre-calculate colors
@@ -56,8 +65,8 @@ func factory (
 	}
 
 	// calculate metrics
-	metrics := backend.font.face.Metrics()
-	glyphAdvance, _ := backend.font.face.GlyphAdvance('M')
+	metrics := backend.font.normal.Metrics()
+	glyphAdvance, _ := backend.font.normal.GlyphAdvance('M')
 	backend.metrics.cellWidth  = glyphAdvance.Round()
 	backend.metrics.cellHeight = metrics.Height.Round()
 	backend.metrics.descent    = metrics.Descent.Round()

backends/x/x.go

@@ -27,7 +27,10 @@ type Backend struct {
 	lock sync.Mutex
 
 	font struct {
-		face font.Face
+		normal     font.Face
+		bold       font.Face
+		italic     font.Face
+		boldItalic font.Face
 	}
 
 	colors [8]xgraphics.BGRA

buffer.go

@@ -21,11 +21,11 @@ const (
 type Style uint8
 
 const (
-	StyleNormal     Style = iota
-	StyleBold       Style = iota >> 1
-	StyleItalic
-	StyleUnderline
-	StyleHighlight
+	StyleNormal     Style = 0
+	StyleBold       Style = 1
+	StyleItalic     Style = 2
+	StyleUnderline  Style = 4
+	StyleHighlight  Style = 8
 	StyleBoldItalic Style = StyleBold | StyleItalic
 )
 
@@ -44,7 +44,7 @@ func (cell Cell) Color () (color Color) {
 }
 
 // Style returns the styling information associated with the cell
-func (cell Cell) Style (style Style) {
+func (cell Cell) Style () (style Style) {
 	style = cell.style
 	return
 }

config.go

@@ -12,7 +12,10 @@ type Config struct {
 	padding  int
 	center   bool
 	fontSize int
-	fontName string
+	fontNameNormal     string
+	fontNameBold       string
+	fontNameItalic     string
+	fontNameBoldItalic string
 }
 
 // Color returns the color value at the specified index.
@@ -41,9 +44,27 @@ func (public *Config) FontSize () (fontSize int) {
 	return
 }
 
-// FontName specifies the name of the font to use.
-func (public *Config) FontName () (fontName string) {
-	fontName = public.fontName
+// FontNameNormal specifies the name of the font to use for normal text.
+func (public *Config) FontNameNormal () (fontName string) {
+	fontName = public.fontNameNormal
+	return
+}
+
+// FontNameBold specifies the name of the font to use for bold text.
+func (public *Config) FontNameBold () (fontName string) {
+	fontName = public.fontNameBold
+	return
+}
+
+// FontName specifies the name of the font to use for  text.
+func (public *Config) FontNameItalic () (fontName string) {
+	fontName = public.fontNameItalic
+	return
+}
+
+// FontName specifies the name of the font to use for  text.
+func (public *Config) FontNameBoldItalic () (fontName string) {
+	fontName = public.fontNameBoldItalic
 	return
 }
 
@@ -51,6 +72,9 @@ func (public *Config) load () {
 	public.private = config.Config {
 		LegalParameters: map[string] config.Type {
 			"fontNormal":      config.TypeString,
+			"fontBold":        config.TypeString,
+			"fontItalic":      config.TypeString,
+			"fontBoldItalic":  config.TypeString,
 			"fontSize":        config.TypeInteger,
 			"padding":         config.TypeInteger,
 			"center":          config.TypeBoolean,
@@ -65,10 +89,13 @@ func (public *Config) load () {
 		},
 		
 		Parameters: map[string] any {
-			"fontNormal": "",
-			"fontSize":   11,
-			"padding":    2,
-			"center":     false,
+			"fontNormal":     "",
+			"fontBold":       "",
+			"fontItalic":     "",
+			"fontBoldItalic": "",
+			"fontSize":       11,
+			"padding":        2,
+			"center":         false,
 			"colorBackground":
 				color.RGBA { R: 0, G: 0, B: 0, A: 0 },
 			"colorForeground":
@@ -91,10 +118,13 @@ func (public *Config) load () {
 	public.private.Load("stone")
 	params := public.private.Parameters
 
