viewport.java

j3me java

  /*
  * J3DME Fast 3D software rendering for small devices
  * Copyright (C) 2001 Onno Hommes
  *
  * This library is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Lesser General Public
  * License as published by the Free Software Foundation; either
  * version 2.1 of the License, or (at your option) any later version.
  *
  * This library is distributed in the hope that it will be useful,
  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  * Lesser General Public License for more details.
  *
  * You should have received a copy of the GNU Lesser General Public
  * License along with this library; if not, write to the Free Software
  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  */

package net.jscience.j3dme;

/**
 * This class represents the viewport. The viewport is the connection
 * between the viewer and the camera. The viewport can be linked to one
 * camera at a time. It is like wiring your display to the specified
 * camera. By switching cameras you can quickly look forward or backward
 * or look into other virtual worlds.
 * @see Camera
 */
public class ViewPort{

    private Renderer renderer;
    protected Camera camera;
    protected int x,y,width,height;
    protected int cx,cy;
    private   int mx,my;

    /**
     * Return a ViewPort object<p>
     * The viewport needs a renderer to visualize the scene to the viewer,
     * and a camera. In addition you must specify the location and dimensions
     * of the viewport on your display. As part of the dimensions you must
     * specify if you need a border or not.
     *
     * @param   r The platform specific renderer object
     * @param   c The camera to look through
     * @param   xv The top left x coordinate of the viewport location
     * @param   yv The top left y coordinate of the viewport location
     * @param   wv The width of the viewport
     * @param   hv The height of the viewport
     * @param   border The border indicator
     * @return A viewport with the supplied specifications.
     */
    public ViewPort(Renderer r,Camera c,int xv,int yv,int wv,int hv){
     // Initialize ViewPort parameters
     renderer = r;
     camera = c;
     x = xv;
     y = yv;
     width = wv;
     height = hv;

      // Determine 2D coordinate origin
     mx = x + width;
     my = y + height;
     cx = mx/2;
     cy = my/2;
    }

    /**
     * Render the current camera view onto the displau<p>
     * This method will display the scene visible through the current
     * attached camera.
     */
    public void renderScene(){     renderer.drawScene(this);    }

    /**
     * Return the current attached camera<p>
     * @return The camera attached to the viewport.
     */
    public Camera getCamera()
    {
     return camera;
    }

    /**
     * Attach a new camera to the viewport<p>
     * @param   c The new camera object
     */
    public void setCamera(Camera c)
    {
     camera = c;
    }
}