Radeon R600g Finally Catching Up With OpenGL 4

[phoronix]

Phoronix: Radeon R600g Finally Catching Up With OpenGL 4

Landing tonight within Mesa Git master is ARB_gpu_shader5 support in the Radeon R600g driver...

http://www.phoronix.com/scan.php?page=news_item&px=R600g-Almost-GL41

[RussianNeuroMancer]

I guess we need fp64 emulation for hardware that doesn't supports it.

[dungeon]

I guess we need fp64 emulation for hardware that doesn't supports it.

I guess that is not top priority as people could just fake it in hope some app will not used it of course... but even if it does and it is already emulated, it will be probably so slow to made any sense

[SvenK]

Can someone tell me where to find the Documents for Barts?

[dungeon]

Can someone tell me where to find the Documents for Barts?

Here are some links:

http://xorg.freedesktop.org/wiki/RadeonFeature/#index10h2

For Barts i think you should read Evergreen docs mostly.

[RussianNeuroMancer]

I guess that is not top priority as people could just fake it in hope some app will not used it of course... but even if it does and it is already emulated, it will be probably so slow to made any sense

Then no out-of-the-box support for latest ports (that require OGL4.0+) by r600g driver.

[zakhrov]

David Airlie already stated that for fp64 to be supported on other Evergreen cards there needs to be a "softfloat" implementation
that uses unsigned 32bit integers to fake fp64

[smitty3268]

Then no out-of-the-box support for latest ports (that require OGL4.0+) by r600g driver.

Well, no. Some GPUs with the r600g driver would support it. Just not all of them.

Most of the high end cards (at their time of release) have native support. The lower and medium end cards do not.

I have a strong suspicion those cards would struggle to be playable with any port requiring GL4 features anyway. So far they've tended to be rather inefficient ports compared to the original DX games, and I think the porters are assuming you have more modern hardware with extra speed to spare.

Regardless, I think it might make sense to just have the driver expose GL4 support even without softfloat, because I simply don't think that there are any apps out there that actually use fp64 in OpenGL.

It would be lying to the app, of course, but such things have been done before in the name of expediency. Such as r300 hardware exposing GL2 even though it doesn't support npot textures. Or software drivers exposing GL3 without MSAA support.

[dungeon]

Then no out-of-the-box support for latest ports (that require OGL4.0+) by r600g driver.

So what you think is the best, when hardware does not have support... to me that is about it . You can only fake it, one way or another .

[jf33]

The driver should not lie about supported features by default. Instead, there should be an option to manually do this by setting an environment variable.