diff options
Diffstat (limited to 'mesalib/docs/MESA_pack_invert.spec')
-rw-r--r-- | mesalib/docs/MESA_pack_invert.spec | 276 |
1 files changed, 138 insertions, 138 deletions
diff --git a/mesalib/docs/MESA_pack_invert.spec b/mesalib/docs/MESA_pack_invert.spec index 0eeb58c13..33fb3c7bf 100644 --- a/mesalib/docs/MESA_pack_invert.spec +++ b/mesalib/docs/MESA_pack_invert.spec @@ -1,138 +1,138 @@ -Name
-
- MESA_pack_invert
-
-Name Strings
-
- GL_MESA_pack_invert
-
-Contact
-
- Brian Paul, Tungsten Graphics, Inc. (brian.paul 'at' tungstengraphics.com)
- Keith Whitwell, Tungsten Graphics, Inc. (keith 'at' tungstengraphics.com)
-
-Status
-
- Shipping (Mesa 4.0.4 and later)
-
-Version
-
- 1.0
-
-Number
-
- TBD
-
-Dependencies
-
- OpenGL 1.0 or later is required
- This extensions is written against the OpenGL 1.4 Specification.
-
-Overview
-
- This extension adds a new pixel storage parameter to indicate that
- images are to be packed in top-to-bottom order instead of OpenGL's
- conventional bottom-to-top order. Only pixel packing can be
- inverted (i.e. for glReadPixels, glGetTexImage, glGetConvolutionFilter,
- etc).
-
- Almost all known image file formats store images in top-to-bottom
- order. As it is, OpenGL reads images from the frame buffer in
- bottom-to-top order. Thus, images usually have to be inverted before
- writing them to a file with image I/O libraries. This extension
- allows images to be read such that inverting isn't needed.
-
-IP Status
-
- None
-
-Issues
-
- 1. Should we also define UNPACK_INVERT_MESA for glDrawPixels, etc?
-
- Resolved: No, we're only concerned with pixel packing. There are other
- solutions for inverting images when using glDrawPixels (negative Y pixel
- zoom) or glTexImage (invert the vertex T coordinates). It would be easy
- enough to define a complementary extension for pixel packing in the
- future if needed.
-
-New Procedures and Functions
-
- None
-
-New Tokens
-
- Accepted by the <pname> parameter of PixelStorei and PixelStoref
- and the <pname> parameter of GetIntegerv, GetFloatv, GetDoublev
- and GetBooleanv:
-
- PACK_INVERT_MESA 0x8758
-
-Additions to Chapter 2 of the OpenGL 1.4 Specification (OpenGL Operation)
-
- None
-
-Additions to Chapter 3 of the OpenGL 1.4 Specification (Rasterization)
-
- None
-
-Additions to Chapter 4 of the OpenGL 1.4 Specification (Per-Fragment
-Operations and the Frame Buffer)
-
- Add the following entry to table 4.4 (PixelStore parameters) on page 182:
-
- Parameter Name Type Initial Value Valid Range
- ---------------------------------------------------------
- PACK_INVERT_MESA boolean FALSE TRUE/FALSE
-
- In the section labeled "Placement in Client Memory" on page 184
- insert the following text into the paragraph before the sentence
- that starts with "If the format is RED, GREEN, BLUE...":
-
- "The parameter PACK_INVERT_MESA controls whether the image is packed
- in bottom-to-top order (the default) or top-to-bottom order. Equation
- 3.8 is modified as follows:
-
- ... the first element of the Nth row is indicated by
-
- p + Nk, if PACK_INVERT_MESA is false
- p + k * (H - 1) - Nk, if PACK_INVERT_MESA is true, where H is the
- image height
- "
-
-Additions to Chapter 5 of the OpenGL 1.4 Specification (Special Functions)
-
- None
-
-Additions to Chapter 6 of the OpenGL 1.4 Specification (State and
-State Requests)
-
- None
-
-Additions to Appendix A of the OpenGL 1.4 Specification (Invariance)
-
- None
-
-Additions to the AGL/GLX/WGL Specifications
-
- None
-
-GLX Protocol
-
- None
-
-Errors
-
- None
-
-New State
-
- Add the following entry to table 6.20 (Pixels) on page 235:
-
- Get Value Type Get Cmd Initial Value Description Sec Attribute
