diff --git a/main.go b/main.go
index 191d4e9..5677a3c 100644
--- a/main.go
+++ b/main.go
@@ -15,21 +15,21 @@ import (
 const (
 	targetWidth  = 1000
 	targetHeight = 1000
-	sourceScale  = 8
+	sourceScale  = 2
 	snapshotsDir = "snapshots"
 )
 
 type TextureCam struct {
-	SourceWidth  int
-	SourceHeight int
+	SourceWidth  int32
+	SourceHeight int32
 	LookAt       rl.Vector2
 	Zoom         float32
 }
 
 func main() {
 
-	sourceWidth := sourceScale * targetWidth
-	sourceHeight := sourceScale * targetHeight
+	sourceWidth := int32(sourceScale * targetWidth)
+	sourceHeight := int32(sourceScale * targetHeight)
 
 	os.MkdirAll(snapshotsDir, 0755)
 	log := log.New(os.Stdout, "", log.Ldate|log.Ltime|log.Lshortfile)
@@ -64,7 +64,7 @@ func main() {
 			x: -float32(sourceWidth / 2.0),
 			y: -float32(sourceHeight / 2.0),
 			field: &ScaleField{
-				scale: 5.0,
+				scale: 1.0,
 				field: &imageField,
 			},
 		}
@@ -72,7 +72,7 @@ func main() {
 
 	contourLayer := NewContourLayer(rng, &field, sourceWidth, sourceHeight)
 
-	sketch := NewSketch()
+	sketch := NewSketch(sourceWidth, sourceHeight)
 	//sketch.CreateLayer("testPattern", &TestPattern{}, int32(sourceWidth), int32(sourceHeight))
 	//sketch.CreateLayer("actors", &contourLayer, int32(sourceWidth), int32(sourceHeight))
 	//sketch.CreateLayer("field", &FieldLayer{field: &field, dirty: true}, int32(sourceWidth), int32(sourceHeight))
@@ -112,7 +112,9 @@ func main() {
 		sketch.Draw(renderCtx)
 
 		if rl.IsKeyDown(rl.KeySpace) {
-			if _, err := storage.Save(); err != nil {
+			capture := sketch.Capture()
+
+			if _, err := storage.Save(capture); err != nil {
 				log.Printf("Error saving snapshot: %v\n", err)
 			}
 		}
@@ -172,11 +174,11 @@ type ContourLayer struct {
 	field                     Field
 	actors                    []*Actor
 	rng                       *rand.Rand
-	sourceWidth int
-	sourceHeight int
+	sourceWidth int32
+	sourceHeight int32
 }
 
-func NewContourLayer(rng *rand.Rand, field Field, sourceWidth int, sourceHeight int) ContourLayer {
+func NewContourLayer(rng *rand.Rand, field Field, sourceWidth int32, sourceHeight int32) ContourLayer {
 
 	actors := make([]*Actor, 0)
 
@@ -195,8 +197,8 @@ func NewContourLayer(rng *rand.Rand, field Field, sourceWidth int, sourceHeight
 
 func (s *ContourLayer) AddActors(n int) {
 	for range n {
-		x := s.rng.Int() % s.sourceWidth
-		y := s.rng.Int() % s.sourceHeight
+		x := s.rng.Int31() % s.sourceWidth
+		y := s.rng.Int31() % s.sourceHeight
 		newActor :=
 			&Actor {
 				position: rl.Vector2{X: float32(x), Y: float32(y)},
diff --git a/sketch.go b/sketch.go
index 7e6f020..f2c0583 100644
--- a/sketch.go
+++ b/sketch.go
@@ -6,14 +6,20 @@ import (
 )
 
 type Sketch struct {
+	sourceWidth int32
+	sourceHeight int32
 	layerTools map[string]LayerTools
 	layerToolsOrdered []LayerTools
+	composite rl.RenderTexture2D
 }
 
