/*
 *  mipmap.java
 *  This program demonstrates using mipmaps for texture maps.
 *  To overtly show the effect of mipmaps, each mipmap reduction
 *  level has a solidly colored, contrasting texture image.
 *  Thus, the quadrilateral which is drawn is drawn with several
 *  different colors.
 */

import java.awt.Frame;
import java.io.IOException;
import java.lang.String;
import java.lang.System;

import jgl.GL;
import jgl.GLCanvas;

public class mipmap extends GLCanvas {

    private byte mipmapImage32 [][][] = new byte [32][32][3];
    private byte mipmapImage16 [][][] = new byte [16][16][3];
    private byte mipmapImage8 [][][] = new byte [8][8][3];
    private byte mipmapImage4 [][][] = new byte [4][4][3];
    private byte mipmapImage2 [][][] = new byte [2][2][3];
    private byte mipmapImage1 [][][] = new byte [1][1][3];

    private void makeImages () {
    	int i, j;

	for (i = 0; i < 32; i++) {
	    for (j = 0; j < 32; j++) {
		mipmapImage32 [i][j][0] = (byte)255;
		mipmapImage32 [i][j][1] = (byte)255;
		mipmapImage32 [i][j][2] = (byte)0;
	    }
	}
	for (i = 0; i < 16; i++) {
	    for (j = 0; j < 16; j++) {
		mipmapImage16 [i][j][0] = (byte)255;
		mipmapImage16 [i][j][1] = (byte)0;
		mipmapImage16 [i][j][2] = (byte)255;
	    }
	}
	for (i = 0; i < 8; i++) {
	    for (j = 0; j < 8; j++) {
		mipmapImage8 [i][j][0] = (byte)255;
		mipmapImage8 [i][j][1] = (byte)0;
		mipmapImage8 [i][j][2] = (byte)0;
	    }
	}
	for (i = 0; i < 4; i++) {
	    for (j = 0; j < 4; j++) {
		mipmapImage4 [i][j][0] = (byte)0;
		mipmapImage4 [i][j][1] = (byte)255;
		mipmapImage4 [i][j][2] = (byte)0;
	    }
	}
	for (i = 0; i < 2; i++) {
	    for (j = 0; j < 2; j++) {
		mipmapImage2 [i][j][0] = (byte)0;
		mipmapImage2 [i][j][1] = (byte)0;
		mipmapImage2 [i][j][2] = (byte)255;
	    }
	}
	mipmapImage1 [0][0][0] = (byte)255;
	mipmapImage1 [0][0][1] = (byte)255;
	mipmapImage1 [0][0][2] = (byte)255;
    }

    private void myinit () {
	myGL.glEnable (GL.GL_DEPTH_TEST);
	myGL.glDepthFunc (GL.GL_LESS);
	myGL.glShadeModel (GL.GL_FLAT);

	myGL.glTranslatef (0.0f, 0.0f, -3.6f);
	makeImages ();
	myGL.glPixelStorei (GL.GL_UNPACK_ALIGNMENT, 1);
	myGL.glTexImage2D (GL.GL_TEXTURE_2D, 0, 3, 32, 32, 0,
		GL.GL_RGB, GL.GL_UNSIGNED_BYTE, mipmapImage32);
	myGL.glTexImage2D (GL.GL_TEXTURE_2D, 1, 3, 16, 16, 0,
		GL.GL_RGB, GL.GL_UNSIGNED_BYTE, mipmapImage16);
	myGL.glTexImage2D (GL.GL_TEXTURE_2D, 2, 3, 8, 8, 0,
		GL.GL_RGB, GL.GL_UNSIGNED_BYTE, mipmapImage8);
	myGL.glTexImage2D (GL.GL_TEXTURE_2D, 3, 3, 4, 4, 0,
		GL.GL_RGB, GL.GL_UNSIGNED_BYTE, mipmapImage4);
	myGL.glTexImage2D (GL.GL_TEXTURE_2D, 4, 3, 2, 2, 0,
		GL.GL_RGB, GL.GL_UNSIGNED_BYTE, mipmapImage2);
	myGL.glTexImage2D (GL.GL_TEXTURE_2D, 5, 3, 1, 1, 0,
		GL.GL_RGB, GL.GL_UNSIGNED_BYTE, mipmapImage1);
	myGL.glTexParameterf (GL.GL_TEXTURE_2D, GL.GL_TEXTURE_WRAP_S,
		GL.GL_REPEAT);
	myGL.glTexParameterf (GL.GL_TEXTURE_2D, GL.GL_TEXTURE_WRAP_T,
		GL.GL_REPEAT);
	myGL.glTexParameterf (GL.GL_TEXTURE_2D, GL.GL_TEXTURE_MAG_FILTER,
		GL.GL_NEAREST);
	myGL.glTexParameterf (GL.GL_TEXTURE_2D, GL.GL_TEXTURE_MIN_FILTER,
		GL.GL_NEAREST_MIPMAP_NEAREST);
	myGL.glTexEnvf (GL.GL_TEXTURE_ENV, GL.GL_TEXTURE_ENV_MODE, GL.GL_DECAL);
	myGL.glEnable (GL.GL_TEXTURE_2D);
    }

    public void display () {
	myGL.glClear (GL.GL_COLOR_BUFFER_BIT | GL.GL_DEPTH_BUFFER_BIT);
	myGL.glBegin (GL.GL_QUADS);
	myGL.glTexCoord2f (0.0f, 0.0f);
	myGL.glVertex3f (-2.0f, -1.0f, 0.0f);
	myGL.glTexCoord2f (0.0f, 8.0f);
	myGL.glVertex3f (-2.0f, 1.0f, 0.0f);
	myGL.glTexCoord2f (8.0f, 8.0f);
	myGL.glVertex3f (2000.0f, 1.0f, -6000.0f);
	myGL.glTexCoord2f (8.0f, 0.0f);
	myGL.glVertex3f (2000.0f, -1.0f, -6000.0f);
	myGL.glEnd ();
	myGL.glFlush ();
    }

    public void myReshape (int w, int h) {
        myGL.glViewport (0, 0, w, h);
        myGL.glMatrixMode (GL.GL_PROJECTION);
        myGL.glLoadIdentity ();
	myGLU.gluPerspective (60.0, 1.0 * (double)w/(double)h, 1.0, 30000.0);
        myGL.glMatrixMode (GL.GL_MODELVIEW);
        myGL.glLoadIdentity ();
    }

    public void keyboard (char key, int x, int y) {
	switch (key) {
	    case 27:
		System.exit(0);
	    default:
		break;
	}
    }

    public void init () {
	myUT.glutInitWindowSize (500, 500);
	myUT.glutInitWindowPosition (0, 0);
	myUT.glutCreateWindow (this);
	myinit ();
	myUT.glutReshapeFunc ("myReshape");
	myUT.glutDisplayFunc ("display");
	myUT.glutKeyboardFunc ("keyboard");
	myUT.glutMainLoop ();
    }

    static public void main (String args[]) throws IOException {
	Frame mainFrame = new Frame ();
	mainFrame.setSize (508, 527);
	mipmap mainCanvas = new mipmap ();
	mainCanvas.init();
	mainFrame.add (mainCanvas);
	mainFrame.setVisible (true);
    }

}