TACCUM.C

/* 
 * (c) Copyright 1993, Silicon Graphics, Inc. 
 *               1993-1995 Microsoft Corporation 
 * 
 * ALL RIGHTS RESERVED 
 * 
 * Please refer to OpenGL/readme.txt for additional information 
 * 
 */ 
 
#include "glos.h" 
 
#include <stdio.h> 
#include <string.h> 
#include <stdlib.h> 
#include <gl\glaux.h> 
 
static void Init(void ); 
static void CALLBACK Reshape(int width,int height); 
static void CALLBACK Key_1(void ); 
static void CALLBACK Key_2(void ); 
static void CALLBACK Draw(void ); 
static GLenum Args(int argc,char **argv ); 
 
GLenum doubleBuffer, directRender; 
GLint thing1, thing2; 
 
 
static void Init(void) 
{ 
 
    glClearColor(0.0, 0.0, 0.0, 0.0); 
    glClearAccum(0.0, 0.0, 0.0, 0.0); 
 
    thing1 = glGenLists(1); 
    glNewList(thing1, GL_COMPILE); 
    glColor3f(1.0, 0.0, 0.0); 
    glRectf(-1.0, -1.0, 1.0, 0.0); 
    glEndList(); 
 
    thing2 = glGenLists(1); 
    glNewList(thing2, GL_COMPILE); 
    glColor3f(0.0, 1.0, 0.0); 
    glRectf(0.0, -1.0, 1.0, 1.0); 
    glEndList(); 
} 
 
static void CALLBACK Reshape(int width, int height) 
{ 
 
    glViewport(0, 0, (GLint)width, (GLint)height); 
 
    glMatrixMode(GL_PROJECTION); 
    glLoadIdentity(); 
    glMatrixMode(GL_MODELVIEW); 
    glLoadIdentity(); 
} 
 
static void CALLBACK Key_1(void) 
{ 
    glPolygonMode(GL_FRONT_AND_BACK, GL_FILL); 
} 
 
static void CALLBACK Key_2(void) 
{ 
    glPolygonMode(GL_FRONT_AND_BACK, GL_LINE); 
} 
 
static void CALLBACK Draw(void) 
{ 
 
    glPushMatrix(); 
 
    glScalef(0.8, 0.8, 1.0); 
 
    glClear(GL_COLOR_BUFFER_BIT); 
    glCallList(thing1); 
    glAccum(GL_LOAD, 0.5); 
 
    glClear(GL_COLOR_BUFFER_BIT); 
    glCallList(thing2); 
    glAccum(GL_ACCUM, 0.5); 
 
    glAccum(GL_RETURN, 1.0); 
 
    glPopMatrix(); 
 
    glFlush(); 
 
    if (doubleBuffer) { 
    auxSwapBuffers(); 
    } 
} 
 
static GLenum Args(int argc, char **argv) 
{ 
    GLint i; 
 
    doubleBuffer = GL_FALSE; 
 
    for (i = 1; i < argc; i++) { 
    if (strcmp(argv[i], "-sb") == 0) { 
        doubleBuffer = GL_FALSE; 
    } else if (strcmp(argv[i], "-db") == 0) { 
        doubleBuffer = GL_TRUE; 
    } else { 
        //printf("%s (Bad option).\n", argv[i]); 
        return GL_FALSE; 
    } 
    } 
    return GL_TRUE; 
} 
 
void main(int argc, char **argv) 
{ 
    GLenum type; 
 
    if (Args(argc, argv) == GL_FALSE) { 
    auxQuit(); 
    } 
 
    auxInitPosition(0, 0, 300, 300); 
 
    type = AUX_RGB | AUX_ACCUM; 
    type |= (doubleBuffer) ? AUX_DOUBLE : AUX_SINGLE; 
 
    auxInitDisplayMode(type); 
 
    if (auxInitWindow("Accum Test") == GL_FALSE) { 
    auxQuit(); 
    } 
 
    Init(); 
 
    auxExposeFunc((AUXEXPOSEPROC)Reshape); 
    auxReshapeFunc((AUXRESHAPEPROC)Reshape); 
    auxKeyFunc(AUX_1, Key_1); 
    auxKeyFunc(AUX_2, Key_2); 
    auxMainLoop(Draw); 
}