glColor*

glColor의 경우 클램프되어 있는 변수는 아니나

내부적으로 clamp 되어 사용이 된다.

void glColor3f( GLfloat red, GLfloat green, GLfloat blue )

Neither floating-point nor signed integer values are clamped to the range [0,1] before the current color is updated. However, color components are clamped to this range before they are interpolated or written into a color buffer.

[링크 : http://linux.die.net/man/3/glcolor3f]

void glClearColor( GLclampf red, GLclampf green, GLclampf blue, GLclampf alpha )

[링크 : http://linux.die.net/man/3/glclearcolor]