실습 2주차

#include <GL/glut.h>

GLfloat vertices[8][3] = {{ -1.0, -1.0, 1.0}, {-1.0, 1.0, 1.0},
{1.0, 1.0, 1.0}, {1.0, -1.0, 1.0}, {-1.0, -1.0, -1.0},
{-1.0, 1.0, -1.0}, {1.0, 1.0, -1.0}, {1.0, -1.0, -1.0}};

GLfloat colors[8][3] = {{0.0, 0.0, 0.0}, {1.0, 0.0, 0.0},
{1.0, 1.0, 0.0}, {0.0, 1.0, 0.0}, {0.0, 0.0, 1.0},
{1.0, 0.0, 1.0}, {1.0, 1.0, 1.0}, {0.0, 1.0, 1.0}};

void init(void)
{
 glClearColor(0.0f, 0.0f, 0.0f, 0.0f);
}

void quad(int a, int b, int c, int d)
{
 glBegin(GL_QUADS);
 glColor3fv(colors[a]);
 glVertex3fv(vertices[a]);
 glColor3fv(colors[b]);
 glVertex3fv(vertices[b]);
 glColor3fv(colors[c]);
 glVertex3fv(vertices[c]);
 glColor3fv(colors[d]);
 glVertex3fv(vertices[d]);
 glEnd();
}

/*
void cube()
{
 quad(0, 3, 2, 1);//앞면
 quad(2, 3, 7, 6);//오른쪽면
 quad(0, 4, 7, 3);//아랫면
 quad(0, 4, 7, 3);//윗면
 quad(4, 5, 6, 7);//뒷면
 quad(0, 1, 5, 4);//왼쪽면
}
*/

void cube()
{

 /*
 glBegin(GL_LINE_LOOP);
 //glColor3f(0.0f, 1.0f, 1.0f);
 glVertex3f(0.0f, 0.0f, 1.0f);
 glVertex3f(1.0f, 0.0f, 1.0f);
 glVertex3f(1.0f, 1.0f, 1.0f);
 glVertex3f(0.0f, 1.0f, 1.0f);
 glEnd();

 glBegin(GL_LINE_LOOP);
 //glColor3f(1.0f, 1.0f, 0.0f);
 glVertex3f(0.0f, 0.0f, 0.0f);
 glVertex3f(1.0f, 0.0f, 0.0f);
 glVertex3f(1.0f, 1.0f, 0.0f);
 glVertex3f(0.0f, 1.0f, 0.0f);
 glEnd();

 glBegin(GL_LINES);
 //glColor3f(1.0f, 1.0f, 0.0f);
 glVertex3f(0.0f, 0.0f, 0.0f);
 glVertex3f(0.0f, 0.0f, 1.0f);
 glVertex3f(0.0f, 1.0f, 0.0f);
 glVertex3f(0.0f, 1.0f, 1.0f);

 //glColor3f(1.0f, 0.0f, 1.0f);
 glVertex3f(1.0f, 0.0f, 0.0f);
 glVertex3f(1.0f, 0.0f, 1.0f);
 glVertex3f(1.0f, 1.0f, 0.0f);
 glVertex3f(1.0f, 1.0f, 1.0f);
 glEnd();

 */

 //color cube 만들기
 glBegin(GL_QUADS);
 glColor3f(1.0f, 0.0f, 0.0f);
 glVertex3f(-1.0f, -1.0f, 1.0f);
 glVertex3f(1.0f, -1.0f, 1.0f);
 glVertex3f(1.0f, 1.0f, 1.0f);
 glVertex3f(-1.0f, 1.0f, 1.0f);

 glColor3f(1.0f, 1.0f, 0.5f);
 glVertex3f(1.0f, 1.0f, 1.0f);
 glVertex3f(1.0f, -1.0f, 1.0f);
 glVertex3f(1.0f, -1.0f, -1.0f);
 glVertex3f(1.0f, 1.0f, -1.0f);

 glColor3f(0.0f, 0.0f, 1.0f);
 glVertex3f(-1.0f, 1.0f, -1.0f);
 glVertex3f(-1.0f, -1.0f, -1.0f);
 glVertex3f(1.0f, -1.0f, -1.0f);
 glVertex3f(1.0f, 1.0f, -1.0f);

 glColor3f(1.0f, 1.0f, 0.0f);
 glVertex3f(-1.0f, 1.0f, -1.0f);
 glVertex3f(-1.0f, -1.0f, -1.0f);
 glVertex3f(-1.0f, -1.0f, 1.0f);
 glVertex3f(-1.0f, 1.0f, 1.0f);

