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Diffstat (limited to 'progs/redbook/checker.c')
| -rw-r--r-- | progs/redbook/checker.c | 140 |
1 files changed, 140 insertions, 0 deletions
diff --git a/progs/redbook/checker.c b/progs/redbook/checker.c new file mode 100644 index 00000000000..06cbae7dd7e --- /dev/null +++ b/progs/redbook/checker.c @@ -0,0 +1,140 @@ + +/* 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 + * Unpublished-- rights reserved under the copyright laws of the + * United States.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. + */ +/* checker.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. + */ +#include <stdlib.h> +#include <GL/glut.h> + +/* Create checkerboard texture */ +#define checkImageWidth 64 +#define checkImageHeight 64 +GLubyte checkImage[checkImageWidth][checkImageHeight][3]; + +void makeCheckImage(void) +{ + int i, j, c; + + for (i = 0; i < checkImageWidth; i++) { + for (j = 0; j < checkImageHeight; 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; + } + } +} + +void myinit(void) +{ + glClearColor (0.0, 0.0, 0.0, 0.0); + glEnable(GL_DEPTH_TEST); + glDepthFunc(GL_LESS); + + makeCheckImage(); + glPixelStorei(GL_UNPACK_ALIGNMENT, 1); + glTexImage2D(GL_TEXTURE_2D, 0, 3, checkImageWidth, + checkImageHeight, 0, GL_RGB, GL_UNSIGNED_BYTE, + &checkImage[0][0][0]); + glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP); + glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP); + glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR); + glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR); + glTexEnvf(GL_TEXTURE_ENV, GL_TEXTURE_ENV_MODE, GL_DECAL); + glEnable(GL_TEXTURE_2D); + glShadeModel(GL_FLAT); +} + +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, 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(); + glutSwapBuffers(); +} + +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, 30.0); + glMatrixMode(GL_MODELVIEW); + glLoadIdentity(); + glTranslatef(0.0, 0.0, -3.6); +} + +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_DOUBLE | GLUT_RGB | GLUT_DEPTH); + glutCreateWindow("checker"); + myinit(); + glutReshapeFunc (myReshape); + glutDisplayFunc(display); + glutKeyboardFunc(key); + glutMainLoop(); + return 0; /* ANSI C requires main to return int. */ +} |