알파블렌딩, 알파텍스쳐, fade-in/out, fog, glDepthMask(GL_FALSE), glEnable(GL_CULL_FACE), 블렌딩시 draw order, filtering, lightmap 기법
http://dis.dankook.ac.kr/lectures/cg07/entry/blending-예제
OPENGL alpha blending, fog 예제
http://dis.dankook.ac.kr/lectures/cg07/entry/OpenGL-alpha-fog-예제