"
Hi Mike,
I just noticed the request for info on the OpenGL 1.4 update included
in 10.2.3. John Stauffer posted the following comprehensive details to the OpenGL developers list, as this is basically a public list, I'm
sure it's fine to pass the info on :)
One point that should be made clear, is that no currently shipping mac
video card fully supports all the features of OpenGL 1.4 in hardware.
More info on OpenGL 1.4 can be found at opengl.org, specifically this
pdf:
www.opengl.org/developers/documentation/version1_4/glspec14.pdf
Cheers
Ben Boffey
MacOS X 10.2.3 delivers OpenGL 1.4 and 13 new extensions.
* 13 New Extensions
GL ARB shadow ambient
GL EXT s3tc texture compression
GL EXT shadow funcs
GL EXT stencil two side
GL ARB fragment program
GL ARB vertex blend
GL ARB window pos
GL EXT multi draw arrays
GL NV light max exponent
GL SGIS generate mipmap
GL Apple float pixels
GL ATI point cull
GL ATI texture mirror once
OpenGL version 1.4, released on July 24, 2002, is the fourth revision
since the original version 1.0. Version 1.4 is upward compatible with
earlier versions, meaning that any program that runs with a 1.3, 1.2,
1.1, or 1.0 GL implementation will also run unchanged with a 1.4 GL
implementation. In addition to numerous additions to the classical
fixed-function GL pipeline in OpenGL 1.4, the OpenGL ARB also approved
the ARB vertex program extension, which supports programmable vertex
processing. Following are brief descriptions of each addition to
OpenGL 1.4:
* Automatic Mipmap Generation - Setting the texture parameter GENERATE
MIPMAP to TRUE introduces a side effect to any modification of the
levelbase of a mipmap array, wherein all higher levels of the mipmap
pyramid are recomputed automatically by successive filtering of the
base level array.
* Blend Squaring extends the set of supported source and destination
blend functions to permit squaring RGB and alpha values during
blending.
* Changes to the Imaging Subset to include BlendEquation, BlendColor,
and the BlendFunc modes CONSTANT COLOR, ONE MINUS CONSTANT COLOR,
CONSTANT ALPHA, and ONE MINUS CONSTANT ALPHA (these features
previously were available only in the optional imaging subset in
versions 1.2 and 1.3 of the GL.)
* Depth and Shadows - Depth textures define a new texture internal
format, DEPTH, normally used to represent depth values. Applications
include image-based shadow casting, displacement mapping, and
image-based rendering. Image-based shadowing is enabled with a new
texture application mode defined by the parameter TEXTURE COMPARE MODE.
* Fog Coordinates can be used in computing fog for a fragment, instead
of using eye distance to the fragment, useful for more complex fog
models
* Multiple Draw Arrays - Multiple primitives may be drawn in a single
call using the MultiDrawArrays and MultiDrawElements commants.
* Point Parameters support additional geometric characteristics of
points, allowing the size of a point to be affected by linear or
quadratic distance attenuation, and increasing control of the mapping
from point size to raster point area and point transparency. This
effect may be used for distance attenuation in rendering particles or
light points.
* Secondary Color may be varied even when lighting is disabled by
specifying it as a vertex parameter with the SecondaryColor commands.
* Separate Blend Functions allow independent setting of the RGB and
alpha blend functions for blend operations that require source and
destination blend factors.
* Stencil Wrap operations INCR WRAP and DECR WRAP allow the stencil
value to wrap around the range of stencil values instead of saturating
to the minimum or maximum values on decrement or increment.
* Texture Crossbar Environment Mode extends the texture combine
environment mode COMBINE by allowing use of the texture color from
different texture units as sources to the texture combine function.
* Texture LOD Bias may be set to bias the computed lamda parameter
used in texturing for mipmap level of detail selection, providing a
means to blur or sharpen textures. LOD bias may be used for depth of
field and other special visual effects, as well as for some types of
image processing.
* Texture Mirrored Repeat extends the set of texture wrap modes with
the mode MIRRORED REPEAT. This effectively defines a texture map twice
as large as the original texture image in which the additional half,
for each mirrored texture coordinate, is a mirror image of the
original texture. Mirrored repeat can be used seamless tiling of a
surface.
* Window Raster Position - The raster position may be set directly to
specified window coordinates with the WindowPos commands, bypassing
the transformation applied to RasterPos.
