Redesign icon: wood texture shield with darken-blended Syncthing motif

Replace procedural icon renderer with pre-rendered textured icons:
- Use Stammtisch wood texture as shield face (crop tabletop planks)
- Apply Syncthing motif via darken blend ("warpaint on wood" effect)
- Fix Syncthing logo geometry: asymmetric node placement (76°/116°/168°
  gaps) with offset hub, matching the official SVG
- Metal rim with rivets and directional lighting
- Embed pre-rendered PNGs via go:embed (no runtime rendering)
- Icon generator in cmd/icongen/ takes wood texture as input

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

internal/icons/render.go

@@ -2,245 +2,74 @@ package icons
 
 import (
 	"bytes"
+	_ "embed"
 	"encoding/binary"
-	"image/color"
 	"image/png"
-	"math"
 	"runtime"
-
-	"github.com/fogleman/gg"
 )
 
-const iconSize = 64
+// Pre-rendered tray icons (64px) generated from Stammtisch wood texture
+// with the Syncthing motif applied via darken blend.
+// Regenerate with: go run ./cmd/icongen/ -wood /path/to/stammtisch.png
 
-// Render generates a tray icon for the given state.
+//go:embed tray_idle.png
+var trayIdlePNG []byte
+
+//go:embed tray_syncing.png
+var traySyncingPNG []byte
+
+//go:embed tray_paused.png
+var trayPausedPNG []byte
+
+//go:embed tray_error.png
+var trayErrorPNG []byte
+
+//go:embed tray_disconnected.png
+var trayDisconnectedPNG []byte
+
+// Render returns the tray icon for the given state.
 // Returns ICO bytes on Windows, PNG bytes on other platforms.
 func Render(state State) ([]byte, error) {
-	return RenderSize(state, iconSize)
-}
-
-// RenderSize generates an icon at the given pixel size.
-func RenderSize(state State, size int) ([]byte, error) {
-	dc := gg.NewContext(size, size)
-	drawShieldIcon(dc, state, float64(size))
-
-	var buf bytes.Buffer
-	if err := png.Encode(&buf, dc.Image()); err != nil {
-		return nil, err
-	}
-
-	pngData := buf.Bytes()
+	pngData := trayPNG(state)
 	if runtime.GOOS == "windows" {
-		return wrapPNGInICO(pngData, size, size), nil
+		return wrapPNGInICO(pngData, 64, 64), nil
 	}
 	return pngData, nil
 }
 
-// RenderPNG generates a PNG icon at the given size, regardless of platform.
+func trayPNG(state State) []byte {
+	switch state {
+	case StateIdle:
+		return trayIdlePNG
+	case StateSyncing:
+		return traySyncingPNG
+	case StatePaused:
+		return trayPausedPNG
+	case StateError:
+		return trayErrorPNG
+	case StateDisconnected:
+		return trayDisconnectedPNG
+	default:
+		return trayDisconnectedPNG
+	}
+}
+
+// RenderPNG returns a PNG icon at 64px for the given state.
 func RenderPNG(state State, size int) ([]byte, error) {
-	dc := gg.NewContext(size, size)
-	drawShieldIcon(dc, state, float64(size))
-
-	var buf bytes.Buffer
-	if err := png.Encode(&buf, dc.Image()); err != nil {
-		return nil, err
-	}
-	return buf.Bytes(), nil
+	// Pre-rendered icons are only 64px; return them directly.
+	// For other sizes, the static assets in assets/ should be used.
+	return trayPNG(state), nil
 }
 
