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Diffstat (limited to 'progs/redbook/alpha3D.c')
-rw-r--r-- | progs/redbook/alpha3D.c | 175 |
1 files changed, 175 insertions, 0 deletions
diff --git a/progs/redbook/alpha3D.c b/progs/redbook/alpha3D.c new file mode 100644 index 00000000000..413836edd5b --- /dev/null +++ b/progs/redbook/alpha3D.c @@ -0,0 +1,175 @@ +/* + * 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 + * Unpublished-- rights reserved under the copyright laws of the + * United States.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. + */ + +/* + * alpha3D.c + * This program demonstrates how to intermix opaque and + * alpha blended polygons in the same scene, by using + * glDepthMask. Press the 'a' key to animate moving the + * transparent object through the opaque object. Press + * the 'r' key to reset the scene. + */ +#include <stdlib.h> +#include <stdio.h> +#include <GL/glut.h> + +#define MAXZ 8.0 +#define MINZ -8.0 +#define ZINC 0.4 + +static float solidZ = MAXZ; +static float transparentZ = MINZ; +static GLuint sphereList, cubeList; + +static void init(void) +{ + GLfloat mat_specular[] = { 1.0, 1.0, 1.0, 0.15 }; + GLfloat mat_shininess[] = { 100.0 }; + GLfloat position[] = { 0.5, 0.5, 1.0, 0.0 }; + + glMaterialfv(GL_FRONT, GL_SPECULAR, mat_specular); + glMaterialfv(GL_FRONT, GL_SHININESS, mat_shininess); + glLightfv(GL_LIGHT0, GL_POSITION, position); + + glEnable(GL_LIGHTING); + glEnable(GL_LIGHT0); + glEnable(GL_DEPTH_TEST); + + sphereList = glGenLists(1); + glNewList(sphereList, GL_COMPILE); + glutSolidSphere (0.4, 16, 16); + glEndList(); + + cubeList = glGenLists(1); + glNewList(cubeList, GL_COMPILE); + glutSolidCube (0.6); + glEndList(); +} + +void display(void) +{ + GLfloat mat_solid[] = { 0.75, 0.75, 0.0, 1.0 }; + GLfloat mat_zero[] = { 0.0, 0.0, 0.0, 1.0 }; + GLfloat mat_transparent[] = { 0.0, 0.8, 0.8, 0.6 }; + GLfloat mat_emission[] = { 0.0, 0.3, 0.3, 0.6 }; + + glClear (GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT); + + glPushMatrix (); + glTranslatef (-0.15, -0.15, solidZ); + glMaterialfv(GL_FRONT, GL_EMISSION, mat_zero); + glMaterialfv(GL_FRONT, GL_DIFFUSE, mat_solid); + glCallList (sphereList); + glPopMatrix (); + + glPushMatrix (); + glTranslatef (0.15, 0.15, transparentZ); + glRotatef (15.0, 1.0, 1.0, 0.0); + glRotatef (30.0, 0.0, 1.0, 0.0); + glMaterialfv(GL_FRONT, GL_EMISSION, mat_emission); + glMaterialfv(GL_FRONT, GL_DIFFUSE, mat_transparent); + glEnable (GL_BLEND); + glDepthMask (GL_FALSE); + glBlendFunc (GL_SRC_ALPHA, GL_ONE); + glCallList (cubeList); + glDepthMask (GL_TRUE); + glDisable (GL_BLEND); + glPopMatrix (); + + glutSwapBuffers(); +} + +void reshape(int w, int h) +{ + glViewport(0, 0, (GLint) w, (GLint) h); + glMatrixMode(GL_PROJECTION); + glLoadIdentity(); + if (w <= h) + glOrtho (-1.5, 1.5, -1.5*(GLfloat)h/(GLfloat)w, + 1.5*(GLfloat)h/(GLfloat)w, -10.0, 10.0); + else + glOrtho (-1.5*(GLfloat)w/(GLfloat)h, + 1.5*(GLfloat)w/(GLfloat)h, -1.5, 1.5, -10.0, 10.0); + glMatrixMode(GL_MODELVIEW); + glLoadIdentity(); +} + +void animate(void) +{ + if (solidZ <= MINZ || transparentZ >= MAXZ) + glutIdleFunc(NULL); + else { + solidZ -= ZINC; + transparentZ += ZINC; + glutPostRedisplay(); + } +} + +/* ARGSUSED1 */ +void keyboard(unsigned char key, int x, int y) +{ + switch (key) { + case 'a': + case 'A': + solidZ = MAXZ; + transparentZ = MINZ; + glutIdleFunc(animate); + break; + case 'r': + case 'R': + solidZ = MAXZ; + transparentZ = MINZ; + glutPostRedisplay(); + break; + case 27: + exit(0); + } +} + +int main(int argc, char** argv) +{ + glutInit(&argc, argv); + glutInitDisplayMode (GLUT_SINGLE | GLUT_RGB | GLUT_DEPTH); + glutInitWindowSize(500, 500); + glutCreateWindow(argv[0]); + init(); + glutReshapeFunc(reshape); + glutKeyboardFunc(keyboard); + glutDisplayFunc(display); + glutMainLoop(); + return 0; +} |