-	public.fontName = params["fontNormal"].(string)
-	public.fontSize = params["fontSize"].(int)
-	public.padding  = params["padding"].(int)
-	public.center   = params["center"].(bool)
+	public.fontNameNormal     = params["fontNormal"].(string)
+	public.fontNameBold       = params["fontBold"].(string)
+	public.fontNameItalic     = params["fontItalic"].(string)
+	public.fontNameBoldItalic = params["fontBoldItalic"].(string)
+	public.fontSize           = params["fontSize"].(int)
+	public.padding            = params["padding"].(int)
+	public.center             = params["center"].(bool)
 	
 	public.colors[ColorBackground] = params["colorBackground"].(color.RGBA)
 	public.colors[ColorForeground] = params["colorForeground"].(color.RGBA)

config/xdg.go

@@ -29,14 +29,14 @@ func init () {
 
 	configDirs = append(strings.Split(configDirsString, ":"), configHome)
 
-	configHome = os.Getenv("XDG_DATA_HOME")
-	if configHome == "" {
-		configHome = filepath.Join(homeDirectory, "/.local/share/")
+	dataHome = os.Getenv("XDG_DATA_HOME")
+	if dataHome == "" {
+		dataHome = filepath.Join(homeDirectory, "/.local/share/")
 	}
 
 	cacheHome = os.Getenv("XDG_CACHE_HOME")
 	if cacheHome == "" {
-		configHome = filepath.Join(homeDirectory, "/.cache/")
+		cacheHome = filepath.Join(homeDirectory, "/.cache/")
 	}
 }
 

examples/style/main.go

@@ -0,0 +1,77 @@
+package main
+
+import "os"
+import "fmt"
+import "image"
+import "math/rand"
+import _ "image/png"
+import "git.tebibyte.media/sashakoshka/stone"
+import _ "git.tebibyte.media/sashakoshka/stone/backends/x"
+
+var application = &stone.Application { }
+
+func main () {
+	application.SetTitle("style demo")
+	application.SetSize(11, 8)
+
+	iconFile16, err := os.Open("assets/scaffold16.png")
+	if err != nil { panic(err) }
+	icon16, _, err := image.Decode(iconFile16)
+	if err != nil { panic(err) }
+	iconFile16.Close()
+	iconFile32, err := os.Open("assets/scaffold32.png")
+	if err != nil { panic(err) }
+	icon32, _, err := image.Decode(iconFile32)
+	if err != nil { panic(err) }
+	iconFile16.Close()
+	
+	application.SetIcon([]image.Image { icon16, icon32 })
+	
+	application.OnStart(redraw)
+	application.OnResize(redraw)
+	application.OnPress(onPress)
+	
+	err = application.Run()
+	if err != nil { panic(err) }
+}
+
+func onPress (button stone.Button, modifiers stone.Modifiers) {
+	redraw()
+	application.Draw()
+}
+
+func redraw () {
+	width, _ := application.Size()
+	application.SetDot(0, 0)
+	fmt.Fprint (
+		application,
+		"normal\n",
+		"bold\n",
+		"italic\n",
+		"underline\n",
+		"all 3\n",
+		"highlighted\n",
+		"all 4\n",
+		"highlight?")
+	fillStyle(0, width, stone.StyleNormal)
+	fillStyle(1, width, stone.StyleBold)
+	fillStyle(2, width, stone.StyleItalic)
+	fillStyle(3, width, stone.StyleUnderline)
+	fillStyle(4, width, stone.StyleBoldItalic | stone.StyleUnderline)
+	fillStyle(5, width, stone.StyleHighlight)
+	fillStyle(6, width, stone.StyleBoldItalic | stone.StyleUnderline |
+		stone.StyleHighlight)
+
+	if rand.Int() % 2 == 0 {
+		fillStyle(7, width, stone.StyleNormal)
+	} else {
+		fillStyle(7, width, stone.StyleHighlight)
+	}
+}
+
+func fillStyle (yOffset, width int, style stone.Style) {
+	for x := 0; x < width; x ++ {
+		application.SetStyle(x, yOffset, style)
+		application.SetColor(x, yOffset, stone.Color(x % 7 + 1))
+	}
+}