perf(colorpicker): incremental magnifier redraws, frame-paced commits

2026-10-30 23:17:51 -04:00 · 2026-08-20 19:17:25 -04:00
1 parent 52244c01f7
commit e6a5fae190
@@ -3,6 +3,7 @@ package main
 import (
 	"fmt"
 	"os"
+	"runtime/debug"

 	"github.com/AvengeMedia/DankMaterialShell/core/internal/clipboard"
 	"github.com/AvengeMedia/DankMaterialShell/core/internal/colorpicker"
@@ -96,6 +97,10 @@ func runColorPick(cmd *cobra.Command, args []string) {
 		Notify:       colorNotify,
 	}

+	// One-shot process holding a few screen-sized buffers: skip GC cycles while it runs.
+	debug.SetGCPercent(-1)
+	debug.SetMemoryLimit(1 << 30)
+
 	picker := colorpicker.New(config)
 	color, err := picker.Run()
 	if err != nil {
@@ -35,18 +35,19 @@ type Output struct {
 }

 type LayerSurface struct {
-	output      *Output
-	state       *SurfaceState
-	wlSurface   *client.Surface
-	layerSurf   *wlr_layer_shell.ZwlrLayerSurfaceV1
-	viewport    *wp_viewporter.WpViewport
-	wlPools     [2]*client.ShmPool
-	wlBuffers   [2]*client.Buffer
-	slotBusy    [2]bool
-	needsRedraw bool
-	scopyBuffer *client.Buffer
-	configured  bool
-	hidden      bool
+	output       *Output
+	state        *SurfaceState
+	wlSurface    *client.Surface
+	layerSurf    *wlr_layer_shell.ZwlrLayerSurfaceV1
+	viewport     *wp_viewporter.WpViewport
+	wlPools      [2]*client.ShmPool
+	wlBuffers    [2]*client.Buffer
+	slotBusy     [2]bool
+	needsRedraw  bool
+	framePending bool
+	scopyBuffer  *client.Buffer
+	configured   bool
+	hidden       bool
 }

 type Picker struct {
@@ -66,6 +67,8 @@ type Picker struct {
 	viewporter *wp_viewporter.WpViewporter
 	colorMgr   *wp_color_management.WpColorManagerV1

+	compositorVersion uint32
+
 	shortcutsInhibitMgr *keyboard_shortcuts_inhibit.ZwpKeyboardShortcutsInhibitManagerV1
 	shortcutsInhibitor  *keyboard_shortcuts_inhibit.ZwpKeyboardShortcutsInhibitorV1

@@ -166,9 +169,10 @@ func (p *Picker) checkDone() {
 	}
 }

+// flushRedraws paints queued surfaces, at most once per compositor frame each.
 func (p *Picker) flushRedraws() {
 	for _, ls := range p.surfaces {
-		if !ls.needsRedraw {
+		if !ls.needsRedraw || ls.framePending {
 			continue
 		}
 		p.redrawSurface(ls)
@@ -215,6 +219,7 @@ func (p *Picker) handleGlobal(e client.RegistryGlobalEvent) {
 		compositor := client.NewCompositor(p.ctx)
 		if err := p.registry.Bind(e.Name, e.Interface, e.Version, compositor); err == nil {
 			p.compositor = compositor
+			p.compositorVersion = e.Version
 		}

 	case client.ShmInterfaceName:
@@ -547,17 +552,18 @@ func (p *Picker) captureForSurface(ls *LayerSurface) {

 func (p *Picker) redrawSurface(ls *LayerSurface) {
 	slot := ls.state.FrontIndex()
-	if ls.slotBusy[slot] {
+	if ls.slotBusy[slot] || ls.framePending {
 		ls.needsRedraw = true
 		return
 	}

 	var renderBuf *ShmBuffer
+	var damage []rect
 	switch {
 	case ls.hidden:
-		renderBuf = ls.state.RedrawScreenOnly()
+		renderBuf, damage = ls.state.RedrawScreenOnly()
 	default:
-		renderBuf = ls.state.Redraw()
+		renderBuf, damage = ls.state.Redraw()
 	}
 	if renderBuf == nil {
 		return
@@ -604,7 +610,25 @@ func (p *Picker) redrawSurface(ls *LayerSurface) {
 		_ = ls.wlSurface.SetBufferScale(bufferScale)
 	}
 	_ = ls.wlSurface.Attach(ls.wlBuffers[slot], 0, 0)
-	_ = ls.wlSurface.Damage(0, 0, int32(logicalW), int32(logicalH))
+	switch {
+	case p.compositorVersion < 4:
+		_ = ls.wlSurface.Damage(0, 0, int32(logicalW), int32(logicalH))
+	default:
+		for _, r := range damage {
+			r = r.clip(renderBuf.Width, renderBuf.Height)
+			if r.w <= 0 || r.h <= 0 {
+				continue
+			}
+			_ = ls.wlSurface.DamageBuffer(int32(r.x), int32(r.y), int32(r.w), int32(r.h))
+		}
+	}
+	if cb, err := ls.wlSurface.Frame(); err == nil {
+		ls.framePending = true
+		cb.SetDoneHandler(func(client.CallbackDoneEvent) {
+			_ = cb.Destroy()
+			ls.framePending = false
+		})
+	}
 	_ = ls.wlSurface.Commit()