-// Shield color palette — warm wood tones inspired by Stammtisch
-var (
-	shieldRim   = color.RGBA{55, 42, 30, 255}     // dark iron rim
-	shieldOuter = color.RGBA{130, 82, 38, 255}    // darker wood ring
-	shieldMid   = color.RGBA{175, 118, 58, 255}   // warm wood body
-	shieldInner = color.RGBA{195, 140, 72, 255}   // lighter wood center
-	shieldLight = color.RGBA{210, 162, 95, 255}   // highlight zone
-	grainDark   = color.RGBA{145, 90, 40, 200}    // wood grain shadow
-	rivetBody   = color.RGBA{105, 95, 80, 255}    // iron rivet
-	rivetShine  = color.RGBA{160, 150, 130, 255}  // rivet highlight
-	bossEdge    = color.RGBA{80, 65, 45, 255}     // boss rim
-	bossBody    = color.RGBA{145, 130, 105, 255}  // boss metal
-	bossShine   = color.RGBA{190, 180, 160, 255}  // boss highlight
-	motifShadow = color.RGBA{40, 30, 20, 100}     // dark outline behind motif
-)
-
-func drawShieldIcon(dc *gg.Context, state State, s float64) {
-	cx := s / 2
-	cy := s / 2
-	sc := s / 64 // scale factor relative to 64px base
-
-	// 1. Shield rim (dark outer ring)
-	rimR := s * 0.47
-	dc.DrawCircle(cx, cy, rimR)
-	dc.SetColor(shieldRim)
-	dc.Fill()
-
-	// 2. Shield face — layered wood rings
-	faceR := s * 0.42
-	drawWoodFace(dc, cx, cy, faceR)
-
-	// 3. Wood grain arcs (skip at very small sizes)
-	if s >= 48 {
-		drawWoodGrain(dc, cx, cy, faceR, sc)
+// IconSize returns the size of the pre-rendered tray icons.
+func IconSize() (int, int) {
+	data := trayIdlePNG
+	img, err := png.Decode(bytes.NewReader(data))
+	if err != nil {
+		return 64, 64
 	}
-
-	// 4. Rivets around rim (skip below 32px)
-	if s >= 32 {
-		rivetCount := 12
-		if s < 48 {
-			rivetCount = 8
-		}
-		drawRivets(dc, cx, cy, rimR-2*sc, sc, rivetCount)
-	}
-
-	// 5. Syncthing motif — "warpaint" in state color
-	drawSyncthingMotif(dc, cx, cy, faceR, state, sc)
-
-	// 6. Center boss
-	drawBoss(dc, cx, cy, sc)
-}
-
-func drawWoodFace(dc *gg.Context, cx, cy, r float64) {
-	layers := []struct {
-		frac float64
-		c    color.RGBA
-	}{
-		{1.00, shieldOuter},
-		{0.90, shieldMid},
-		{0.72, shieldInner},
-		{0.48, shieldLight},
-		{0.30, shieldInner},
-	}
-	for _, l := range layers {
-		dc.DrawCircle(cx, cy, r*l.frac)
-		dc.SetColor(l.c)
-		dc.Fill()
-	}
-}
-
-func drawWoodGrain(dc *gg.Context, cx, cy, r, sc float64) {
-	dc.SetColor(grainDark)
-	dc.SetLineWidth(math.Max(0.8, 0.7*sc))
-	dc.SetLineCap(gg.LineCapRound)
-
-	arcs := []struct{ radius, startDeg, sweepDeg float64 }{
-		{0.83, 25, 55},
-		{0.83, 195, 50},
-		{0.62, 95, 65},
-		{0.62, 275, 50},
-		{0.42, 5, 75},
-		{0.42, 165, 60},
-	}
-	for _, a := range arcs {
-		dc.DrawArc(cx, cy, r*a.radius, degToRad(a.startDeg), degToRad(a.startDeg+a.sweepDeg))
-		dc.Stroke()
-	}
-}
-
-func drawRivets(dc *gg.Context, cx, cy, r, sc float64, count int) {
-	rr := math.Max(1.2, 1.8*sc) // rivet radius
-
-	for i := 0; i < count; i++ {
-		a := float64(i) * 2 * math.Pi / float64(count)
-		rx := cx + r*math.Cos(a)
-		ry := cy + r*math.Sin(a)
-
-		dc.DrawCircle(rx, ry, rr)
-		dc.SetColor(rivetBody)
-		dc.Fill()
-
-		// Highlight
-		if sc >= 1.0 {
-			dc.DrawCircle(rx-rr*0.2, ry-rr*0.3, rr*0.45)
-			dc.SetColor(rivetShine)
-			dc.Fill()
-		}
-	}
-}
-
-func drawSyncthingMotif(dc *gg.Context, cx, cy, faceR float64, state State, sc float64) {
-	stateCol := colorForState(state)
-	ringR := faceR * 0.58
-	lineW := math.Max(1.8, 2.8*sc)
-	nodeR := math.Max(2.2, 3.2*sc)
-
-	// Node positions: top, bottom-left, bottom-right
-	nodeAngles := []float64{-90, 150, 30}
-	nodes := make([][2]float64, 3)
-	for i, deg := range nodeAngles {
-		rad := degToRad(deg)
-		nodes[i] = [2]float64{
-			cx + ringR*math.Cos(rad),
-			cy + ringR*math.Sin(rad),
-		}
-	}
-
-	// --- Shadow layer (dark outline behind everything for contrast) ---
-	shadowOff := math.Max(0.5, 0.8*sc)
-	dc.SetColor(motifShadow)
-	dc.SetLineWidth(lineW + 2*shadowOff)
-	dc.SetLineCap(gg.LineCapRound)
-
-	// Shadow ring
-	dc.DrawCircle(cx, cy, ringR)
-	dc.Stroke()
-
-	// Shadow spokes
-	for _, n := range nodes {
-		dc.DrawLine(cx, cy, n[0], n[1])
-	}
-	dc.Stroke()
-
-	// Shadow nodes
-	for _, n := range nodes {
-		dc.DrawCircle(n[0], n[1], nodeR+shadowOff)
-		dc.Fill()
-	}
-
-	// --- Motif layer (state-colored) ---
-	dc.SetColor(stateCol)
-	dc.SetLineWidth(lineW)
-	dc.SetLineCap(gg.LineCapRound)
-
-	// Ring
-	dc.DrawCircle(cx, cy, ringR)
-	dc.Stroke()
-
-	// Spokes from center to nodes
-	for _, n := range nodes {
-		dc.DrawLine(cx, cy, n[0], n[1])
-	}
-	dc.Stroke()
-
-	// Node circles
-	for _, n := range nodes {
-		dc.DrawCircle(n[0], n[1], nodeR)
-		dc.SetColor(stateCol)
-		dc.Fill()
-	}
-}
-
-func drawBoss(dc *gg.Context, cx, cy, sc float64) {
-	br := math.Max(2.5, 4.5*sc)
-
-	// Edge ring
-	dc.DrawCircle(cx, cy, br+0.8*sc)
-	dc.SetColor(bossEdge)
-	dc.Fill()
-
-	// Body
-	dc.DrawCircle(cx, cy, br)
-	dc.SetColor(bossBody)
-	dc.Fill()
-
-	// Highlight (upper-left)
-	dc.DrawCircle(cx-br*0.22, cy-br*0.28, br*0.5)
-	dc.SetColor(bossShine)
-	dc.Fill()
-}
-
-func degToRad(deg float64) float64 {
-	return deg * math.Pi / 180
+	b := img.Bounds()
+	return b.Dx(), b.Dy()
 }
 
 // wrapPNGInICO wraps raw PNG bytes in a minimal ICO container.