ANTIPOLY.C

/* 
 * (c) Copyright 1993, Silicon Graphics, Inc. 
 *               1993-1995 Microsoft Corporation 
 * 
 * ALL RIGHTS RESERVED 
 * 
 * Please refer to OpenGL/readme.txt for additional information 
 * 
 */ 
 
/* 
 *  antipoly.c 
 *  This program draws filled polygons with antialiased 
 *  edges.  The special GL_SRC_ALPHA_SATURATE blending  
 *  function is used. 
 *  Pressing the left mouse button turns the antialiasing 
 *  on and off. 
 */ 
#include "glos.h" 
 
#include <GL/gl.h> 
#include <GL/glu.h> 
#include <GL/glaux.h> 
 
void myinit(void); 
void CALLBACK toggleSmooth (AUX_EVENTREC *event); 
void CALLBACK myReshape(GLsizei w, GLsizei h); 
void CALLBACK display(void); 
 
GLboolean polySmooth; 
 
void myinit(void) 
{ 
    GLfloat mat_ambient[] = { 0.0, 0.0, 0.0, 1.00 }; 
    GLfloat mat_specular[] = { 1.0, 1.0, 1.0, 1.00 }; 
    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); 
    glEnable (GL_BLEND); 
    glCullFace (GL_BACK); 
    glEnable (GL_CULL_FACE); 
    glEnable (GL_POLYGON_SMOOTH); 
    polySmooth = GL_TRUE; 
 
    glClearColor (0.0, 0.0, 0.0, 0.0); 
} 
 
void CALLBACK toggleSmooth (AUX_EVENTREC *event) 
{ 
    if (polySmooth) { 
    polySmooth = GL_FALSE; 
    glDisable (GL_BLEND); 
    glDisable (GL_POLYGON_SMOOTH); 
    glEnable (GL_DEPTH_TEST); 
    } 
    else { 
    polySmooth = GL_TRUE; 
    glEnable (GL_BLEND); 
    glEnable (GL_POLYGON_SMOOTH); 
    glDisable (GL_DEPTH_TEST); 
    } 
} 
 
/*  Note:  polygons must be drawn from front to back 
 *  for proper blending. 
 */ 
void CALLBACK display(void) 
{ 
    GLfloat position[] = { 0.0, 0.0, 1.0, 0.0 }; 
    GLfloat mat_cube1[] = { 0.75, 0.75, 0.0, 1.0 }; 
    GLfloat mat_cube2[] = { 0.0, 0.75, 0.75, 1.0 }; 
 
    if (polySmooth) 
    glClear (GL_COLOR_BUFFER_BIT); 
    else  
    glClear (GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT); 
 
    glPushMatrix (); 
    glTranslatef (0.0, 0.0, -8.0);     
    glLightfv (GL_LIGHT0, GL_POSITION, position); 
 
    glBlendFunc (GL_SRC_ALPHA_SATURATE, GL_ONE); 
 
    glPushMatrix (); 
    glRotatef (30.0, 1.0, 0.0, 0.0); 
    glRotatef (60.0, 0.0, 1.0, 0.0); 
    glMaterialfv(GL_FRONT, GL_DIFFUSE, mat_cube1); 
    auxSolidCube (1.0); 
    glPopMatrix (); 
 
    glTranslatef (0.0, 0.0, -2.0);     
    glMaterialfv(GL_FRONT, GL_DIFFUSE, mat_cube2); 
    glRotatef (30.0, 0.0, 1.0, 0.0); 
    glRotatef (60.0, 1.0, 0.0, 0.0); 
    auxSolidCube (1.0); 
 
    glPopMatrix (); 
 
    glFlush (); 
} 
 
void CALLBACK myReshape(GLsizei w, GLsizei h) 
{ 
    h = (h == 0) ? 1 : h; 
    glViewport(0, 0, w, h); 
    glMatrixMode(GL_PROJECTION); 
    glLoadIdentity(); 
    gluPerspective(30.0, (GLfloat) w/(GLfloat) h, 1.0, 20.0); 
    glMatrixMode(GL_MODELVIEW); 
} 
 
/*  Main Loop 
 */ 
int main(int argc, char** argv) 
{ 
    auxInitDisplayMode (AUX_SINGLE | AUX_RGB | AUX_ALPHA | AUX_DEPTH16); 
    auxInitPosition (0, 0, 200, 200); 
    auxInitWindow ("Antialiased Edges"); 
    auxMouseFunc (AUX_LEFTBUTTON, AUX_MOUSEDOWN, toggleSmooth); 
    myinit(); 
    auxReshapeFunc (myReshape); 
    auxMainLoop(display); 
    return(0); 
}