[Mesa3d-users] Questions about using Mesa3d for pure SW rendering on Windows.

[Stephane R. <ro...@ca...>]

Hi,

I'm devopping a command line program on Windows.
I have to write code (C++) to rasterize vector data (3d polygons and
polylines). The code will be used to produce images for GIS where the
RGB components a not representing a color, but another attribute (can be
for example an height map where the Intensity component is an altitude
in centimeters between 0 (sea level) and 885000 (Everest height in cm)
). I cannot have a lost in precision.=20

As a first idea, I wanted to use OpenGL (using the OpenGL implementation
and drivers from my Windows OS).=20
But I can't because I need to be able to handle RGBA pixel format at
least 16bits per channel and Grayscale pixelformat > 16bits per channel,
and some graphic card manufacturers drivers are internally "truncating"
the channel values for faster computation. I cannot afford loosing
precision.=20

I need to render the scene offscreen (command line application without
window) with and without antialiasing.=20
I read in the ML archive that there is no antialiasing done in SW. I can
bypass that by generating a bigger image and resizing it down using a
filter (box or gaussian).

Here are my questions :
Does Mesa3d supports vertex and pixel shaders in software ?
If I'm using mesa3d for processing a pixel format setting CHAN_BITS to
16 or 32 in config.h, can I be sure that the computation is really done
with this precision ? (not truncated to 8 bits internally for example)=20
Is Mesa3d SW suitable for my needs ?

Thanks a lot in advance,

Stephane Routelous
http://www.exotk.org