package edu.cs4730.OpenGlDemo;

import javax.microedition.khronos.egl.EGLConfig;
import javax.microedition.khronos.opengles.GL10;


import android.opengl.GLU;
import android.opengl.GLSurfaceView.Renderer;

public class OpenGLRenderer implements Renderer {

	// Initialize our square.
	Square square = new Square();

	/*
	 * (non-Javadoc)
	 *
	 * @see
	 * android.opengl.GLSurfaceView.Renderer#onSurfaceCreated(javax.
         * microedition.khronos.opengles.GL10, javax.microedition.khronos.
         * egl.EGLConfig)
	 */
	public void onSurfaceCreated(GL10 gl, EGLConfig config) {
		// Set the background color to black ( rgba ).
		gl.glClearColor(0.0f, 0.0f, 0.0f, 0.5f);  // OpenGL docs.
		// Enable Smooth Shading, default not really needed.
		gl.glShadeModel(GL10.GL_SMOOTH);// OpenGL docs.
		// Depth buffer setup.
		gl.glClearDepthf(1.0f);// OpenGL docs.
		// Enables depth testing.
		gl.glEnable(GL10.GL_DEPTH_TEST);// OpenGL docs.
		// The type of depth testing to do.
		gl.glDepthFunc(GL10.GL_LEQUAL);// OpenGL docs.
		// Really nice perspective calculations.
		gl.glHint(GL10.GL_PERSPECTIVE_CORRECTION_HINT, // OpenGL docs.
                          GL10.GL_NICEST);
	}

	/*
	 * (non-Javadoc)
	 *
	 * @see
	 * android.opengl.GLSurfaceView.Renderer#onDrawFrame(javax.
         * microedition.khronos.opengles.GL10)
	 */
	public void onDrawFrame(GL10 gl) {
		// Clears the screen and depth buffer.
		gl.glClear(GL10.GL_COLOR_BUFFER_BIT | // OpenGL docs.
                           GL10.GL_DEPTH_BUFFER_BIT);
		// Replace the current matrix with the identity matrix
		gl.glLoadIdentity(); // OpenGL docs

		// Translates 4 units into the screen.
		gl.glTranslatef(0, 0, -4); // OpenGL docs

		// Draw our square.
		square.draw(gl); // ( NEW )
		

	}

	/*
	 * (non-Javadoc)
	 *
	 * @see
	 * android.opengl.GLSurfaceView.Renderer#onSurfaceChanged(javax.
         * microedition.khronos.opengles.GL10, int, int)
	 */
	public void onSurfaceChanged(GL10 gl, int width, int height) {
		// Sets the current view port to the new size.
		gl.glViewport(0, 0, width, height);// OpenGL docs.
		// Select the projection matrix
		gl.glMatrixMode(GL10.GL_PROJECTION);// OpenGL docs.
		// Reset the projection matrix
		gl.glLoadIdentity();// OpenGL docs.
		// Calculate the aspect ratio of the window
		GLU.gluPerspective(gl, 45.0f, (float) width / (float) height,
        0.1f, 100.0f);
		// Select the modelview matrix
		gl.glMatrixMode(GL10.GL_MODELVIEW);// OpenGL docs.
		// Reset the modelview matrix
		gl.glLoadIdentity();// OpenGL docs.
	}
}