 glColor3f(0.0f, 1.0f, 1.0f);
 glVertex3f(-1.0f, -1.0f, -1.0f);
 glVertex3f(-1.0f, -1.0f, 1.0f);
 glVertex3f(1.0f, -1.0f, 1.0f);
 glVertex3f(1.0f, -1.0f, -1.0f);

 glColor3f(1.0f, 1.0f, 1.0f);
 glVertex3f(-1.0f, 1.0f, -1.0f);
 glColor3f(1.0f, 0.0f, 1.0f);
 glVertex3f(-1.0f, 1.0f, 1.0f);
 glColor3f(0.0f, 1.0f, 0.0f);
 glVertex3f(1.0f, 1.0f, 1.0f);
 glColor3f(1.0f, 1.0f, 0.0f);
 glVertex3f(1.0f, 1.0f, -1.0f);
 glEnd();

}

void coordinateaxis()
{
 glColor3f(1.0, 0.0, 0.0);
 //각 좌표축 그려줌
 glBegin(GL_LINES);
 glVertex3f(0.0, 0.0, 0.0);
 glVertex3f(2.5, 0.0, 0.0);
 glVertex3f(2.5, 0.0, 0.0);
  glVertex3f(2.45, 0.05, 0.0); //화살표
 glVertex3f(2.5, 0.0, 0.0);
 glVertex3f(2.45, -0.05, 0.0);

 glVertex3f(0.0, 0.0, 0.0);
 glVertex3f(0.0, 2.5, 0.0);
 glVertex3f(0.0, 2.5, 0.0);
 glVertex3f(0.05, 2.45, 0.0);
 glVertex3f(0.0, 2.5, 0.0);
 glVertex3f(-0.05, 2.45, 0.0);

 glVertex3f(0.0, 0.0, 0.0);
 glVertex3f(0.0, 0.0, 2.5);
 glVertex3f(0.0, 0.0, 2.5);
  glVertex3f(0.0, 0.05, 2.45); //화살표'
 glVertex3f(0.0, 0.0, 2.5);
 glVertex3f(0.0, -0.05, 2.45);
 glEnd();

 glColor3f(1.0, 0.0, 0.0);
 glRasterPos3f(2.6, 0.0, 0.0);

 //X축 표시
 glutBitmapCharacter(GLUT_BITMAP_9_BY_15, 'X');
 glRasterPos3f(0.0, 2.6, 0.0);

 //Y축 표시
 glutBitmapCharacter(GLUT_BITMAP_9_BY_15, 'Y');
 glRasterPos3f(0.0, 0.0, 2.6);

 //Z축 표시
 glutBitmapCharacter(GLUT_BITMAP_9_BY_15, 'Z');
}

void reshape(GLsizei w, GLsizei h)
{
 GLfloat fovy = 60.0;
 GLfloat aspect;
 if(h == 0) h = 1; //0으로 나누지 않도록 함
 aspect = (GLfloat)w / (GLfloat)h;
 //클리핑 영역 설정
 glViewport(0, 0, w, h);
 //뷰포트를 차의 크기에 맞게 설정
 glMatrixMode(GL_PROJECTION);
 glLoadIdentity();//좌표계 초기화
 gluPerspective(fovy, aspect, 1.0, 100.0);
 glMatrixMode(GL_MODELVIEW);
 glLoadIdentity();
}

void display(void)
{
 glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
 glLoadIdentity();
 //glLookAt(-5.0f, 5.0f, 5.0f, 0.0f, 0.0f, 0.0f, 0.0f, 1.0f, 0.0f);

 glTranslatef(0.0f, 0.0f, -10.0f);
 glRotatef(-30.0f, 0.0f, 1.0f, 0.0f);
 glRotatef(30.0f, 1.0f, 0.0f, 0.0f);
 cube();
 coordinateaxis();
 glFlush();
}

void main(int argc, char** argv)
{
 glutInit (&argc, argv);
 glutInitDisplayMode(GLUT_RGB | GLUT_DEPTH);
 glutInitWindowSize(500, 500);
 glutInitWindowPosition(0,0);
 glutCreateWindow("Cube 그리기");

 glutReshapeFunc(reshape);
 glutDisplayFunc(display);
 init();
 glEnable(GL_DEPTH_TEST);
 glutMainLoop();
}