/*
* License Applicability. Except to the extent portions of this file are
* made subject to an alternative license as permitted in the SGI Free
* Software License B, Version 1.1 (the "License"), the contents of this
* file are subject only to the provisions of the License. You may not use
* this file except in compliance with the License. You may obtain a copy
* of the License at Silicon Graphics, Inc., attn: Legal Services, 1600
* Amphitheatre Parkway, Mountain View, CA 94043-1351, or at:
*
* http://oss.sgi.com/projects/FreeB
*
* Note that, as provided in the License, the Software is distributed on an
* "AS IS" basis, with ALL EXPRESS AND IMPLIED WARRANTIES AND CONDITIONS
* DISCLAIMED, INCLUDING, WITHOUT LIMITATION, ANY IMPLIED WARRANTIES AND
* CONDITIONS OF MERCHANTABILITY, SATISFACTORY QUALITY, FITNESS FOR A
* PARTICULAR PURPOSE, AND NON-INFRINGEMENT.
*
* Original Code. The Original Code is: OpenGL Sample Implementation,
* Version 1.2.1, released January 26, 2000, developed by Silicon Graphics,
* Inc. The Original Code is Copyright (c) 1991-2000 Silicon Graphics, Inc.
* Copyright in any portions created by third parties is as indicated
* elsewhere herein. All Rights Reserved.
*
* Additional Notice Provisions: The application programming interfaces
* established by SGI in conjunction with the Original Code are The
* OpenGL(R) Graphics System: A Specification (Version 1.2.1), released
* April 1, 1999; The OpenGL(R) Graphics System Utility Library (Version
* 1.3), released November 4, 1998; and OpenGL(R) Graphics with the X
* Window System(R) (Version 1.3), released October 19, 1998. This software
* was created using the OpenGL(R) version 1.2.1 Sample Implementation
* published by SGI, but has not been independently verified as being
* compliant with the OpenGL(R) version 1.2.1 Specification.
*
*/
/* mipmap.c
* 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.
*/
#include <GL/glut.h>
#include <stdlib.h>
GLubyte mipmapImage32[32][32][4];
GLubyte mipmapImage16[16][16][4];
GLubyte mipmapImage8[8][8][4];
GLubyte mipmapImage4[4][4][4];
GLubyte mipmapImage2[2][2][4];
GLubyte mipmapImage1[1][1][4];
#ifdef GL_VERSION_1_1
static GLuint texName;
#endif
void makeImages(void)
{
int i, j;
for (i = 0; i < 32; i++) {
for (j = 0; j < 32; j++) {
mipmapImage32[i][j][0] = 255;
mipmapImage32[i][j][1] = 255;
mipmapImage32[i][j][2] = 0;
mipmapImage32[i][j][3] = 255;
}
}
for (i = 0; i < 16; i++) {
for (j = 0; j < 16; j++) {
mipmapImage16[i][j][0] = 255;
mipmapImage16[i][j][1] = 0;
mipmapImage16[i][j][2] = 255;
mipmapImage16[i][j][3] = 255;
}
}
for (i = 0; i < 8; i++) {
for (j = 0; j < 8; j++) {
mipmapImage8[i][j][0] = 255;
mipmapImage8[i][j][1] = 0;
mipmapImage8[i][j][2] = 0;
mipmapImage8[i][j][3] = 255;
}
}
for (i = 0; i < 4; i++) {
for (j = 0; j < 4; j++) {
mipmapImage4[i][j][0] = 0;
mipmapImage4[i][j][1] = 255;
mipmapImage4[i][j][2] = 0;
mipmapImage4[i][j][3] = 255;
}
}
for (i = 0; i < 2; i++) {
for (j = 0; j < 2; j++) {
mipmapImage2[i][j][0] = 0;
mipmapImage2[i][j][1] = 0;
mipmapImage2[i][j][2] = 255;
mipmapImage2[i][j][3] = 255;
}
}
mipmapImage1[0][0][0] = 255;
mipmapImage1[0][0][1] = 255;
mipmapImage1[0][0][2] = 255;
mipmapImage1[0][0][3] = 255;
}
void init(void)
{
glEnable(GL_DEPTH_TEST);
glShadeModel(GL_FLAT);
glTranslatef(0.0, 0.0, -3.6);
makeImages();
glPixelStorei(GL_UNPACK_ALIGNMENT, 1);
#ifdef GL_VERSION_1_1
glGenTextures(1, &texName);
glBindTexture(GL_TEXTURE_2D, texName);
#endif
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_REPEAT);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_REPEAT);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_NEAREST);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER,
GL_NEAREST_MIPMAP_NEAREST);
glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA, 32, 32, 0,
GL_RGBA, GL_UNSIGNED_BYTE, mipmapImage32);
glTexImage2D(GL_TEXTURE_2D, 1, GL_RGBA, 16, 16, 0,
GL_RGBA, GL_UNSIGNED_BYTE, mipmapImage16);
glTexImage2D(GL_TEXTURE_2D, 2, GL_RGBA, 8, 8, 0,
GL_RGBA, GL_UNSIGNED_BYTE, mipmapImage8);
glTexImage2D(GL_TEXTURE_2D, 3, GL_RGBA, 4, 4, 0,
GL_RGBA, GL_UNSIGNED_BYTE, mipmapImage4);
glTexImage2D(GL_TEXTURE_2D, 4, GL_RGBA, 2, 2, 0,
GL_RGBA, GL_UNSIGNED_BYTE, mipmapImage2);
glTexImage2D(GL_TEXTURE_2D, 5, GL_RGBA, 1, 1, 0,
GL_RGBA, GL_UNSIGNED_BYTE, mipmapImage1);
glTexEnvf(GL_TEXTURE_ENV, GL_TEXTURE_ENV_MODE, GL_DECAL);
glEnable(GL_TEXTURE_2D);
}
void display(void)
{
glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
#ifdef GL_VERSION_1_1
glBindTexture(GL_TEXTURE_2D, texName);
#endif
glBegin(GL_QUADS);
glTexCoord2f(0.0, 0.0); glVertex3f(-2.0, -1.0, 0.0);
glTexCoord2f(0.0, 8.0); glVertex3f(-2.0, 1.0, 0.0);
glTexCoord2f(8.0, 8.0); glVertex3f(2000.0, 1.0, -6000.0);
glTexCoord2f(8.0, 0.0); glVertex3f(2000.0, -1.0, -6000.0);
glEnd();
glFlush();
}
void reshape(int w, int h)
{
glViewport(0, 0, (GLsizei) w, (GLsizei) h);
glMatrixMode(GL_PROJECTION);
glLoadIdentity();
gluPerspective(60.0, (GLfloat)w/(GLfloat)h, 1.0, 30000.0);
glMatrixMode(GL_MODELVIEW);
glLoadIdentity();
}
void keyboard (unsigned char key, int x, int y)
{
switch (key) {
case 27:
exit(0);
break;
default:
break;
}
}
int main(int argc, char** argv)
{
glutInit(&argc, argv);
glutInitDisplayMode (GLUT_SINGLE | GLUT_RGB | GLUT_DEPTH);
glutInitWindowSize (500, 500);
glutInitWindowPosition (50, 50);
glutCreateWindow (argv[0]);
init ();
glutDisplayFunc(display);
glutReshapeFunc(reshape);
glutKeyboardFunc(keyboard);
glutMainLoop();
return 0;
}