package com.example.openGLDem;

import java.nio.ByteBuffer;
import java.nio.ByteOrder;
import java.nio.FloatBuffer;
import java.nio.ShortBuffer;

import javax.microedition.khronos.opengles.GL10;

import android.content.Context;

//filename: SimpleTriangleRenderer.java
public class CarreRenderer extends AbstractRenderer
{
   //Number of points or vertices we want to use
    private final static int VERTS = 4;
    
    //A raw native buffer to hold the point coordinates
    private FloatBuffer mFVertexBuffer;
    
    private FloatBuffer mFColorBuffer;
    
    //A raw native buffer to hold indices
    //allowing a reuse of points.
    private ShortBuffer mIndexBuffer;
    
    public CarreRenderer(Context context) 
    {
        float[] vertices = {
        		  -0.5f, 0.5f, 0.0f,
        	        -0.5f,-0.5f,0.0f,
        	        0.5f,-0.5f,0.0f,
        	        0.5f,0.5f,0.0f
        };
        
        float colors[] = {
                0.0f,  1.0f,  0.0f,  1.0f,
                0.0f,  1.0f,  1.0f,  1f,
                1f,  1.0f,  1f,  1.0f,
                0.0f,  1.0f,  0.0f,  1.0f
             };
     
        short[] indices = {
        		0,1,2,
        		0,2,3};
        
   
        
        ByteBuffer vbb = ByteBuffer.allocateDirect(vertices.length * 4); //1 float= 4 octets
        vbb.order(ByteOrder.nativeOrder());
        mFVertexBuffer = vbb.asFloatBuffer();
        mFVertexBuffer.put(vertices);
        mFVertexBuffer.position(0);
        
        ByteBuffer cbb = ByteBuffer.allocateDirect(colors.length * 4); //1 float= 4 octets
        cbb.order(ByteOrder.nativeOrder());
        mFColorBuffer = cbb.asFloatBuffer();
        mFColorBuffer.put(colors);
        mFColorBuffer.position(0);
        
        ByteBuffer ibb = ByteBuffer.allocateDirect(indices.length* 2);
        ibb.order(ByteOrder.nativeOrder());
        mIndexBuffer = ibb.asShortBuffer();
        mIndexBuffer.put(indices);  
        mIndexBuffer.position(0);
    }

   //overriden method
    protected void draw(GL10 gl)
    {
    	gl.glColorPointer(4, GL10.GL_FLOAT, 0, mFColorBuffer);
        gl.glVertexPointer(3, GL10.GL_FLOAT, 0, mFVertexBuffer);
        gl.glDrawElements(GL10.GL_TRIANGLES, 6,
                 GL10.GL_UNSIGNED_SHORT, mIndexBuffer);
        
        
    }
}