io/pointer: added CursorNameOp

The cursor can now be customized for a given area.

Signed-off-by: pierre <pierre.curto@gmail.com>

io/pointer/pointer.go

@@ -49,6 +49,11 @@ type AreaOp struct {
 	rect image.Rectangle
 }
 
+// CursorNameOp sets the cursor for the current area.
+type CursorNameOp struct {
+	Name CursorName
+}
+
 // InputOp declares an input handler ready for pointer
 // events.
 type InputOp struct {
@@ -178,6 +183,11 @@ func (op AreaOp) Add(o *op.Ops) {
 	bo.PutUint32(data[14:], uint32(op.rect.Max.Y))
 }
 
+func (op CursorNameOp) Add(o *op.Ops) {
+	data := o.Write1(opconst.TypeCursorLen, op.Name)
+	data[0] = byte(opconst.TypeCursor)
+}
+
 func (h InputOp) Add(o *op.Ops) {
 	data := o.Write1(opconst.TypePointerInputLen, h.Tag)
 	data[0] = byte(opconst.TypePointerInput)