Home | History | Annotate | Download | only in light 
      1 /*
      2  * Copyright (c) 2009-2010 jMonkeyEngine
      3  * All rights reserved.
      4  *
      5  * Redistribution and use in source and binary forms, with or without
      6  * modification, are permitted provided that the following conditions are
      7  * met:
      8  *
      9  * * Redistributions of source code must retain the above copyright
     10  *   notice, this list of conditions and the following disclaimer.
     11  *
     12  * * Redistributions in binary form must reproduce the above copyright
     13  *   notice, this list of conditions and the following disclaimer in the
     14  *   documentation and/or other materials provided with the distribution.
     15  *
     16  * * Neither the name of 'jMonkeyEngine' nor the names of its contributors
     17  *   may be used to endorse or promote products derived from this software
     18  *   without specific prior written permission.
     19  *
     20  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
     21  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
     22  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
     23  * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR
     24  * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
     25  * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
     26  * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
     27  * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
     28  * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
     29  * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
     30  * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
     31  */
     32 
     33 package com.jme3.light;
     34 
     35 import com.jme3.export.InputCapsule;
     36 import com.jme3.export.JmeExporter;
     37 import com.jme3.export.JmeImporter;
     38 import com.jme3.export.OutputCapsule;
     39 import com.jme3.math.Vector3f;
     40 import com.jme3.scene.Spatial;
     41 import java.io.IOException;
     42 
     43 /**
     44  * <code>DirectionalLight</code> is a light coming from a certain direction in world space.
     45  * E.g sun or moon light.
     46  * <p>
     47  * Directional lights have no specific position in the scene, they always
     48  * come from their direction regardless of where an object is placed.
     49  */
     50 public class DirectionalLight extends Light {
     51 
     52     protected Vector3f direction = new Vector3f(0f, -1f, 0f);
     53 
     54     @Override
     55     public void computeLastDistance(Spatial owner) {
     56         lastDistance = 0; // directional lights are always closest to their owner
     57     }
     58 
     59     /**
     60      * Returns the direction vector of the light.
     61      *
     62      * @return The direction vector of the light.
     63      *
     64      * @see DirectionalLight#setDirection(com.jme3.math.Vector3f)
     65      */
     66     public Vector3f getDirection() {
     67         return direction;
     68     }
     69 
     70     /**
     71      * Sets the direction of the light.
     72      * <p>
     73      * Represents the vector direction the light is coming from.
     74      * (1, 0, 0) would represent a directional light coming from the X axis.
     75      *
     76      * @param dir the direction of the light.
     77      */
     78     public void setDirection(Vector3f dir){
     79         direction.set(dir);
     80         if (!direction.isUnitVector()) {
     81             direction.normalizeLocal();
     82         }
     83     }
     84 
     85     @Override
     86     public Type getType() {
     87         return Type.Directional;
     88     }
     89 
     90     @Override
     91     public void write(JmeExporter ex) throws IOException {
     92         super.write(ex);
     93         OutputCapsule oc = ex.getCapsule(this);
     94         oc.write(direction, "direction", null);
     95     }
     96 
     97     @Override
     98     public void read(JmeImporter im) throws IOException {
     99         super.read(im);
    100         InputCapsule ic = im.getCapsule(this);
    101         direction = (Vector3f) ic.readSavable("direction", null);
    102     }
    103 
    104 }
    105