| /* |
| * Copyright (c) 1991, 1992, 1993 Silicon Graphics, Inc. |
| * |
| * Permission to use, copy, modify, distribute, and sell this software and |
| * its documentation for any purpose is hereby granted without fee, provided |
| * that (i) the above copyright notices and this permission notice appear in |
| * all copies of the software and related documentation, and (ii) the name of |
| * Silicon Graphics may not be used in any advertising or |
| * publicity relating to the software without the specific, prior written |
| * permission of Silicon Graphics. |
| * |
| * THE SOFTWARE IS PROVIDED "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 BE LIABLE FOR |
| * ANY SPECIAL, INCIDENTAL, INDIRECT OR CONSEQUENTIAL DAMAGES OF ANY KIND, |
| * OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, |
| * WHETHER OR NOT ADVISED OF THE POSSIBILITY OF DAMAGE, AND ON ANY THEORY OF |
| * LIABILITY, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE |
| * OF THIS SOFTWARE. |
| */ |
| |
| #include <stdio.h> |
| #include <stdlib.h> |
| #include <string.h> |
| #include <math.h> |
| #include <GL/glut.h> |
| |
| |
| static void Init(void) |
| { |
| glShadeModel(GL_FLAT); |
| glClearColor(0.0, 0.0, 0.0, 0.0); |
| |
| glClearStencil(0); |
| glStencilMask(1); |
| glEnable(GL_STENCIL_TEST); |
| } |
| |
| static void Reshape(int width, int height) |
| { |
| |
| glViewport(0, 0, (GLint)width, (GLint)height); |
| |
| glMatrixMode(GL_PROJECTION); |
| glLoadIdentity(); |
| glOrtho(-5.0, 5.0, -5.0, 5.0, -5.0, 5.0); |
| glMatrixMode(GL_MODELVIEW); |
| } |
| |
| static void Key(unsigned char key, int x, int y) |
| { |
| |
| switch (key) { |
| case 27: |
| exit(1); |
| } |
| } |
| |
| static void Draw(void) |
| { |
| |
| glClear(GL_COLOR_BUFFER_BIT|GL_STENCIL_BUFFER_BIT); |
| |
| glStencilFunc(GL_ALWAYS, 1, 1); |
| glStencilOp(GL_KEEP, GL_KEEP, GL_REPLACE); |
| |
| glColor3ub(200, 0, 0); |
| glBegin(GL_POLYGON); |
| glVertex3i(-4, -4, 0); |
| glVertex3i( 4, -4, 0); |
| glVertex3i( 0, 4, 0); |
| glEnd(); |
| |
| glStencilFunc(GL_EQUAL, 1, 1); |
| glStencilOp(GL_INCR, GL_KEEP, GL_DECR); |
| |
| glColor3ub(0, 200, 0); |
| glBegin(GL_POLYGON); |
| glVertex3i(3, 3, 0); |
| glVertex3i(-3, 3, 0); |
| glVertex3i(-3, -3, 0); |
| glVertex3i(3, -3, 0); |
| glEnd(); |
| |
| glStencilFunc(GL_EQUAL, 1, 1); |
| glStencilOp(GL_KEEP, GL_KEEP, GL_KEEP); |
| |
| glColor3ub(0, 0, 200); |
| glBegin(GL_POLYGON); |
| glVertex3i(3, 3, 0); |
| glVertex3i(-3, 3, 0); |
| glVertex3i(-3, -3, 0); |
| glVertex3i(3, -3, 0); |
| glEnd(); |
| |
| glFlush(); |
| } |
| |
| static GLenum Args(int argc, char **argv) |
| { |
| GLint i; |
| |
| |
| for (i = 1; i < argc; i++) { |
| if (strcmp(argv[i], "-dr") == 0) { |
| } else { |
| printf("%s (Bad option).\n", argv[i]); |
| return GL_FALSE; |
| } |
| } |
| return GL_TRUE; |
| } |
| |
| int main(int argc, char **argv) |
| { |
| GLenum type; |
| |
| glutInit(&argc, argv); |
| |
| if (Args(argc, argv) == GL_FALSE) { |
| exit(1); |
| } |
| |
| glutInitWindowPosition(0, 0); glutInitWindowSize( 300, 300); |
| |
| type = GLUT_RGB | GLUT_SINGLE | GLUT_STENCIL; |
| glutInitDisplayMode(type); |
| |
| if (glutCreateWindow("Stencil Test") == GL_FALSE) { |
| exit(1); |
| } |
| |
| Init(); |
| |
| glutReshapeFunc(Reshape); |
| glutKeyboardFunc(Key); |
| glutDisplayFunc(Draw); |
| glutMainLoop(); |
| return 0; |
| } |