| Name |
| |
| EXT_abgr |
| |
| Name Strings |
| |
| GL_EXT_abgr |
| |
| Version |
| |
| $Date: 1995/03/31 04:40:18 $ $Revision: 1.10 $ |
| |
| Number |
| |
| 1 |
| |
| Dependencies |
| |
| None |
| |
| Overview |
| |
| EXT_abgr extends the list of host-memory color formats. Specifically, |
| it provides a reverse-order alternative to image format RGBA. The ABGR |
| component order matches the cpack Iris GL format on big-endian machines. |
| |
| New Procedures and Functions |
| |
| None |
| |
| New Tokens |
| |
| Accepted by the <format> parameter of DrawPixels, GetTexImage, |
| ReadPixels, TexImage1D, and TexImage2D: |
| |
| ABGR_EXT 0x8000 |
| |
| Additions to Chapter 2 of the GL Specification (OpenGL Operation) |
| |
| None |
| |
| Additions to Chapter 3 of the GL Specification (Rasterization) |
| |
| One entry is added to table 3.5 (DrawPixels and ReadPixels formats). |
| The new table is: |
| |
| Target |
| Name Type Elements Buffer |
| ---- ---- -------- ------ |
| COLOR_INDEX Index Color Index Color |
| STENCIL_INDEX Index Stencil value Stencil |
| DEPTH_COMPONENT Component Depth value Depth |
| RED Component R Color |
| GREEN Component G Color |
| BLUE Component B Color |
| ALPHA Component A Color |
| RGB Component R, G, B Color |
| RGBA Component R, G, B, A Color |
| LUMINANCE Component Luminance value Color |
| LUMINANCE_ALPHA Component Luminance value, A Color |
| ABGR_EXT Component A, B, G, R Color |
| |
| Table 3.5: DrawPixels and ReadPixels formats. The third column |
| gives a description of and the number and order of elements in a |
| group. |
| |
| Additions to Chapter 4 of the GL Specification (Per-Fragment Operations |
| and the Framebuffer) |
| |
| The new format is added to the discussion of Obtaining Pixels from the |
| Framebuffer. It should read " If the <format> is one of RED, GREEN, |
| BLUE, ALPHA, RGB, RGBA, ABGR_EXT, LUMINANCE, or LUMINANCE_ALPHA, and |
| the GL is in color index mode, then the color index is obtained." |
| |
| The new format is added to the discussion of Index Lookup. It should |
| read "If <format> is one of RED, GREEN, BLUE, ALPHA, RGB, RGBA, |
| ABGR_EXT, LUMINANCE, or LUMINANCE_ALPHA, then the index is used to |
| reference 4 tables of color components: PIXEL_MAP_I_TO_R, |
| PIXEL_MAP_I_TO_G, PIXEL_MAP_I_TO_B, and PIXEL_MAP_I_TO_A." |
| |
| Additions to Chapter 5 of the GL Specification (Special Functions) |
| |
| None |
| |
| Additions to Chapter 6 of the GL Specification (State and State Requests) |
| |
| None |
| |
| Additions to the GLX Specification |
| |
| None |
| |
| GLX Protocol |
| |
| One entry is added to tables 1 and 5 in the GLX Protocol Specification: |
| |
| format encoding |
| ------ -------- |
| GL_ABGR_EXT 0x8000 |
| |
| Table A.2 is also extended: |
| |
| format nelements |
| ------ -------- |
| GL_ABGR_EXT 4 |
| |
| |
| Errors |
| |
| None |
| |
| New State |
| |
| None |
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| New Implementation Dependent State |
| |
| None |