On 07/26/2013 02:20 PM, Kenneth Graunke wrote:
Hello all,
I've been looking at https://bugs.freedesktop.org/show_bug.cgi?id=59150
and could use your opinion.
OpenGL defines two equations for converting from SNORM to floating point
data. These are:
f = (2c + 1)/(2^b - 1)
D3D10 specifies equation 2.3 (and I'm sure so that D3D9). So probably all
hardware can handle it.
I'm surprised that formula 2.2 even exists, and that OpenGL could have been so
lax about it.
Jose
- Original Message -
Hello all,
I've been looking at
That formula 2.2 existed for quite some time and was only used for
vertex specification.
And then came along textures using that format, and in good OpenGL
tradition the old formula was kept for vertex data (I guess the new
formula was used for textures because that was what hardware and other
Hello all,
I've been looking at https://bugs.freedesktop.org/show_bug.cgi?id=59150
and could use your opinion.
OpenGL defines two equations for converting from SNORM to floating point
data. These are:
f = (2c + 1)/(2^b - 1)(equation 2.2)
f = max{c/2^(b-1) - 1), -1.0}
What are other implementations doing?
IIRC, GL3-class NV hardware passes the current piglit tests.
On Sat, Jul 27, 2013 at 9:20 AM, Kenneth Graunke kenn...@whitecape.org wrote:
Hello all,
I've been looking at https://bugs.freedesktop.org/show_bug.cgi?id=59150 and
could use your opinion.
On R600 (GL3-class), we can choose which equation will be used,
because it's a state that is part of the resource descriptor. Not sure
about later chipsets, but the vertex fetching must be done in a shader
anyway, therefore we can quite easily implement any format conversion.
As far as OpenGL is
