xgb-render: slightly simplify

prototypes/xgb-xrender.go

@@ -11,6 +11,7 @@ import (
 	"golang.org/x/image/font/gofont/goregular"
 	"golang.org/x/image/math/fixed"
 	"image"
+	"image/draw"
 	"log"
 	"math/rand"
 )
@@ -223,33 +224,13 @@ func main() {
 		log.Fatalln(err)
 	}
 
-	c := freetype.NewContext()
-	c.SetDPI(96) // TODO: Take this from the screen or monitor.
-	c.SetFont(f)
-	c.SetFontSize(9)
-	c.SetSrc(image.White)
-	c.SetHinting(font.HintingFull)
-	// TODO: Seems like we want to use NRGBA. Or RGBA if the A is always 1.
-	// Or implement our own image.Image for direct gamma-corrected RGB!
-	nrgb := image.NewRGBA(image.Rect(0, 0, 36, 36))
-	c.SetClip(nrgb.Bounds())
-	c.SetDst(nrgb)
-
-	bounds := f.Bounds(c.PointToFixed(9 /* FIXME: Duplication. */))
-	log.Println("+%v", bounds)
-
-	// FIXME: Duplication.
-	opts := truetype.Options{
-		Size: 9,
-		DPI:  96,
+	opts := &truetype.Options{
+		Size:    9,
+		DPI:     96, // TODO: Take this from the screen or monitor.
+		Hinting: font.HintingFull,
 	}
+	face := truetype.NewFace(f, opts)
 
-	// TODO: Seems this satisfies the sfnt interface, DrawString just adds
-	// kerning and DrawMask on top.
-	face := truetype.NewFace(f, &opts)
-	_ = face
-
-	// TODO: Figure out a way to load glyphs into XRender.
 	var rgbFormat render.Pictformat
 	for _, pf := range pformats.Formats {
 		// Hopefully. Might want to check ARGB/BGRA.
@@ -268,17 +249,28 @@ func main() {
 	// NOTE: A depth of 24 will not work, the server always rejects it.
 	_ = render.CreateGlyphSet(X, gsid, rgbFormat)
 
+	//bounds := f.Bounds(c.PointToFixed(opts.Size))
+	//log.Println("+%v", bounds)
+
+	// TODO: Seems like we want to use NRGBA. Or RGBA if the A is always 1.
+	// Or implement our own image.Image for direct gamma-corrected RGB!
+	nrgb := image.NewRGBA(image.Rect(0, 0, 36, 36))
+	//nrgb.Bounds()
+
 	for r := rune(32); r < 128; r++ {
+		dr, mask, maskp, advance, ok := face.Glyph(
+			fixed.P(0, 18) /* subpixel destination location */, r)
+		if !ok {
+			log.Println("skip")
+			continue
+		}
+
 		for i := 0; i < len(nrgb.Pix); i++ {
 			nrgb.Pix[i] = 0
 		}
 
-		advance, err := c.DrawString(string(r), fixed.P(18, 18))
-		_, _ = advance, err
-		if err != nil {
-			log.Println("skip")
-			continue
-		}
+		draw.Draw(nrgb, dr, mask, maskp, draw.Src)
+		_ = advance
 
 		_ = render.AddGlyphs(X, gsid, 1, []uint32{uint32(r)},
 			[]render.Glyphinfo{{