#2. OpenGL 두번째 예제. 사각형 그려보기

소스
 

1 #include <GL/glut.h>
 2
 3 void drawRectangle(GLfloat x, GLfloat y, GLfloat r, GLfloat g, GLfloat b)
 4 {
 5     static GLfloat width = 1.0;
 6     static GLfloat height = 1.0;
 7
 8     glBegin(GL_POLYGON);
 9     {
10         glColor3f(r,g,b);
11         glVertex2f(x,y);
12         glColor3f(r,b,g);
13         glVertex2f(x+width,y);
14         glColor3f(g,r,b);
15         glVertex2f(x+width,y+height);
16         glColor3f(b,g,r);
17         glVertex2f(x,y+height);
18     }
19     glEnd();
20 }
21
22 void DoDisplay()
23 {
24     glClear(GL_COLOR_BUFFER_BIT);
25     drawRectangle(-0.5,-0.5, 0.8,0.2,0.1);
26     glFlush();
27 }
28
29 int main(int argc, char *argv[])
30 {
31     glutInit( &argc, argv );
32     glutCreateWindow("OpenGL");
33     glutDisplayFunc(DoDisplay);
34     glutMainLoop();
35 }

컴파일

$ gcc -o sample4 sample4.c -lglut

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