Mouse input works

application.go

@@ -97,3 +97,8 @@ func (application *Application) Resized () (resized bool) {
 	resized = application.backend.Resized()
 	return
 }
+
+func (application *Application) MousePosition () (x, y int) {
+	x, y = application.backend.MousePosition()
+	return
+}

backend.go

@@ -14,6 +14,7 @@ type Backend interface {
 	Repeated      (button Button) (repeated bool)
 	Typed         () (text    string)
 	Resized       () (resized bool)
+	MousePosition () (x, y int)
 }
 
 type BackendFactory func (application *Application) (backend Backend, err error)

backends/pixel/pixel.go

@@ -126,6 +126,19 @@ func (backend *Backend) Resized () (resized bool) {
 	return
 }
 
+func (backend *Backend) MousePosition () (x, y int) {
+	vector := backend.window.MousePosition()
+	x = int (
+		(vector.X - float64(backend.metrics.paddingX)) /
+		float64(backend.metrics.cellWidth))
+	y = int (
+		(backend.windowBounds.Y -
+			vector.Y -
+			float64(backend.metrics.paddingY)) /
+		float64(backend.metrics.cellHeight))
+	return
+}
+
 func (backend *Backend) draw () {
 	// didDrawing := false
 	width, height := backend.application.Size()

buffer.go

@@ -65,6 +65,7 @@ func (buffer *Buffer) Size () (width, height int) {
 }
 
 func (buffer *Buffer) SetSize (width, height int) {
+	if width < 0 || height < 0 { return }
 	buffer.width   = width
 	buffer.height  = height
 	buffer.content = make([]Cell, width * height)
@@ -115,6 +116,7 @@ type DamageBuffer struct {
 }
 
 func (buffer *DamageBuffer) SetSize (width, height int) {
+	if width < 0 || height < 0 { return }
 	buffer.Buffer.SetSize(width, height)
 	buffer.clean = make([]bool, width * height)
 }

examples/hello/main.go

@@ -47,6 +47,12 @@ func run (application *stone.Application) {
 			application.Dot.X = 0
 			application.Dot.Y = 2
 			fmt.Fprintln(application, textBuffer)
+
+		}
+
+		if application.Pressed(stone.MouseButtonLeft) {
+			x, y := application.MousePosition()
+			application.SetRune(x, y, '#')
 		}
 		
 		if !application.Await(frameDelay) { break }