package org.background.worker;

import java.util.Iterator;

import javax.swing.SwingWorker;

import org.background.LightProcessor;
import org.model.World;
import org.model.emitters.Emitter;
import org.model.emitters.Light;
import org.model.player.Player;
import org.newdawn.slick.Color;
import org.newdawn.slick.Graphics;
import org.newdawn.slick.Image;
/**
 * Shader, for lighting.
 * @author Senior
 */
public class Shader extends SwingWorker<World, Void> {

   private LightProcessor processor = null;
   
   public LightProcessor getProcessor() {
      return processor;
   }

   public void setProcessor(LightProcessor processor) {
      this.processor = processor;
   }

   public Shader(LightProcessor processor) {
      this.setProcessor(processor);
   }

   @Override
   protected World doInBackground() throws Exception {
      if(processor.getWorld() == null) 
          return null;
      World world = this.getProcessor().getWorld();
      Player player = world.getPlayer();
      if(player == null)
         return null;
      if(world.getLightEmitters().size() > 0) {
         for(Iterator<Emitter> it$ = world.getLightEmitters().descendingIterator(); it$.hasNext();) {
            Light l = (Light) it$.next();
            if(l == null)
               continue;
            if(!l.getPosition().isWithin(player.getPosition(), (int)l.getRange()))
               continue;
            if(player.getIcon() == null)
               continue;
            
            try {
               Image image = null;
               image = world.getBlank();
               if(image == null)
                  continue;
               image = image.getScaledCopy(player.getIcon().getWidth(), player.getIcon().getHeight());
               if(image == null)
                  continue;
               //Next line is problem line.
               Graphics g = image.getGraphics();
               if(g == null)
                  continue;
               Image pixel = null;
               
               for(int h = 0; h < player.getIcon().getHeight(); h++) {
                  for(int w = 0; w < player.getIcon().getWidth(); w++) {
                     pixel = player.getIcon().getSubImage(w, h, 1, 1);
                     g.drawImage(pixel, w, h, Color.red);
                  }
               }
               
               player.setIcon(image);
            } catch(Exception e) {
               e.printStackTrace();
            }
         }
      }
      return world;
   }
   
}

java.lang.NullPointerException
   at org.newdawn.slick.opengl.pbuffer.GraphicsFactory.init(GraphicsFactory.java:40)
   at org.newdawn.slick.opengl.pbuffer.GraphicsFactory.createGraphics(GraphicsFactory.java:120)
   at org.newdawn.slick.opengl.pbuffer.GraphicsFactory.getGraphicsForImage(GraphicsFactory.java:91)
   at org.newdawn.slick.Image.getGraphics(Image.java:397)
   at org.background.worker.Shader.doInBackground(Shader.java:62)
   at org.background.worker.Shader.doInBackground(Shader.java:1)
   at javax.swing.SwingWorker$1.call(Unknown Source)
   at java.util.concurrent.FutureTask$Sync.innerRun(Unknown Source)
   at java.util.concurrent.FutureTask.run(Unknown Source)
   at javax.swing.SwingWorker.run(Unknown Source)
   at org.background.LightProcessor.run(LightProcessor.java:37)
   at java.util.TimerThread.mainLoop(Unknown Source)
   at java.util.TimerThread.run(Unknown Source)

public World(Main main) {
      this.setMain(main);
      //Set up workers.
      this.setProcessor(new Processor(this));
      this.setLightProcessor(new LightProcessor(this));
      
      try {
         this.setBlank(new Image("./data/blank.png", false, Image.FILTER_LINEAR));
....
      } catch(SlickException e) {
         e.printStackTrace();
      }
   }