MidArrowLineStyle.java

/*
 * Copyright (c) 2016 Vivid Solutions.
 *
 * All rights reserved. This program and the accompanying materials
 * are made available under the terms of the Eclipse Public License 2.0
 * and Eclipse Distribution License v. 1.0 which accompanies this distribution.
 * The Eclipse Public License is available at http://www.eclipse.org/legal/epl-v20.html
 * and the Eclipse Distribution License is available at
 *
 * http://www.eclipse.org/org/documents/edl-v10.php.
 */

package org.locationtech.jtstest.testbuilder.ui.style;

import java.awt.Color;
import java.awt.Graphics2D;
import java.awt.geom.GeneralPath;
import java.awt.geom.NoninvertibleTransformException;
import java.awt.geom.Point2D;

import org.locationtech.jtstest.testbuilder.ui.Viewport;


public class MidArrowLineStyle 
  extends SegmentStyle
{
  private final static double HEAD_ANGLE = 30;
  private final static double HEAD_LENGTH = 10;

  private Color color = Color.RED;

  public MidArrowLineStyle(Color color) {
    this.color = color;
  }

  protected void paint(int index, Point2D p0, Point2D p1, int lineType, Viewport vp, Graphics2D gr)
  throws Exception
  {
  	paintMidpointArrow(p0, p1, vp, gr);
  }

  protected void paintMidpointArrow(Point2D p0, Point2D p1, Viewport viewport,
      Graphics2D graphics) throws NoninvertibleTransformException 
  {
    // can't compute valid arrow for zero-length segments
    if (p0.equals(p1)) {
      return;
    }
    graphics.setColor(color);
    //      graphics.setStroke(1.0);
    Point2D mid = new Point2D.Float((float) ((p0.getX() + p1.getX()) / 2),
        (float) ((p0.getY() + p1.getY()) / 2));
    GeneralPath arrowhead = ArrowLineEndStyle.arrowheadPath(p0, p1, mid,
    		HEAD_LENGTH, HEAD_ANGLE);
    graphics.draw(arrowhead);
  }


}