ANTINDX.C

/* 
* (c) Copyright 1993, Silicon Graphics, Inc.
* 1993-1995 Microsoft Corporation
*
* ALL RIGHTS RESERVED
*
* Please refer to OpenGL/readme.txt for additional information
*
*/

/*
* antiindex.c
* The program draws a wireframe icosahedron with
* antialiased lines, in color index mode.
*/
#include "glos.h"

#include <GL/gl.h>
#include <GL/glu.h>
#include <GL/glaux.h>

void myinit(void);
void CALLBACK myReshape(GLsizei w, GLsizei h);
void CALLBACK display(void);

#define RAMPSIZE 16
#define RAMPSTART 32

/* Initialize antialiasing for color index mode,
* including loading a grey color ramp starting
* at RAMPSTART, which must be a multiple of 16.
*/
void myinit(void)
{
int i;

for (i = 0; i < RAMPSIZE; i++) {
GLfloat shade;
shade = (GLfloat) i/(GLfloat) RAMPSIZE;
auxSetOneColor(RAMPSTART+(GLint)i, shade, shade, shade);
}

glEnable (GL_LINE_SMOOTH);
glHint (GL_LINE_SMOOTH_HINT, GL_DONT_CARE);
glLineWidth (1.5);

glClearIndex ((GLfloat) RAMPSTART);
glShadeModel(GL_FLAT);
glDepthFunc(GL_LESS);
glEnable(GL_DEPTH_TEST);
}

/* display() draws an icosahedron.
*/
void CALLBACK display(void)
{
glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
glIndexi(RAMPSTART);
auxWireIcosahedron(1.0);
glFlush();
}

void CALLBACK myReshape(GLsizei w, GLsizei h)
{
if (!h) return;
glViewport(0, 0, w, h);
glMatrixMode(GL_PROJECTION);
glLoadIdentity();
gluPerspective (45.0, (GLfloat) w/(GLfloat) h, 3.0, 5.0);

glMatrixMode(GL_MODELVIEW);
glLoadIdentity ();
glTranslatef (0.0, 0.0, -4.0); /* move object into view */
}

/* Main Loop
* Open window with initial window size, title bar,
* color index display mode, depth buffer,
* and handle input events.
*/
int main(int argc, char** argv)
{
auxInitDisplayMode (AUX_SINGLE | AUX_INDEX | AUX_DEPTH16);
auxInitPosition (0, 0, 400, 400);
auxInitWindow ("Antialiased Lines Using Color Index");
myinit();
auxReshapeFunc (myReshape);
auxMainLoop(display);
return(0);
}