 	ls.state.SwapBuffers()
@@ -34,6 +34,10 @@ type SurfaceState struct {

 	renderBufs [2]*ShmBuffer
 	front      int
+	primed     [2]bool
+	drawn      [2][]rect
+	shown      []rect
+	fullDamage bool

 	scale  int32
 	scaleX float64
@@ -212,6 +216,10 @@ func (s *SurfaceState) ensureRenderBuffers() {
 	if s.screenBuf == nil {
 		return
 	}
+	s.primed = [2]bool{}
+	s.drawn = [2][]rect{}
+	s.shown = nil
+	s.fullDamage = true

 	width := s.screenBuf.Width
 	height := s.screenBuf.Height
@@ -306,21 +314,70 @@ func (s *SurfaceState) SwapBuffers() {
 	s.mu.Unlock()
 }

-func (s *SurfaceState) Redraw() *ShmBuffer {
+// rect is a buffer-pixel area, clipped on use.
+type rect struct{ x, y, w, h int }
+
+func (r rect) clip(w, h int) rect {
+	x1, y1 := max(r.x, 0), max(r.y, 0)
+	x2, y2 := min(r.x+r.w, w), min(r.y+r.h, h)
+	return rect{x1, y1, max(x2-x1, 0), max(y2-y1, 0)}
+}
+
+func magnifierRect(cx, cy int) rect {
+	const reach = magnifierRadius + 2
+	return rect{cx - reach, cy - reach, 2*reach + 1, 2*reach + 1}
+}
+
+// restore puts screen pixels back under the front buffer's previous overlay and
+// records cur as its new footprint. It returns what differs from the frame on screen.
+func (s *SurfaceState) restore(dst *ShmBuffer, cur []rect) []rect {
+	i := s.front
+	switch {
+	case !s.primed[i]:
+		dst.CopyFrom(s.screenBuf)
+		s.primed[i] = true
+	default:
+		for _, r := range s.drawn[i] {
+			s.copyRect(dst, r)
+		}
+	}
+	s.drawn[i] = cur
+
+	damage := append(append([]rect(nil), s.shown...), cur...)
+	if s.fullDamage {
+		s.fullDamage = false
+		damage = []rect{{0, 0, dst.Width, dst.Height}}
+	}
+	s.shown = cur
+	return damage
+}
+
+func (s *SurfaceState) copyRect(dst *ShmBuffer, r rect) {
+	r = r.clip(min(dst.Width, s.screenBuf.Width), min(dst.Height, s.screenBuf.Height))
+	if r.w <= 0 || r.h <= 0 {
+		return
+	}
+	src := s.screenBuf
+	for y := r.y; y < r.y+r.h; y++ {
+		copy(dst.Data()[y*dst.Stride+r.x*4:][:r.w*4], src.Data()[y*src.Stride+r.x*4:][:r.w*4])
+	}
+}
+
+// Redraw draws the magnifier and preview at the pointer into the front buffer,
+// touching only the previous and new overlay areas; the rects are the damage.
+func (s *SurfaceState) Redraw() (*ShmBuffer, []rect) {
 	s.mu.Lock()
 	defer s.mu.Unlock()

 	if !s.readyForDisplay || s.screenBuf == nil {
-		return nil
+		return nil, nil
 	}

 	dst := s.renderBufs[s.front]
 	if dst == nil {
-		return nil
+		return nil, nil
 	}

-	dst.CopyFrom(s.screenBuf)
-
 	px := int(math.Round(float64(s.pointerX) * s.scaleX))
 	py := int(math.Round(float64(s.pointerY) * s.scaleY))

