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Diffstat (limited to 'progs/redbook/texsub.c')
-rw-r--r-- | progs/redbook/texsub.c | 187 |
1 files changed, 187 insertions, 0 deletions
diff --git a/progs/redbook/texsub.c b/progs/redbook/texsub.c new file mode 100644 index 00000000000..5dc36ec4e7c --- /dev/null +++ b/progs/redbook/texsub.c @@ -0,0 +1,187 @@ +/* + * Copyright (c) 1993-1997, 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 + * Unpublished-- rights reserved under the copyright laws of the + * United States.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(R) is a registered trademark of Silicon Graphics, Inc. + */ + +/* texsub.c + * This program texture maps a checkerboard image onto + * two rectangles. This program clamps the texture, if + * the texture coordinates fall outside 0.0 and 1.0. + * If the s key is pressed, a texture subimage is used to + * alter the original texture. If the r key is pressed, + * the original texture is restored. + */ +#include <GL/glut.h> +#include <stdlib.h> +#include <stdio.h> + +#ifdef GL_VERSION_1_1 +/* Create checkerboard textures */ +#define checkImageWidth 64 +#define checkImageHeight 64 +#define subImageWidth 16 +#define subImageHeight 16 +static GLubyte checkImage[checkImageHeight][checkImageWidth][4]; +static GLubyte subImage[subImageHeight][subImageWidth][4]; + +static GLuint texName; + +void makeCheckImages(void) +{ + int i, j, c; + + for (i = 0; i < checkImageHeight; i++) { + for (j = 0; j < checkImageWidth; j++) { + c = ((((i&0x8)==0)^((j&0x8))==0))*255; + checkImage[i][j][0] = (GLubyte) c; + checkImage[i][j][1] = (GLubyte) c; + checkImage[i][j][2] = (GLubyte) c; + checkImage[i][j][3] = (GLubyte) 255; + } + } + for (i = 0; i < subImageHeight; i++) { + for (j = 0; j < subImageWidth; j++) { + c = ((((i&0x4)==0)^((j&0x4))==0))*255; + subImage[i][j][0] = (GLubyte) c; + subImage[i][j][1] = (GLubyte) 0; + subImage[i][j][2] = (GLubyte) 0; + subImage[i][j][3] = (GLubyte) 255; + } + } +} + +void init(void) +{ + glClearColor (0.0, 0.0, 0.0, 0.0); + glShadeModel(GL_FLAT); + glEnable(GL_DEPTH_TEST); + + makeCheckImages(); + glPixelStorei(GL_UNPACK_ALIGNMENT, 1); + + glGenTextures(1, &texName); + glBindTexture(GL_TEXTURE_2D, texName); + + 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); + glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA, checkImageWidth, checkImageHeight, + 0, GL_RGBA, GL_UNSIGNED_BYTE, checkImage); +} + +void display(void) +{ + glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT); + glEnable(GL_TEXTURE_2D); + glTexEnvf(GL_TEXTURE_ENV, GL_TEXTURE_ENV_MODE, GL_DECAL); + glBindTexture(GL_TEXTURE_2D, texName); + glBegin(GL_QUADS); + glTexCoord2f(0.0, 0.0); glVertex3f(-2.0, -1.0, 0.0); + glTexCoord2f(0.0, 1.0); glVertex3f(-2.0, 1.0, 0.0); + glTexCoord2f(1.0, 1.0); glVertex3f(0.0, 1.0, 0.0); + glTexCoord2f(1.0, 0.0); glVertex3f(0.0, -1.0, 0.0); + + glTexCoord2f(0.0, 0.0); glVertex3f(1.0, -1.0, 0.0); + glTexCoord2f(0.0, 1.0); glVertex3f(1.0, 1.0, 0.0); + glTexCoord2f(1.0, 1.0); glVertex3f(2.41421, 1.0, -1.41421); + glTexCoord2f(1.0, 0.0); glVertex3f(2.41421, -1.0, -1.41421); + glEnd(); + glFlush(); + glDisable(GL_TEXTURE_2D); +} + +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, 30.0); + glMatrixMode(GL_MODELVIEW); + glLoadIdentity(); + glTranslatef(0.0, 0.0, -3.6); +} + +/* ARGSUSED1 */ +void keyboard (unsigned char key, int x, int y) +{ + switch (key) { + case 's': + case 'S': + glBindTexture(GL_TEXTURE_2D, texName); + glTexSubImage2D(GL_TEXTURE_2D, 0, 12, 44, subImageWidth, + subImageHeight, GL_RGBA, + GL_UNSIGNED_BYTE, subImage); + glutPostRedisplay(); + break; + case 'r': + case 'R': + glBindTexture(GL_TEXTURE_2D, texName); + glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA, checkImageWidth, + checkImageHeight, 0, GL_RGBA, + GL_UNSIGNED_BYTE, checkImage); + glutPostRedisplay(); + break; + case 27: + exit(0); + break; + default: + break; + } +} + +int main(int argc, char** argv) +{ + glutInit(&argc, argv); + glutInitDisplayMode(GLUT_SINGLE | GLUT_RGB | GLUT_DEPTH); + glutInitWindowSize(250, 250); + glutInitWindowPosition(100, 100); + glutCreateWindow(argv[0]); + init(); + glutDisplayFunc(display); + glutReshapeFunc(reshape); + glutKeyboardFunc(keyboard); + glutMainLoop(); + return 0; +} +#else +int main(int argc, char** argv) +{ + fprintf (stderr, "This program demonstrates a feature which is not in OpenGL Version 1.0.\n"); + fprintf (stderr, "If your implementation of OpenGL Version 1.0 has the right extensions,\n"); + fprintf (stderr, "you may be able to modify this program to make it run.\n"); + return 0; +} +#endif |