PLANET.C

/* 
 * (c) Copyright 1993, Silicon Graphics, Inc. 
 *               1993-1995 Microsoft Corporation 
 * 
 * ALL RIGHTS RESERVED 
 * 
 * Please refer to OpenGL/readme.txt for additional information 
 * 
 */ 
 
/* 
 *  planet.c 
 *  This program shows how to composite modeling transformations 
 *  to draw translated and rotated models. 
 *  Interaction:  pressing the left, right, up, and down  
 *  arrow keys alters the rotation of the planet around the sun. 
 */ 
#include "glos.h" 
 
#include <GL/gl.h> 
#include <GL/glu.h> 
#include <GL/glaux.h> 
 
void myinit(void); 
void drawPlane(void); 
void CALLBACK dayAdd (void); 
void CALLBACK daySubtract (void); 
void CALLBACK yearAdd (void); 
void CALLBACK yearSubtract (void); 
void CALLBACK display(void); 
void CALLBACK myReshape(GLsizei w, GLsizei h); 
 
static int year = 0, day = 0; 
 
void CALLBACK dayAdd (void) 
{ 
    day = (day + 10) % 360; 
} 
 
void CALLBACK daySubtract (void) 
{ 
    day = (day - 10) % 360; 
} 
 
void CALLBACK yearAdd (void) 
{ 
    year = (year + 5) % 360; 
} 
 
void CALLBACK yearSubtract (void) 
{ 
    year = (year - 5) % 360; 
} 
 
void CALLBACK display(void) 
{ 
    glClear(GL_COLOR_BUFFER_BIT); 
 
    glColor3f (1.0, 1.0, 1.0); 
    glPushMatrix(); 
/*  draw sun    */ 
    auxWireSphere(1.0); 
/*  draw smaller planet */ 
    glRotatef ((GLfloat) year, 0.0, 1.0, 0.0); 
    glTranslatef (2.0, 0.0, 0.0); 
    glRotatef ((GLfloat) day, 0.0, 1.0, 0.0); 
    auxWireSphere(0.2); 
    glPopMatrix(); 
    glFlush(); 
} 
 
void myinit (void) { 
    glShadeModel (GL_FLAT); 
} 
 
void CALLBACK myReshape(GLsizei w, GLsizei h) 
{ 
    if (!h) return; 
    glViewport(0, 0, w, h); 
    glMatrixMode(GL_PROJECTION); 
    glLoadIdentity(); 
    gluPerspective(60.0, (GLfloat) w/(GLfloat) h, 1.0, 20.0); 
    glMatrixMode(GL_MODELVIEW); 
    glLoadIdentity(); 
    glTranslatef (0.0, 0.0, -5.0); 
} 
 
/*  Main Loop 
 *  Open window with initial window size, title bar,  
 *  RGBA display mode, and handle input events. 
 */ 
int main(int argc, char** argv) 
{ 
    auxInitDisplayMode (AUX_SINGLE | AUX_RGB); 
    auxInitPosition (0, 0, 500, 500); 
    auxInitWindow ("Composite Modeling Transformations"); 
    myinit (); 
    auxKeyFunc (AUX_LEFT, yearSubtract); 
    auxKeyFunc (AUX_RIGHT, yearAdd); 
    auxKeyFunc (AUX_UP, dayAdd); 
    auxKeyFunc (AUX_DOWN, daySubtract); 
    auxReshapeFunc (myReshape); 
    auxMainLoop(display); 
    return(0); 
}