[OpenGL]예제3_회전하는 정사면체, 애니메이션

#include <iostream>
#include <gl/glut.h>
#include <math.h>
 
double cubeLen = 2 * sqrt(2);
 
GLubyte halftone[] = {
    0xAA, 0xAA, 0xAA, 0xAA, 0x55, 0x55, 0x55, 0x55,
    0xAA, 0xAA, 0xAA, 0xAA, 0x55, 0x55, 0x55, 0x55,
    0xAA, 0xAA, 0xAA, 0xAA, 0x55, 0x55, 0x55, 0x55,
    0xAA, 0xAA, 0xAA, 0xAA, 0x55, 0x55, 0x55, 0x55,
    0xAA, 0xAA, 0xAA, 0xAA, 0x55, 0x55, 0x55, 0x55,
    0xAA, 0xAA, 0xAA, 0xAA, 0x55, 0x55, 0x55, 0x55,
    0xAA, 0xAA, 0xAA, 0xAA, 0x55, 0x55, 0x55, 0x55,
    0xAA, 0xAA, 0xAA, 0xAA, 0x55, 0x55, 0x55, 0x55,
    0xAA, 0xAA, 0xAA, 0xAA, 0x55, 0x55, 0x55, 0x55,
    0xAA, 0xAA, 0xAA, 0xAA, 0x55, 0x55, 0x55, 0x55,
    0xAA, 0xAA, 0xAA, 0xAA, 0x55, 0x55, 0x55, 0x55,
    0xAA, 0xAA, 0xAA, 0xAA, 0x55, 0x55, 0x55, 0x55,
    0xAA, 0xAA, 0xAA, 0xAA, 0x55, 0x55, 0x55, 0x55,
    0xAA, 0xAA, 0xAA, 0xAA, 0x55, 0x55, 0x55, 0x55,
    0xAA, 0xAA, 0xAA, 0xAA, 0x55, 0x55, 0x55, 0x55,
    0xAA, 0xAA, 0xAA, 0xAA, 0x55, 0x55, 0x55, 0x55 };
 
 
GLubyte fly[] = {
    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
    0x03, 0x80, 0x01, 0xC0, 0x06, 0xC0, 0x03, 0x60,
    0x04, 0x60, 0x06, 0x20, 0x04, 0x30, 0x0C, 0x20,
    0x04, 0x18, 0x18, 0x20, 0x04, 0x0C, 0x30, 0x20,
    0x04, 0x06, 0x60, 0x20, 0x44, 0x03, 0xC0, 0x22,
    0x44, 0x01, 0x80, 0x22, 0x44, 0x01, 0x80, 0x22,
    0x44, 0x01, 0x80, 0x22, 0x44, 0x01, 0x80, 0x22,
    0x44, 0x01, 0x80, 0x22, 0x44, 0x01, 0x80, 0x22,
    0x66, 0x01, 0x80, 0x66, 0x33, 0x01, 0x80, 0xCC,
    0x19, 0x81, 0x81, 0x98, 0x0C, 0xC1, 0x83, 0x30,
    0x07, 0xe1, 0x87, 0xe0, 0x03, 0x3f, 0xfc, 0xc0,
    0x03, 0x31, 0x8c, 0xc0, 0x03, 0x33, 0xcc, 0xc0,
    0x06, 0x64, 0x26, 0x60, 0x0c, 0xcc, 0x33, 0x30,
    0x18, 0xcc, 0x33, 0x18, 0x10, 0xc4, 0x23, 0x08,
    0x10, 0x63, 0xC6, 0x08, 0x10, 0x30, 0x0c, 0x08,
    0x10, 0x18, 0x18, 0x08, 0x10, 0x00, 0x00, 0x08 };
 
 
int angle = 0;
 
void drawBox(){
    glColor3f(1, 0, 0);
    glPolygonStipple(fly);
    glRotatef(angle, 0, 1, 0);
    glBegin(GL_POLYGON);
    glVertex3f(-cubeLen, cubeLen, -cubeLen);
    glVertex3f(-cubeLen, -cubeLen, cubeLen);
    glVertex3f(cubeLen, -cubeLen, -cubeLen);
    glEnd();
 
 
    glColor3f(0, 1, 0);
    glPolygonStipple(halftone);
    glBegin(GL_POLYGON);
    glVertex3f(-cubeLen, cubeLen, -cubeLen);
    glVertex3f(-cubeLen, -cubeLen, cubeLen);
    glVertex3f(cubeLen, cubeLen, cubeLen);
    glEnd();
 
 
    glColor3f(0, 0, 1);
    glPolygonStipple(fly);
    glBegin(GL_POLYGON);
    glVertex3f(-cubeLen, cubeLen, -cubeLen);
    glVertex3f(cubeLen, cubeLen, cubeLen);
    glVertex3f(cubeLen, -cubeLen, -cubeLen);
    glEnd();
 
 
    glColor3f(1, 1, 0);
    glPolygonStipple(halftone);
    glBegin(GL_POLYGON);
    glVertex3f(cubeLen, cubeLen, cubeLen);
    glVertex3f(-cubeLen, -cubeLen, cubeLen);
    glVertex3f(cubeLen, -cubeLen, -cubeLen);
    glEnd();
    
}
 
void display(){
    glClearColor(0, 0, 0, 1);
    glClear(GL_COLOR_BUFFER_BIT);
 
    glViewport(0, 0, 700, 700);
 
    glMatrixMode(GL_PROJECTION);
    glLoadIdentity();
    glOrtho(-4, 4, -4, 4, 0.1, 50);
    glMatrixMode(GL_MODELVIEW);
    glLoadIdentity();
    glEnable(GL_POLYGON_STIPPLE);
    glPushMatrix();
    glTranslatef(0, 0, 0);
    glRotatef(50, 1, 1, 1);
    glScalef(0.5, 0.5, 0.5);
    angle += 1;
    drawBox();
    glPopMatrix();
    glutSwapBuffers();
    glFlush();
}
 
 
 
 
int main(int argc, char** argv){
    glutInit(&argc, argv);
    glutInitDisplayMode(GLUT_DOUBLE | GLUT_RGB);
    glutInitWindowSize(700, 700);
    glutInitWindowPosition(0, 0);
    glutCreateWindow("tetrahedron");
    glutDisplayFunc(display);
    glutIdleFunc(display); //idle 상태에서도 display를 호출해서 새롭게 그린다. -> 애니메이션 제작 가능.
    glutMainLoop();
}