구차니의 잡동사니 모음

glViewport를 사용하지 않고 창의 크기를 변화시켰을 경우

#include "windows.h"
#include "GL/gl.h"
#include "GL/glu.h"
#include "GL/glut.h"

static int year = 0, day = 0;

void display(void)
{
	glClear(GL_COLOR_BUFFER_BIT);
	glColor3f(1.0, 1.0, 1.0);

	glPushMatrix();
		glutWireSphere(1.0, 20, 16);   /* draw sun */

		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);
		glutWireSphere(0.2, 10, 8);    /* draw smaller planet */
	glPopMatrix();

	glutSwapBuffers();
}

void reshape(int w, int h)
{
	glViewport(0, 0, (GLsizei) w, (GLsizei) h); 
	glMatrixMode(GL_PROJECTION);
		glLoadIdentity();
		gluPerspective(60.0, (GLfloat) w/(GLfloat) h, 1.0, 20.0);
	
	glMatrixMode(GL_MODELVIEW); //GL_PROJECTION
		glLoadIdentity();
		gluLookAt(0.0, 0.0, 5.0, 0.0, 0.0, 0.0, 0.0, 1.0, 0.0);
}

void keyboard(unsigned char key, int x, int y)
{
	switch (key)
	{
	  case 'd':
		  day = (day + 10) % 360;
		  glutPostRedisplay();
		  break;
	  case 'D':
		  day = (day - 10) % 360;
		  glutPostRedisplay();
		  break;
	  case 'y':
		  year = (year + 5) % 360;
		  glutPostRedisplay();
		  break;
	  case 'Y':
		  year = (year - 5) % 360;
		  glutPostRedisplay();
		  break;
	  default:
		  break;
	}
}

int main(int argc, char** argv)
{
	glutInit(&argc, argv);
	glutInitDisplayMode(GLUT_DOUBLE | GLUT_RGB);
	glutInitWindowSize(500, 500); 
	glutInitWindowPosition(100, 100);
	glutCreateWindow(argv[0]);

	glClearColor(0.0, 0.0, 0.0, 0.0);
	glShadeModel(GL_FLAT); //GL_SMOOTH

	glutDisplayFunc(display); 
	glutReshapeFunc(reshape);
	glutKeyboardFunc(keyboard);
	glutMainLoop();
	return 0;
}

#include "windows.h"
#include "GL/gl.h"
#include "GL/glut.h"

void display(void)
{
/*  clear all pixels  */
    glClear (GL_COLOR_BUFFER_BIT);
/*  draw white polygon (rectangle) with corners at
 *  (0.25, 0.25, 0.0) and (0.75, 0.75, 0.0)  
 */
    glColor3f (1.0, 1.0, 1.0);
    glBegin(GL_POLYGON);
        glVertex3f (0.25, 0.25, 0.0);
        glVertex3f (0.75, 0.25, 0.0);
        glVertex3f (0.75, 0.75, 0.0);
        glVertex3f (0.25, 0.75, 0.0);
    glEnd();
/*  don’t wait!  
 *  start processing buffered OpenGL routines 
 */
    glFlush ();
}
void init (void) 
{
/*  select clearing (background) color       */
    glClearColor (0.0, 0.0, 0.0, 0.0);
/*  initialize viewing values  */
    glMatrixMode(GL_PROJECTION);
    glLoadIdentity();
    glOrtho(0.0, 1.0, 0.0, 1.0, -1.0, 1.0);
}
/* 
 *  Declare initial window size, position, and display mode
 *  (single buffer and RGBA).  Open window with "hello"
 *  in its title bar.  Call initialization routines.
 *  Register callback function to display graphics.
 *  Enter main loop and process events.
 */
int main(int argc, char** argv)
{
    glutInit(&argc, argv);
    glutInitDisplayMode (GLUT_SINGLE | GLUT_RGB);
    glutInitWindowSize (250, 250); 
    glutInitWindowPosition (100, 100);
    glutCreateWindow ("hello");
    init ();
    glutDisplayFunc(display);
    glutMainLoop();
    return 0;   /* ISO C requires main to return int. */
}