Resize canvas when the window is resized

backends/x/x.go

@@ -1,7 +1,6 @@
 package x
 
 import "image"
-import "image/color"
 // import "golang.org/x/image/font"
 // import "golang.org/x/image/font/basicfont"
 
@@ -91,11 +90,52 @@ func (backend *Backend) handleXEvent (event xgb.Event) {
 		backend.metrics.windowHeight = newHeight
 
 		if sizeChanged {
-			// TODO: resize and rebind canvas
+			// compress events
+			configureEvent =
+				backend.compressConfigureNotify(configureEvent)
+		
+			// resize and rebind canvas
+			backend.canvas.Destroy()
+			backend.canvas = xgraphics.New (
+				backend.connection,
+				image.Rect (
+					0, 0,
+					backend.metrics.windowWidth,
+					backend.metrics.windowHeight))
+			// FIXME (?): this doesn't work. if it were to work, it
+			// would possibly be a cleaner way to resize the canvas.
+			// backend.canvas.Scale (
+				// backend.metrics.windowWidth,
+				// backend.metrics.windowHeight)
+			backend.bindCanvas()
 		}
 	}
 }
 
+func (backend *Backend) compressConfigureNotify (
+	firstEvent xproto.ConfigureNotifyEvent,
+) (
+	lastEvent xproto.ConfigureNotifyEvent,
+) {
+	backend.connection.Sync()
+	xevent.Read(backend.connection, false)
+	lastEvent = firstEvent
+	
+	for index, untypedEvent := range xevent.Peek(backend.connection) {
+		if untypedEvent.Err != nil { continue }
+		
+		typedEvent, ok := untypedEvent.Event.(xproto.ConfigureNotifyEvent)
+		if !ok { continue }
+
+		lastEvent = typedEvent
+		defer func (index int) {
+			xevent.DequeueAt(backend.connection, index)
+		} (index)
+	}
+
+	return
+}
+
 func (backend *Backend) shutDown () {
 	backend.channel <- stone.EventQuit { }
 }
@@ -160,10 +200,6 @@ func factory (application *stone.Application) (output stone.Backend, err error)
 			0, 0,
 			backend.metrics.windowWidth,
 			backend.metrics.windowHeight))
-
-	for i := 8; i < 64; i ++ {
-		backend.canvas.Set(8, i, color.RGBA { R: 0xFF, A: 0xFF })
-	}
 	backend.bindCanvas()
 
 	// attatch graceful close handler