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 53d5fca71..0eeb58c13 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 defined 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
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