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/*
* (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* Unpublished-- rights reserved under the copyright laws of the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.
*/
/*
* alpha3D.c
* This program demonstrates how to intermix opaque and
* alpha blended polygons in the same scene, by using glDepthMask.
* Pressing the left mouse button toggles the eye position.
*/
#include <GL/gl.h>
#include <GL/glu.h>
#include <stdlib.h>
#include "glaux.h"
void myinit(void)
{
GLfloat mat_ambient[] = { 0.0, 0.0, 0.0, 0.15 };
GLfloat mat_specular[] = { 1.0, 1.0, 1.0, 0.15 };
GLfloat mat_shininess[] = { 15.0 };
glMaterialfv(GL_FRONT, GL_AMBIENT, mat_ambient);
glMaterialfv(GL_FRONT, GL_SPECULAR, mat_specular);
glMaterialfv(GL_FRONT, GL_SHININESS, mat_shininess);
glEnable (GL_LIGHTING);
glEnable (GL_LIGHT0);
glDepthFunc(GL_LESS);
glEnable(GL_DEPTH_TEST);
}
GLboolean eyePosition = GL_FALSE;
void toggleEye (AUX_EVENTREC *event)
{
if (eyePosition)
eyePosition = GL_FALSE;
else
eyePosition = GL_TRUE;
}
void display(void)
{
GLfloat position[] = { 0.0, 0.0, 1.0, 1.0 };
GLfloat mat_torus[] = { 0.75, 0.75, 0.0, 1.0 };
GLfloat mat_cylinder[] = { 0.0, 0.75, 0.75, 0.15 };
glClear (GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
glLightfv (GL_LIGHT0, GL_POSITION, position);
glPushMatrix ();
if (eyePosition)
gluLookAt (0.0, 0.0, 9.0, 0.0, 0.0, 0.0, 0.0, 1.0, 0.0);
else
gluLookAt (0.0, 0.0, -9.0, 0.0, 0.0, 0.0, 0.0, 1.0, 0.0);
glPushMatrix ();
glTranslatef (0.0, 0.0, 1.0);
glMaterialfv(GL_FRONT, GL_DIFFUSE, mat_torus);
auxSolidTorus (0.275, 0.85);
glPopMatrix ();
glEnable (GL_BLEND);
glDepthMask (GL_FALSE);
glBlendFunc (GL_SRC_ALPHA, GL_ONE);
glMaterialfv(GL_FRONT, GL_DIFFUSE, mat_cylinder);
glTranslatef (0.0, 0.0, -1.0);
auxSolidCylinder (1.0, 2.0);
glDepthMask (GL_TRUE);
glDisable (GL_BLEND);
glPopMatrix ();
glFlush ();
}
void myReshape(int w, int h)
{
glViewport(0, 0, w, h);
glMatrixMode(GL_PROJECTION);
glLoadIdentity();
gluPerspective(30.0, (GLfloat) w/(GLfloat) h, 1.0, 20.0);
glMatrixMode(GL_MODELVIEW);
glLoadIdentity();
}
/* Main Loop
* Open window with initial window size, title bar,
* RGBA display mode, and handle input events.
*/
int gl_width=500;
int gl_height=500;
void render_image(void)
{
myinit();
myReshape(gl_width,gl_height);
display();
}
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