Buffer, DamageBuffer, and Application are io.Writers

backends/pixel/pixel.go

@@ -19,6 +19,7 @@ type Backend struct {
 	backgroundStamper *imdraw.IMDraw
 	fontAtlas         *text.Atlas
 	textDrawer        *text.Text
+	showBounds        bool
 
 	metrics struct {
 		cellWidth  int
@@ -176,15 +177,18 @@ func (backend *Backend) draw () {
 			backend.textDrawer.Draw(backend.window, pixel.IM)
 		}
 	}
-	
-	backend.backgroundStamper.Clear()
-	backend.backgroundStamper.Color =
-		backend.config.Color(stone.ColorBackground)
-	backend.backgroundStamper.Push (
-		backend.vectorAtPosition(0, 0),
-		backend.vectorAtPosition(width, height))
-	backend.backgroundStamper.Rectangle(1)
-	backend.backgroundStamper.Draw(backend.window)
+
+	// draw a rectangle around the buffer if we are showing bounds
+	if backend.showBounds {
+		backend.backgroundStamper.Clear()
+		backend.backgroundStamper.Color =
+			backend.config.Color(stone.ColorBackground)
+		backend.backgroundStamper.Push (
+			backend.vectorAtPosition(0, 0),
+			backend.vectorAtPosition(width, height))
+		backend.backgroundStamper.Rectangle(1)
+		backend.backgroundStamper.Draw(backend.window)
+	}
 
 	backend.window.SwapBuffers()
 }