package org.xmlvm.iphone.gl.nehelesson4;

import java.nio.FloatBuffer;

import org.xmlvm.iphone.CGRect;
import org.xmlvm.iphone.gl.BufferUtils;
import org.xmlvm.iphone.gl.GL;
import org.xmlvm.iphone.gl.GLView;

public class NeHeLesson4View extends GLView {
   private static final float TO_RADIANS = (3.14159f / 180.0f);
   
   private boolean viewSetup = false;
   private float zFar;
   private float fieldOfView;
   
   private float rtri = 0;
   private float rquad = 0;
   
   private FloatBuffer triVertices;
   private FloatBuffer triVertexColors;
   private FloatBuffer quadVertices;
   
   private float viewWidth;
   private float viewHeight;
   
   public NeHeLesson4View(CGRect rect) {
      super(rect);
   
      viewWidth = rect.size.width;
      viewHeight = rect.size.height;
      System.out.println("View: "+viewWidth+","+viewHeight);
      
               setOpaque(true);
               setClearsContextBeforeDrawing(false);
   }

   private void initViewGL() {
      System.out.println("Init view");
      triVertices = BufferUtils.createFloatBuffer(9);
      triVertexColors = BufferUtils.createFloatBuffer(12);
      quadVertices = BufferUtils.createFloatBuffer(12);
      
      triVertices.put(-1).put(-1).put(0.0f)
      .put(1).put(-1.0f).put(0.0f)
      .put(-1.0f).put(1.0f).put(0.0f);
      
      triVertexColors.put(1).put(0).put(0).put(1)
      .put(0).put(1).put(0).put(1)
      .put(0).put(0).put(1).put(1);
      
      quadVertices.put(-1).put(1).put(0)
      .put(1).put(1).put(0)
      .put(1).put(-1).put(0)
      .put(-1).put(-1).put(0);
      
      float zNear = 0.1f, 
      zFar = 1000.0f, 
      fieldOfView = 60.0f; 
      float size; 
      
      GL.glMatrixMode(GL.GL_PROJECTION); 
      size = zNear * (float) Math.tan((TO_RADIANS * fieldOfView) / 2.0); 
      GL.glLoadIdentity();
      GL.glFrustumf(-size, size, -size / (viewWidth / viewHeight), size / 
               (viewWidth / viewHeight), zNear, zFar); 
      
      GL.glViewport(0, 0, (int) viewWidth, (int) viewHeight); 
      GL.glMatrixMode(GL.GL_MODELVIEW); 
      GL.glLoadIdentity(); 
      GL.glClearColor(0.0f, 0.0f, 0.0f, 1.0f); 
   }
   
   @Override
   public void renderView() {
      if (!viewSetup) {
         viewSetup = true;
         initViewGL();
      }
      
      GL.glClear(GL.GL_COLOR_BUFFER_BIT);

      GL.glLoadIdentity(); 
      // Triangle
      GL.glTranslatef(-2.0f,1.0f,-6.0f);
      GL.glRotatef(rtri,0.0f,1.0f,0.0f);   
      GL.glEnableClientState(GL.GL_VERTEX_ARRAY);
      GL.glEnableClientState(GL.GL_COLOR_ARRAY);
      GL.glColorPointer (4, GL.GL_FLOAT, 0, triVertexColors);
      GL.glVertexPointer(3, GL.GL_FLOAT, 0, triVertices); 
      GL.glDrawArrays(GL.GL_TRIANGLE_STRIP, 0, 3);
      GL.glDisableClientState (GL.GL_COLOR_ARRAY);
      
      // Square
      GL.glLoadIdentity();
      GL.glColor4f(0.0f, 0.0f, 1.0f, 1.0f);
      GL.glTranslatef(2.0f,1.0f,-6.0f);
      GL.glRotatef(rquad,1.0f,0.0f,0.0f);
      GL.glVertexPointer(3, GL.GL_FLOAT, 0, quadVertices);
      GL.glDrawArrays(GL.GL_TRIANGLE_FAN, 0, 4); 
      GL.glDisableClientState(GL.GL_VERTEX_ARRAY);
      
      rtri += 1.5f;
      rquad -= 2.5f;
   }

}

Class clazz = loader.loadClass("mypackage.MyClass");
clazz.newInstance();