Class DrawableBuffer

src/org/opensourcephysics/display/DrawableBuffer.java:26–235

A DrawableBuffer contains an image of drawable objects. This image is displayed on a drawing panel whenever when the draw method is invoked. A drawble buffer should be used to render complex drawable objects that change infrequently. Use the updateImage method to generate a new image when the prop

 * @version 1.0
 */
public class DrawableBuffer implements Drawable, Measurable {
  Image image;
  boolean invalid = true;
  ArrayList<Drawable> drawableList = new ArrayList<Drawable>(); // list of Drawable objects
  Color background = Color.white;
  boolean measured = false;
  double xmin, xmax, ymin, ymax;
  boolean visible = true;

  /**
   * Constructor DrawableBuffer
   *
   */
  public DrawableBuffer() {}

  /**
   * Constructor DrawableBuffer
   *
   * @param drawable
   */
  public DrawableBuffer(Drawable drawable) {
    addDrawable(drawable);
  }

  /**
   * Adds a drawable object to the drawing buffer.
   * @param drawable
   */
  public synchronized void addDrawable(Drawable drawable) {
    if(!drawableList.contains(drawable)) {
      drawableList.add(drawable);
    }
    invalidateImage();
  }

  /**
   * Method setBackground
   *
   * @param color
   */
  public void setBackground(Color color) {
    background = color;
  }

  /**
   * Sets the bufferrer's visible flag.
   * @param vis boolean
   */
  public void setVisible(boolean vis) {
    visible = vis;
  }

  /**
   * Reads the visible flag.
   * @return boolean
   */
  public boolean isVisible() {
    return visible;