// All SWT widgets have helper methods to determine this so:
Control control=pane.getControl();
final Point drawLocation = control.toControl(getEvent().x, getEvent().y);
// By Adding a custom draw command we can draw on the viewport model...
pane.addDrawCommand(new AbstractDrawCommand(){
public Rectangle getValidArea() {
// I'm being lazy and returning null so that this will be re-drawn every time the
// Viewport is updated.
return null;