Method handleMouseEvent

core/src/processing/core/PApplet.java:2279–2386

Actually take action based on a mouse event. Internally updates mouseX, mouseY, mousePressed, and mouseEvent. Then it calls the event type with no params, i.e. mousePressed() or mouseReleased() that the user may have overloaded to do something more useful.

(MouseEvent event)

   * overloaded to do something more useful.
   */
  protected void handleMouseEvent(MouseEvent event) {
    // https://processing.org/bugs/bugzilla/170.html
    // also prevents mouseExited() on the mac from hosing the mouse
    // position, because x/y are bizarre values on the exit event.
    // see also the id check below... both of these go together.
    // Not necessary to set mouseX/Y on RELEASE events because the
    // actual position will have been set by a PRESS or DRAG event.
    // However, PRESS events might come without a preceding move,
    // if the sketch window gains focus on that PRESS.
    final int action = event.getAction();
    if (action == MouseEvent.DRAG ||
        action == MouseEvent.MOVE ||
        action == MouseEvent.PRESS) {
      pmouseX = emouseX;
      pmouseY = emouseY;
      if (windowRatio) {
        rmouseX = floor((event.getX() - ratioLeft) / ratioScale);
        rmouseY = floor((event.getY() - ratioTop) / ratioScale);
      }
      mouseX = event.getX();
      mouseY = event.getY();
    }

    int button = event.getButton();

    // If running on macOS, allow ctrl-click as right mouse click.
    // Handled inside PApplet so that the same logic need not be redone
    // for each Surface independently, since the code seems to be identical:
    // no native code backing Surface objects (AWT, JavaFX, JOGL) handle it.
    if (PApplet.platform == PConstants.MACOS &&
        button == PConstants.LEFT) {
      if (action == MouseEvent.PRESS && event.isControlDown()) {
        // The ctrl key may only be down during the press, but we need to store
        // it so that the drag or release still is considered a right-click.
        macosCtrlClick = true;
      }
      if (macosCtrlClick) {
        button = PConstants.RIGHT;
        // Recreate the Event object as a right-click, and unset the CTRL flag,
        // since it's not a ctrl-right-click, it's just a right click.
        int modifiers = event.getModifiers() & ~Event.CTRL;
        event = new MouseEvent(event.getNative(), event.getMillis(),
                               event.getAction(), modifiers,
                               event.getX(), event.getY(),
                               button, event.getCount());
      }
      if (action == MouseEvent.CLICK) {
        // Un-set the variable for the next time around.
        // (This won't affect the current event being handled.)
        // Changed to CLICK instead of RELEASE for 4.0a6, because the click
        // event will fire after the press/drag/release events have fired.
        macosCtrlClick = false;
      }
    }

    // Get the (already processed) button code
    mouseButton = button;