1GL_ARB_texture_rg
2http://www.opengl.org/registry/specs/ARB/texture_rg.txt
3GL_ARB_texture_rg
4	GL_COMPRESSED_RED 0x8225
5	GL_COMPRESSED_RG 0x8226
6	GL_RG 0x8227
7	GL_RG_INTEGER 0x8228
8	GL_R8 0x8229
9	GL_R16 0x822A
10	GL_RG8 0x822B
11	GL_RG16 0x822C
12	GL_R16F 0x822D
13	GL_R32F 0x822E
14	GL_RG16F 0x822F
15	GL_RG32F 0x8230
16	GL_R8I 0x8231
17	GL_R8UI 0x8232
18	GL_R16I 0x8233
19	GL_R16UI 0x8234
20	GL_R32I 0x8235
21	GL_R32UI 0x8236
22	GL_RG8I 0x8237
23	GL_RG8UI 0x8238
24	GL_RG16I 0x8239
25	GL_RG16UI 0x823A
26	GL_RG32I 0x823B
27	GL_RG32UI 0x823C
28