@@ -333,6 +390,8 @@ func (s *SurfaceState) Redraw() *ShmBuffer {
 	}

 	picked := GetPixelColorWithFormat(s.screenBuf, px, sampleY, s.screenFormat)
+	text := formatColorForPreview(picked, s.displayFormat, s.lowercase)
+	damage := s.restore(dst, []rect{magnifierRect(px, py), previewRect(dst.Width, dst.Height, px, py, text)})

 	drawMagnifierWithInversion(
 		dst.Data(), dst.Stride, dst.Width, dst.Height,
@@ -342,26 +401,25 @@ func (s *SurfaceState) Redraw() *ShmBuffer {

 	drawColorPreview(dst.Data(), dst.Stride, dst.Width, dst.Height, px, py, picked, s.displayFormat, s.lowercase, s.screenFormat)

-	return dst
+	return dst, damage
 }

 // RedrawScreenOnly renders just the screenshot without any overlay (magnifier, preview).
 // Used for when pointer leaves the surface.
-func (s *SurfaceState) RedrawScreenOnly() *ShmBuffer {
+func (s *SurfaceState) RedrawScreenOnly() (*ShmBuffer, []rect) {
 	s.mu.Lock()
 	defer s.mu.Unlock()

 	if !s.readyForDisplay || s.screenBuf == nil {
-		return nil
+		return nil, nil
 	}

 	dst := s.renderBufs[s.front]
 	if dst == nil {
-		return nil
+		return nil, nil
 	}

-	dst.CopyFrom(s.screenBuf)
-	return dst
+	return dst, s.restore(dst, nil)
 }

 func (s *SurfaceState) PickColor() (Color, bool) {
@@ -442,6 +500,8 @@ func blendColors(bg, fg Color, alpha float64) Color {
 	}
 }

+const magnifierRadius = 80
+
 func drawMagnifierWithInversion(
 	dst []byte, dstStride, dstW, dstH int,
 	src []byte, srcStride, srcW, srcH int,
@@ -455,7 +515,7 @@ func drawMagnifierWithInversion(
 	}

 	const (
-		outerRadius      = 80
+		outerRadius      = magnifierRadius
 		borderThickness  = 4
 		aaWidth          = 1.5
 		zoom             = 8.0
@@ -1065,30 +1125,28 @@ var fontGlyphs = map[rune][fontH]uint8{
 	},
 }

-func drawColorPreview(data []byte, stride, width, height int, cx, cy int, c Color, format OutputFormat, lowercase bool, pixelFormat PixelFormat) {
-	text := formatColorForPreview(c, format, lowercase)
+const (
+	previewPaddingX = 8
+	previewPaddingY = 4
+	previewSpace    = 2
+	previewOffset   = 88
+)
+
+// previewRect places the color label beside the magnifier, flipping to the left
+// and clamping so it stays on the buffer.
+func previewRect(width, height, cx, cy int, text string) rect {
 	if len(text) == 0 {
-		return
+		return rect{}
 	}
+	textW := len(text)*(fontW+previewSpace) - previewSpace
+	boxW := textW + previewPaddingX*2
+	boxH := fontH + previewPaddingY*2

-	const (
-		paddingX = 8
-		paddingY = 4
-		space    = 2
-		offset   = 88
-	)
-
-	textW := len(text)*(fontW+space) - space
-	textH := fontH
-
-	boxW := textW + paddingX*2
-	boxH := textH + paddingY*2
-
-	x := cx + offset
+	x := cx + previewOffset
 	y := cy - boxH/2

 	if x+boxW >= width {
-		x = cx - boxW - offset
+		x = cx - boxW - previewOffset
 	}
 	if x < 0 {
 		x = 0
@@ -1099,8 +1157,18 @@ func drawColorPreview(data []byte, stride, width, height int, cx, cy int, c Colo
 	if y+boxH >= height {
 		y = height - boxH
 	}
+	return rect{x, y, boxW, boxH}
+}

-	drawFilledRect(data, stride, width, height, x, y, boxW, boxH, c, pixelFormat)
+func drawColorPreview(data []byte, stride, width, height int, cx, cy int, c Color, format OutputFormat, lowercase bool, pixelFormat PixelFormat) {
+	text := formatColorForPreview(c, format, lowercase)
+	if len(text) == 0 {
+		return
+	}
+
+	box := previewRect(width, height, cx, cy, text)
+	x, y := box.x, box.y
+	drawFilledRect(data, stride, width, height, x, y, box.w, box.h, c, pixelFormat)

 	lum := 0.299*float64(c.R) + 0.587*float64(c.G) + 0.114*float64(c.B)
 	var fg Color
@@ -1109,7 +1177,7 @@ func drawColorPreview(data []byte, stride, width, height int, cx, cy int, c Colo
 	} else {
 		fg = Color{R: 255, G: 255, B: 255, A: 255}
 	}
-	drawText(data, stride, width, height, x+paddingX, y+paddingY, text, fg, pixelFormat)
+	drawText(data, stride, width, height, x+previewPaddingX, y+previewPaddingY, text, fg, pixelFormat)
 }

