1GL_APPLE_object_purgeable 2http://www.opengl.org/registry/specs/APPLE/object_purgeable.txt 3GL_APPLE_object_purgeable 4 GL_BUFFER_OBJECT_APPLE 0x85B3 5 GL_RELEASED_APPLE 0x8A19 6 GL_VOLATILE_APPLE 0x8A1A 7 GL_RETAINED_APPLE 0x8A1B 8 GL_UNDEFINED_APPLE 0x8A1C 9 GL_PURGEABLE_APPLE 0x8A1D 10 void glGetObjectParameterivAPPLE (GLenum objectType, GLuint name, GLenum pname, GLint* params) 11 GLenum glObjectPurgeableAPPLE (GLenum objectType, GLuint name, GLenum option) 12 GLenum glObjectUnpurgeableAPPLE (GLenum objectType, GLuint name, GLenum option) 13