-func NewSketch() Sketch {
-	return Sketch{
+func NewSketch(sourceWidth, sourceHeight int32) Sketch {
+	return Sketch {
+		sourceWidth: sourceWidth,
+		sourceHeight: sourceHeight,
 		layerTools: make(map[string]LayerTools),
 		layerToolsOrdered: []LayerTools {},
+		composite: rl.LoadRenderTexture(sourceWidth, sourceHeight),
 	}
 }
 
@@ -49,12 +55,28 @@ func (s *Sketch) Draw(ctx *RenderCtx) {
 		Height: float32(ctx.TargetHeight),
 	}
 
-	viewport := s.CalcViewport(ctx)
-
-	for _, instance := range s.layerToolsOrdered {
-		rl.DrawTexturePro(instance.texture.Texture, viewport, screen, rl.Vector2{}, 0, rl.White)
+	// copy from full texture for compositing, with vertical flipping
+	src := rl.Rectangle {
+		X: 0, Y: 0,
+		Width: float32(ctx.SourceWidth),
+		Height: -float32(ctx.SourceHeight),
+	}
+	dst := rl.Rectangle {
+		X: 0, Y: 0,
+		Width: float32(ctx.SourceWidth),
+		Height: float32(ctx.SourceHeight),
 	}
 
+	viewport := s.CalcViewport(ctx)
+
+	rl.BeginTextureMode(s.composite)
+	rl.ClearBackground(rl.Black)
+	for _, instance := range s.layerToolsOrdered {
+		rl.DrawTexturePro(instance.texture.Texture, src, dst, rl.Vector2{}, 0, rl.White)
+	}
+	rl.EndTextureMode()
+
+	rl.DrawTexturePro(s.composite.Texture, viewport, screen, rl.Vector2{}, 0, rl.White)
 }
 
 func (s *Sketch) CalcViewport(ctx *RenderCtx) rl.Rectangle {
@@ -98,6 +120,24 @@ func (s *Sketch) Update(ctx *RenderCtx) {
 
 }
 
+type SketchCapture struct {
+	compositeImage *rl.Image
+	layerImages []*rl.Image
+}
+
+func (s *Sketch) Capture() *SketchCapture {
+	composite := rl.LoadImageFromTexture(s.composite.Texture)
+	layerImages := make([]*rl.Image, len(s.layerToolsOrdered))
+	for i, layerTool := range s.layerToolsOrdered {
+		layerImages[i] = rl.LoadImageFromTexture(layerTool.texture.Texture)
+	}
+	return &SketchCapture {
+		compositeImage: composite,
+		layerImages: layerImages,
+	}
+}
+
+
 type LayerTools struct {
 	name    string
 	layer   Layer
diff --git a/storage.go b/storage.go
index e069750..85bda3e 100644
--- a/storage.go
+++ b/storage.go
@@ -85,18 +85,29 @@ func initSchema(db *sql.DB) error {
 	return tx.Commit()
 }
 
-func (s *Storage) Save() (string, error) {
+func (s *Storage) Save(capture *SketchCapture) (string, error) {
 	id, _ := s.gen.Next()
 	kid := ids.Base62Encode(id)
 	path := filepath.Join(s.snapshotsDir, kid)
 	os.MkdirAll(path, 0755)
 
+	// wysiwyg at screen res
 	img := rl.LoadImageFromScreen()
 	defer rl.UnloadImage(img)
 
 	snapshotPng := filepath.Join(path, fmt.Sprintf("%s.png", kid))
 	rl.ExportImage(*img, snapshotPng)
 
+	// capture full res compsite
+	compositePng := filepath.Join(path, fmt.Sprintf("%s-composite.png", kid))
+	rl.ExportImage(*capture.compositeImage, compositePng)
+
+	// capture full res layer
+	for i, layerImage := range capture.layerImages {
+		layerPng := filepath.Join(path, fmt.Sprintf("%s-%3d.png", kid, i))
+		rl.ExportImage(*layerImage, layerPng)
+	}
+
 	s.log.Printf("Checking git status...\n")
 
 	hash, branch, committed, err := CommitAllIfDirty(s.repoRoot, "automated snapshot", s.log)