constructor

public Canvas() throws IOException {
    setDoubleBuffered(true);
    cursor = this.getMousePosition();
}
public GameCanvas() throws IOException {
    super();
    addMouseListener(prepareMouseInput());
}
public PaletteCanvas(int innerWidth_, int innerHeight_) throws IOException {
    super();
    innerWidth = innerWidth_;
    innerHeight = innerHeight_;
    addMouseListener(prepareMouseInput());
}