/* * 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 * Unpublished-- rights reserved under the copyright laws of the * United States.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. */ /* * MiniGL adaption by Hans-Joerg Frieden * December 1999 */ #include #include #include #include #include /* 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) { float array[] = { 0.0, 0.0, -2.0, -1.0, 0.0, 0.0, 1.0, -2.0, 1.0, 0.0, 1.0, 1.0, 0.0, 1.0, 0.0, 1.0, 0.0, 0.0, -1.0, 0.0, 0.0, 0.0, 1.0, -1.0, 0.0, 0.0, 1.0, 1.0, 1.0, 0.0, 1.0, 1.0, 2.41421, 1.0, -1.41421, 1.0, 0.0, 2.41421, -1.0, -1.41421 }; GLubyte index[] = { 4, 5, 6, 7, 0, 1, 2, 3 }; glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT); glEnable(GL_TEXTURE_2D); glTexEnvf(GL_TEXTURE_ENV, GL_TEXTURE_ENV_MODE, GL_REPLACE); glBindTexture(GL_TEXTURE_2D, texName); glInterleavedArrays(GL_T2F_V3F, 0, array); // glEnableClientState(GL_TEXTURE_COORD_ARRAY); // glEnableClientState(GL_VERTEX_ARRAY); // glDrawArrays(GL_QUADS, 0, 8); glDrawElements(GL_QUADS, 8, GL_UNSIGNED_BYTE, index); #if 0 glBegin(GL_QUADS); glArrayElement(0); glArrayElement(1); glArrayElement(2); glArrayElement(3); glArrayElement(4); glArrayElement(5); glArrayElement(6); glArrayElement(7); glEnd(); #endif glFlush(); glDisable(GL_TEXTURE_2D); mglUnlockDisplay(); mglSwitchDisplay(); } 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 */ static 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); 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); break; case 27: exit(0); break; default: break; } } static void idle(void) { display(); } int main(int argc, char *argv[]) { GLint width=640; GLint height=480; int i; for (i=1; i