MAPLIGHT.C

/* 
 * (c) Copyright 1993, Silicon Graphics, Inc. 
 *               1993-1995 Microsoft Corporation 
 * 
 * ALL RIGHTS RESERVED 
 * 
 * Please refer to OpenGL/readme.txt for additional information 
 * 
 */ 
 
/* 
 *  maplight.c 
 *  This program demonstrates the use of the GL lighting model. 
 *  A sphere is drawn using a magenta diffuse reflective and 
 *  white specular material property. 
 *  A single light source illuminates the object.  This program 
 *  illustrates lighting in color map mode. 
 */ 
#include "glos.h" 
 
#include <GL/gl.h> 
#include <GL/glu.h> 
#include <GL/glaux.h> 
 
void myinit(void); 
void CALLBACK display(void); 
void CALLBACK myReshape(GLsizei w, GLsizei h); 
 
/*  Initialize material property, light source, and lighting model. 
 */ 
void myinit(void) 
{ 
    GLint i; 
 
    GLfloat light_position[] = { 1.0, 1.0, 1.0, 0.0 }; 
    GLfloat mat_colormap[] = { 16.0, 48.0, 79.0 }; 
    GLfloat mat_shininess[] = { 10.0 }; 
     
    glMaterialfv(GL_FRONT, GL_COLOR_INDEXES, mat_colormap); 
    glMaterialfv(GL_FRONT, GL_SHININESS, mat_shininess); 
    glLightfv(GL_LIGHT0, GL_POSITION, light_position); 
 
    glEnable(GL_LIGHTING); 
    glEnable(GL_LIGHT0); 
 
    glDepthFunc(GL_LESS); 
    glEnable(GL_DEPTH_TEST); 
 
    for (i = 0; i < 32; i++) { 
    auxSetOneColor (16 + i, 1.0 * (i/32.0), 0.0, 1.0 * (i/32.0)); 
    auxSetOneColor (48 + i, 1.0, 1.0 * (i/32.0), 1.0); 
    } 
    glClearIndex(0); 
} 
 
void CALLBACK display(void) 
{ 
    glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT); 
    auxSolidSphere(1.0); 
    glFlush(); 
} 
 
void CALLBACK myReshape(GLsizei w, GLsizei h) 
{ 
    if (!h) return; 
    glViewport(0, 0, w, 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(); 
} 
 
/*  Main Loop 
 *  Open window with initial window size, title bar, color  
 *  index display mode, and handle input events. 
 */ 
int main(int argc, char** argv) 
{ 
    auxInitDisplayMode (AUX_SINGLE | AUX_INDEX | AUX_DEPTH16); 
    auxInitPosition (0, 0, 500, 500); 
    auxInitWindow ("Lighting in Color Map Mode"); 
    myinit(); 
    auxReshapeFunc (myReshape); 
    auxMainLoop(display); 
    return(0); 
}