- --------------------------------------------------------------------------------------------------
- PACK_INVERT_MESA boolean GetBoolean FALSE Value of PACK_INVERT_MESA 4.3.2 pixel-store
-
-Revision History
-
- 21 September 2002 - Initial draft
+Name + + MESA_pack_invert + +Name Strings + + GL_MESA_pack_invert + +Contact + + Brian Paul, Tungsten Graphics, Inc. (brian.paul 'at' tungstengraphics.com) + Keith Whitwell, Tungsten Graphics, Inc. (keith 'at' tungstengraphics.com) + +Status + + Shipping (Mesa 4.0.4 and later) + +Version + + 1.0 + +Number + + TBD + +Dependencies + + OpenGL 1.0 or later is required + This extensions is written against the OpenGL 1.4 Specification. + +Overview + + This extension adds a new pixel storage parameter to indicate that + images are to be packed in top-to-bottom order instead of OpenGL's + conventional bottom-to-top order. Only pixel packing can be + inverted (i.e. for glReadPixels, glGetTexImage, glGetConvolutionFilter, + etc). + + Almost all known image file formats store images in top-to-bottom + order. As it is, OpenGL reads images from the frame buffer in + bottom-to-top order. Thus, images usually have to be inverted before + writing them to a file with image I/O libraries. This extension + allows images to be read such that inverting isn't needed. + +IP Status + + None + +Issues + + 1. Should we also define UNPACK_INVERT_MESA for glDrawPixels, etc? + + Resolved: No, we're only concerned with pixel packing. There are other + solutions for inverting images when using glDrawPixels (negative Y pixel + zoom) or glTexImage (invert the vertex T coordinates). It would be easy + enough to define a complementary extension for pixel packing in the + future if needed. + +New Procedures and Functions + + None + +New Tokens + + Accepted by the <pname> parameter of PixelStorei and PixelStoref + and the <pname> parameter of GetIntegerv, GetFloatv, GetDoublev + and GetBooleanv: + + PACK_INVERT_MESA 0x8758 + +Additions to Chapter 2 of the OpenGL 1.4 Specification (OpenGL Operation) + + None + +Additions to Chapter 3 of the OpenGL 1.4 Specification (Rasterization) + + None + +Additions to Chapter 4 of the OpenGL 1.4 Specification (Per-Fragment +Operations and the Frame Buffer) + + Add the following entry to table 4.4 (PixelStore parameters) on page 182: + + Parameter Name Type Initial Value Valid Range + --------------------------------------------------------- + PACK_INVERT_MESA boolean FALSE TRUE/FALSE + + In the section labeled "Placement in Client Memory" on page 184 + insert the following text into the paragraph before the sentence + that starts with "If the format is RED, GREEN, BLUE...": + + "The parameter PACK_INVERT_MESA controls whether the image is packed + in bottom-to-top order (the default) or top-to-bottom order. Equation + 3.8 is modified as follows: + + ... the first element of the Nth row is indicated by + + p + Nk, if PACK_INVERT_MESA is false + p + k * (H - 1) - Nk, if PACK_INVERT_MESA is true, where H is the + image height + " + +Additions to Chapter 5 of the OpenGL 1.4 Specification (Special Functions) + + None + +Additions to Chapter 6 of the OpenGL 1.4 Specification (State and +State Requests) + + None + +Additions to Appendix A of the OpenGL 1.4 Specification (Invariance) + + None + +Additions to the AGL/GLX/WGL Specifications + + None + +GLX Protocol + + None + +Errors + + None + +New State + + Add the following entry to table 6.20 (Pixels) on page 235: + + Get Value Type Get Cmd Initial Value Description Sec Attribute + -------------------------------------------------------------------------------------------------- + PACK_INVERT_MESA boolean GetBoolean FALSE Value of PACK_INVERT_MESA 4.3.2 pixel-store + +Revision History + + 21 September 2002 - Initial draft |