windows-nt/Source/XPSP1/NT/multimedia/opengl/test/auxprogs/index/fogindex.c
2020-09-26 16:20:57 +08:00

133 lines
4.2 KiB
C

/*
* (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* Unpublished-- rights reserved under the copyright laws of the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.
*/
/*
* fogindex.c
* This program demonstrates fog in color index mode.
* Three cones are drawn at different z values in a linear
* fog. 32 contiguous colors (from 16 to 47) are loaded
* with a color ramp.
*/
#include <windows.h>
#include <GL/gl.h>
#include <GL/glu.h>
#include "glaux.h"
/* Initialize color map and fog. Set screen clear color
* to end of color ramp.
*/
#define NUMCOLORS 32
#define RAMPSTART 16
void myinit(void)
{
int i;
glEnable(GL_DEPTH_TEST);
glDepthFunc(GL_LESS);
for (i = 0; i < NUMCOLORS; i++) {
GLfloat shade;
shade = (GLfloat) (NUMCOLORS-i)/(GLfloat) NUMCOLORS;
auxSetOneColor (16 + i, shade, shade, shade);
}
glEnable(GL_FOG);
glFogi (GL_FOG_MODE, GL_LINEAR);
glFogi (GL_FOG_INDEX, NUMCOLORS);
glFogf (GL_FOG_START, 0.0);
glFogf (GL_FOG_END, 4.0);
glHint (GL_FOG_HINT, GL_NICEST);
glClearIndex((GLfloat) (NUMCOLORS+RAMPSTART-1));
}
/* display() renders 3 cones at different z positions.
*/
void display(void)
{
glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
glPushMatrix ();
glTranslatef (-1.0, -1.0, -1.0);
glRotatef (-90.0, 1.0, 0.0, 0.0);
glIndexi (RAMPSTART);
auxSolidCone(1.0, 2.0);
glPopMatrix ();
glPushMatrix ();
glTranslatef (0.0, -1.0, -2.25);
glRotatef (-90.0, 1.0, 0.0, 0.0);
glIndexi (RAMPSTART);
auxSolidCone(1.0, 2.0);
glPopMatrix ();
glPushMatrix ();
glTranslatef (1.0, -1.0, -3.5);
glRotatef (-90.0, 1.0, 0.0, 0.0);
glIndexi (RAMPSTART);
auxSolidCone(1.0, 2.0);
glPopMatrix ();
glFlush();
}
void myReshape(GLsizei w, GLsizei h)
{
glViewport(0, 0, w, h);
glMatrixMode(GL_PROJECTION);
glLoadIdentity();
if (w <= h)
glOrtho (-2.0, 2.0, -2.0*(GLfloat)h/(GLfloat)w,
2.0*(GLfloat)h/(GLfloat)w, 0.0, 10.0);
else
glOrtho (-2.0*(GLfloat)w/(GLfloat)h,
2.0*(GLfloat)w/(GLfloat)h, -2.0, 2.0, 0.0, 10.0);
glMatrixMode(GL_MODELVIEW);
glLoadIdentity ();
}
/* Main Loop
* Open window with initial window size, title bar,
* RGBA display mode, depth buffer, and handle input events.
*/
int main(int argc, char** argv)
{
auxInitDisplayMode (AUX_SINGLE | AUX_INDEX | AUX_DEPTH16);
auxInitPosition (0, 0, 200, 200);
auxInitWindow (argv[0]);
myinit();
auxReshapeFunc (myReshape);
auxMainLoop(display);
}