Method draw

src/org/opensourcephysics/display/Arrow.java:161–175

Draws the arrow. @param panel the drawing panel in which the arrow is viewed @param g the graphics context upon which to draw

(DrawingPanel panel, Graphics g)

   * @param g  the graphics context upon which to draw
   */
  @Override
public void draw(DrawingPanel panel, Graphics g) {
    Graphics2D g2 = (Graphics2D) g;
    AffineTransform tr = panel.getPixelTransform();
    g2.setPaint(color);
    // draw the shaft
    g2.draw(tr.createTransformedShape(new Line2D.Double(x, y, x+a, y+b)));
    ptA.setLocation(x+a, y+b);
    tr.transform(ptA, ptA);
    double aspect = panel.isSquareAspect() ? 1 : -tr.getScaleX()/tr.getScaleY();
    Shape temp = getHead(ptA, Math.atan2(b, aspect*a));
    // draw the head
    g2.fill(temp);
    g2.setPaint(Color.BLACK);
  }

  private double lastTheta = java.lang.Double.NaN, lastX, lastY, lastHeadSize;
  private Shape head;