 func formatColorForPreview(c Color, format OutputFormat, lowercase bool) string {
@@ -196,13 +196,13 @@ func TestSurfaceState_PickColorNilBuffer(t *testing.T) {

 func TestSurfaceState_RedrawNilBuffer(t *testing.T) {
 	s := NewSurfaceState(FormatHex, false)
-	buf := s.Redraw()
+	buf, _ := s.Redraw()
 	assert.Nil(t, buf)
 }

 func TestSurfaceState_RedrawScreenOnlyNilBuffer(t *testing.T) {
 	s := NewSurfaceState(FormatHex, false)
-	buf := s.RedrawScreenOnly()
+	buf, _ := s.RedrawScreenOnly()
 	assert.Nil(t, buf)
 }

@@ -298,3 +298,99 @@ func TestBlendColors(t *testing.T) {
 	result = blendColors(bg, fg, 2.0)
 	assert.Equal(t, fg.R, result.R)
 }
+
+func newReadyState(t *testing.T, w, h int) *SurfaceState {
+	t.Helper()
+	s := NewSurfaceState(FormatHex, false)
+	if err := s.OnScreencopyBuffer(FormatXRGB8888, w, h, w*4+16); err != nil {
+		t.Fatal(err)
+	}
+	t.Cleanup(s.Destroy)
+	data := s.ScreenBuffer().Data()
+	for i := range data {
+		data[i] = byte(i*31 + i/7)
+	}
+	if err := s.OnLayerConfigure(w, h); err != nil {
+		t.Fatal(err)
+	}
+	s.OnScreencopyReady()
+	return s
+}
+
+func TestSurfaceState_RedrawIncremental(t *testing.T) {
+	const w, h = 400, 300
+	s := newReadyState(t, w, h)
+	screen := s.ScreenBuffer()
+
+	reference := func(px, py int, overlay bool) []byte {
+		ref, err := CreateShmBuffer(w, h, screen.Stride)
+		if err != nil {
+			t.Fatal(err)
+		}
+		defer ref.Close()
+		ref.CopyFrom(screen)
+		if overlay {
+			c := GetPixelColorWithFormat(screen, px, py, s.screenFormat)
+			drawMagnifierWithInversion(ref.Data(), ref.Stride, w, h, screen.Data(), screen.Stride, w, h, px, py, c, false, s.screenFormat)
+			drawColorPreview(ref.Data(), ref.Stride, w, h, px, py, c, FormatHex, false, s.screenFormat)
+		}
+		return append([]byte(nil), ref.Data()...)
+	}
+
+	inDamage := func(x, y int, damage []rect) bool {
+		for _, r := range damage {
+			if x >= r.x && x < r.x+r.w && y >= r.y && y < r.y+r.h {
+				return true
+			}
+		}
+		return false
+	}
+
+	var onScreen []byte
+	positions := [][2]int{{10, 10}, {200, 150}, {205, 152}, {399, 299}, {0, 299}, {-1, -1}, {120, 40}, {125, 40}, {300, 290}}
+	for i, pos := range positions {
+		hidden := pos[0] < 0
+		var buf *ShmBuffer
+		var damage []rect
+		px, py := pos[0], pos[1]
+		switch {
+		case hidden:
+			buf, damage = s.RedrawScreenOnly()
+		default:
+			s.OnPointerMotion(float64(px), float64(py))
+			buf, damage = s.Redraw()
+		}
+		if buf == nil {
+			t.Fatalf("step %d: no buffer", i)
+		}
+		want := reference(px, py, !hidden)
+		if !bytesEqual(buf.Data(), want) {
+			t.Fatalf("step %d: incremental frame differs from full render", i)
+		}
+		if onScreen != nil {
+			for y := range h {
+				for x := range w {
+					off := y*buf.Stride + x*4
+					if bytesEqual(want[off:off+4], onScreen[off:off+4]) || inDamage(x, y, damage) {
+						continue
+					}
+					t.Fatalf("step %d: pixel %d,%d changed outside damage %v", i, x, y, damage)
+				}
+			}
+		}
+		onScreen = want
+		s.SwapBuffers()
+	}
+}
+
+func bytesEqual(a, b []byte) bool {
+	if len(a) != len(b) {
+		return false
+	}
+	for i := range a {
+		if a[i] != b[i] {
+			return false
+		}
+	}
+	return true
+}