162 lines
4.1 KiB
C
162 lines
4.1 KiB
C
/*
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* (c) Copyright 1993, Silicon Graphics, Inc.
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* ALL RIGHTS RESERVED
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* Permission to use, copy, modify, and distribute this software for
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* any purpose and without fee is hereby granted, provided that the above
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* copyright notice appear in all copies and that both the copyright notice
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* and this permission notice appear in supporting documentation, and that
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* the name of Silicon Graphics, Inc. not be used in advertising
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* or publicity pertaining to distribution of the software without specific,
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* written prior permission.
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*
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* THE MATERIAL EMBODIED ON THIS SOFTWARE IS PROVIDED TO YOU "AS-IS"
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* AND WITHOUT WARRANTY OF ANY KIND, EXPRESS, IMPLIED OR OTHERWISE,
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* INCLUDING WITHOUT LIMITATION, ANY WARRANTY OF MERCHANTABILITY OR
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* FITNESS FOR A PARTICULAR PURPOSE. IN NO EVENT SHALL SILICON
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* GRAPHICS, INC. BE LIABLE TO YOU OR ANYONE ELSE FOR ANY DIRECT,
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* SPECIAL, INCIDENTAL, INDIRECT OR CONSEQUENTIAL DAMAGES OF ANY
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* KIND, OR ANY DAMAGES WHATSOEVER, INCLUDING WITHOUT LIMITATION,
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* LOSS OF PROFIT, LOSS OF USE, SAVINGS OR REVENUE, OR THE CLAIMS OF
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* THIRD PARTIES, WHETHER OR NOT SILICON GRAPHICS, INC. HAS BEEN
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* ADVISED OF THE POSSIBILITY OF SUCH LOSS, HOWEVER CAUSED AND ON
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* ANY THEORY OF LIABILITY, ARISING OUT OF OR IN CONNECTION WITH THE
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* POSSESSION, USE OR PERFORMANCE OF THIS SOFTWARE.
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*
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* US Government Users Restricted Rights
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* Use, duplication, or disclosure by the Government is subject to
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* restrictions set forth in FAR 52.227.19(c)(2) or subparagraph
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* (c)(1)(ii) of the Rights in Technical Data and Computer Software
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* clause at DFARS 252.227-7013 and/or in similar or successor
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* clauses in the FAR or the DOD or NASA FAR Supplement.
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* Unpublished-- rights reserved under the copyright laws of the
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* United States. Contractor/manufacturer is Silicon Graphics,
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* Inc., 2011 N. Shoreline Blvd., Mountain View, CA 94039-7311.
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*
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* OpenGL(TM) is a trademark of Silicon Graphics, Inc.
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*/
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#include <stdio.h>
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#include <string.h>
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#include <math.h>
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#include "tk.h"
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GLenum directRender;
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static void Init(void)
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{
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glClearColor(0.0, 0.0, 0.0, 0.0);
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glClearStencil(0);
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glStencilMask(1);
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glEnable(GL_STENCIL_TEST);
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}
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static void Reshape(int width, int height)
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{
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glViewport(0, 0, (GLint)width, (GLint)height);
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glMatrixMode(GL_PROJECTION);
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glLoadIdentity();
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glOrtho(-5.0, 5.0, -5.0, 5.0, -5.0, 5.0);
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glMatrixMode(GL_MODELVIEW);
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}
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static GLenum Key(int key, GLenum mask)
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{
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switch (key) {
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case TK_ESCAPE:
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tkQuit();
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}
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return GL_FALSE;
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}
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static void Draw(void)
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{
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glClear(GL_COLOR_BUFFER_BIT|GL_STENCIL_BUFFER_BIT);
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glStencilFunc(GL_ALWAYS, 1, 1);
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glStencilOp(GL_KEEP, GL_KEEP, GL_REPLACE);
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glColor3ub(200, 0, 0);
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glBegin(GL_POLYGON);
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glVertex3i(-4, -4, 0);
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glVertex3i( 4, -4, 0);
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glVertex3i( 0, 4, 0);
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glEnd();
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glStencilFunc(GL_EQUAL, 1, 1);
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glStencilOp(GL_INCR, GL_KEEP, GL_DECR);
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glColor3ub(0, 200, 0);
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glBegin(GL_POLYGON);
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glVertex3i(3, 3, 0);
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glVertex3i(-3, 3, 0);
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glVertex3i(-3, -3, 0);
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glVertex3i(3, -3, 0);
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glEnd();
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glStencilFunc(GL_EQUAL, 1, 1);
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glStencilOp(GL_KEEP, GL_KEEP, GL_KEEP);
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glColor3ub(0, 0, 200);
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glBegin(GL_POLYGON);
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glVertex3i(3, 3, 0);
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glVertex3i(-3, 3, 0);
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glVertex3i(-3, -3, 0);
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glVertex3i(3, -3, 0);
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glEnd();
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glFlush();
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}
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static GLenum Args(int argc, char **argv)
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{
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GLint i;
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directRender = GL_FALSE;
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for (i = 1; i < argc; i++) {
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if (strcmp(argv[i], "-dr") == 0) {
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directRender = GL_TRUE;
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} else if (strcmp(argv[i], "-ir") == 0) {
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directRender = GL_FALSE;
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} else {
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printf("%s (Bad option).\n", argv[i]);
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return GL_FALSE;
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}
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}
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return GL_TRUE;
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}
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void main(int argc, char **argv)
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{
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GLenum type;
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if (Args(argc, argv) == GL_FALSE) {
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tkQuit();
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}
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tkInitPosition(0, 0, 300, 300);
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type = TK_RGB | TK_SINGLE | TK_STENCIL;
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type |= (directRender) ? TK_DIRECT : TK_INDIRECT;
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tkInitDisplayMode(type);
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if (tkInitWindow("Stencil Test") == GL_FALSE) {
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tkQuit();
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}
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Init();
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tkExposeFunc(Reshape);
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tkReshapeFunc(Reshape);
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tkKeyDownFunc(Key);
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tkDisplayFunc(Draw);
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tkExec();
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}
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