automated snapshot

sketch.go

@@ -90,22 +90,28 @@ func (s *Sketch) AddColorLayer(name string, c rl.Color) {
 	s.AddLayer(name, colorLayer)
 }
 
-func (s *Sketch) Draw(ctx *RenderCtx) {
+func (s *Sketch) Redraw(ctx *RenderCtx) {
 	// render onto all layer textures
 	for _, instance := range s.layerToolsOrdered {
 		layer := instance.layer
-		layer.Update(ctx)
-		if instance.layer.IsDirty() {
-			rl.BeginTextureMode(instance.texture)
-			rl.PushMatrix()
-			layer.Draw(ctx)
-			rl.PopMatrix()
-			rl.EndTextureMode()
+		// ignore this layer entirely unless it's visible
+		if instance.config.visible {
+			layer.Update(ctx)
+			// re-render to texture if dirty
+			if instance.layer.IsDirty() {
+				rl.BeginTextureMode(instance.texture)
+				rl.PushMatrix()
+				layer.Draw(ctx)
+				rl.PopMatrix()
+				rl.EndTextureMode()
+			}
 		}
 	}
+}
 
-	// composite all layers to screen
+func (s *Sketch) Draw(ctx *RenderCtx) {
 
+	s.Redraw(ctx)
 
 	// copy from full texture for compositing, with vertical flipping
 	src := rl.Rectangle {
@@ -122,7 +128,6 @@ func (s *Sketch) Draw(ctx *RenderCtx) {
 	viewport := s.CalcViewport(ctx)
 
 	rl.BeginTextureMode(s.composite)
-	//rl.ClearBackground(rl.Black)
 	for _, instance := range s.layerToolsOrdered {
 		config := instance.config
 		if config.visible {