OpenGLUT 0.6.3 development - OpenGLUT: mipmap.c File Reference
Keywords: OpenGLUT, FreeGLUT, OpenGL, GLUT, X11, Windows, Programming, Documentation, Download, Development, Sourceforge

OpenGLUT Documentation
Introduction | Documentation | Examples | Proposals | Authors | Copying | Todo | Bugs | Links

# mipmap.c File Reference

## Detailed Description

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.

    /* Copyright (c) Mark J. Kilgard, 1994. */

    /*
     * (c) Copyright 1993, Silicon Graphics, Inc.
     * ALL RIGHTS RESERVED
     * Permission to use, copy, modify, and distribute this software for
     * any purpose and without fee is hereby granted, provided that the above
     * copyright notice appear in all copies and that both the copyright notice
     * and this permission notice appear in supporting documentation, and that
     * the name of Silicon Graphics, Inc. not be used in advertising
     * or publicity pertaining to distribution of the software without specific,
     * written prior permission.
     *
     * THE MATERIAL EMBODIED ON THIS SOFTWARE IS PROVIDED TO YOU "AS-IS"
     * AND WITHOUT WARRANTY OF ANY KIND, EXPRESS, IMPLIED OR OTHERWISE,
     * INCLUDING WITHOUT LIMITATION, ANY WARRANTY OF MERCHANTABILITY OR
     * FITNESS FOR A PARTICULAR PURPOSE.  IN NO EVENT SHALL SILICON
     * GRAPHICS, INC.  BE LIABLE TO YOU OR ANYONE ELSE FOR ANY DIRECT,
     * SPECIAL, INCIDENTAL, INDIRECT OR CONSEQUENTIAL DAMAGES OF ANY
     * KIND, OR ANY DAMAGES WHATSOEVER, INCLUDING WITHOUT LIMITATION,
     * LOSS OF PROFIT, LOSS OF USE, SAVINGS OR REVENUE, OR THE CLAIMS OF
     * THIRD PARTIES, WHETHER OR NOT SILICON GRAPHICS, INC.  HAS BEEN
     * ADVISED OF THE POSSIBILITY OF SUCH LOSS, HOWEVER CAUSED AND ON
     * ANY THEORY OF LIABILITY, ARISING OUT OF OR IN CONNECTION WITH THE
     * POSSESSION, USE OR PERFORMANCE OF THIS SOFTWARE.
     *
     * US Government Users Restricted Rights
     * Use, duplication, or disclosure by the Government is subject to
     * restrictions set forth in FAR 52.227.19(c)(2) or subparagraph
     * (c)(1)(ii) of the Rights in Technical Data and Computer Software
     * clause at DFARS 252.227-7013 and/or in similar or successor
     * clauses in the FAR or the DOD or NASA FAR Supplement.
     * Unpublished-- rights reserved under the copyright laws of the
     * United States.  Contractor/manufacturer is Silicon Graphics,
     * Inc., 2011 N.  Shoreline Blvd., Mountain View, CA 94039-7311.
     *
     * OpenGL(TM) is a trademark of Silicon Graphics, Inc.
     */

    #include <GL/openglut.h>
    #include <stdlib.h>

    GLubyte mipmapImage32[32][32][3];
    GLubyte mipmapImage16[16][16][3];
    GLubyte mipmapImage8[8][8][3];
    GLubyte mipmapImage4[4][4][3];
    GLubyte mipmapImage2[2][2][3];
    GLubyte mipmapImage1[1][1][3];

    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;
        }
        }
        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;
        }
        }
        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;
        }
        }
        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;
        }
        }
        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;
        }
        }
        mipmapImage1[0][0][0] = 255;
        mipmapImage1[0][0][1] = 255;
        mipmapImage1[0][0][2] = 255;
    }

    void myinit(void)
    {
        glEnable(GL_DEPTH_TEST);
        glDepthFunc(GL_LESS);
        glShadeModel(GL_FLAT);

        glTranslatef(0.0, 0.0, -3.6);
        makeImages();
        glPixelStorei(GL_UNPACK_ALIGNMENT, 1);
        glTexImage2D(GL_TEXTURE_2D, 0, 3, 32, 32, 0,
             GL_RGB, GL_UNSIGNED_BYTE, &mipmapImage32[0][0][0]);
        glTexImage2D(GL_TEXTURE_2D, 1, 3, 16, 16, 0,
             GL_RGB, GL_UNSIGNED_BYTE, &mipmapImage16[0][0][0]);
        glTexImage2D(GL_TEXTURE_2D, 2, 3, 8, 8, 0,
             GL_RGB, GL_UNSIGNED_BYTE, &mipmapImage8[0][0][0]);
        glTexImage2D(GL_TEXTURE_2D, 3, 3, 4, 4, 0,
             GL_RGB, GL_UNSIGNED_BYTE, &mipmapImage4[0][0][0]);
        glTexImage2D(GL_TEXTURE_2D, 4, 3, 2, 2, 0,
             GL_RGB, GL_UNSIGNED_BYTE, &mipmapImage2[0][0][0]);
        glTexImage2D(GL_TEXTURE_2D, 5, 3, 1, 1, 0,
             GL_RGB, GL_UNSIGNED_BYTE, &mipmapImage1[0][0][0]);
        glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_REPEAT);
        glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_REPEAT);
        glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_NEAREST);
        glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER,
        GL_NEAREST_MIPMAP_NEAREST);
        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);
        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 myReshape(int w, int h)
    {
        glViewport(0, 0, w, h);
        glMatrixMode(GL_PROJECTION);
        glLoadIdentity();
        gluPerspective(60.0, 1.0*(GLfloat)w/(GLfloat)h, 1.0, 30000.0);
        glMatrixMode(GL_MODELVIEW);
        glLoadIdentity();
    }

    static void
    key(unsigned char k, int x, int y)
    {
      switch (k) {
      case 27:  /* Escape */
        exit(0);
        break;
      default:
        return;
      }
      glutPostRedisplay();
    }

    int main(int argc, char** argv)
    {
        glutInit(&argc, argv);
        glutInitDisplayMode (GLUT_SINGLE | GLUT_RGB | GLUT_DEPTH);
        glutInitWindowSize (500, 500);
        glutCreateWindow (argv[0]);
        myinit();
        glutReshapeFunc (myReshape);
        glutDisplayFunc(display);
        glutKeyboardFunc(key);
        glutMainLoop();
        return 0;             /* ANSI C requires main to return int. */
    }

OpenGLUT Development @ Sourceforge
Homepage | Summary | Files | CVS | Forums | Lists | Bugs | RFE
Generated on Tue Oct 5 18:44:23 2004 for OpenGLUT by doxygen 1.3.8
The OpenGLUT project is hosted by sourceforge.net.