Bug 94835

Summary:	Increase fragment shader sample limits from 16 to 32 (AMD Linux - Mesa/RadeonSi)
Product:	Mesa	Reporter:	Edwin Smith (Feral Interactive) <esmith>
Component:	Drivers/Gallium/radeonsi	Assignee:	Default DRI bug account <dri-devel>
Status:	RESOLVED FIXED	QA Contact:	Default DRI bug account <dri-devel>
Severity:	normal
Priority:	medium
Version:	git
Hardware:	All
OS:	Linux (All)
See Also:	https://bugs.freedesktop.org/show_bug.cgi?id=94705 https://bugs.freedesktop.org/show_bug.cgi?id=91951
Whiteboard:
i915 platform:		i915 features:
Bug Depends on:
Bug Blocks:	94705

Description Edwin Smith (Feral Interactive) 2016-04-06 07:05:48 UTC

Please increase fragment shader sample limits from 16 to 32. This is causing serious issues with Company Of Heroes 2 as the engine needs more than 16 samplers to correctly render the floor.

Please note: Mesa support 32 samplers with their Intel drivers, but not AMD. See GL_MAX_TEXTURE_IMAGE_UNITS_ARB in https://people.freedesktop.org/~imirkin/glxinfo/glxinfo.html

Feral can provide a Steam key to active Mesa engineers working on this issue if that would help their progress. YOU should be abel to use Intel Mesa as a reference as that draws correctly as it has a higher texture sampler limit.

Comment 1 Edwin Smith (Feral Interactive) 2016-04-06 07:10:38 UTC

Added links to:

94705 - CoH2 specific bug logged by an end user showing the side effect if the sampler limit is reached on AMD. 

91951 - Unsure if exactly the same issue but potentially a similar root cause. This was logged agains ARMA 3 developer by another developer so I have no insight other than finding the bug when looking for duplicates before logging.

Comment 2 Ilia Mirkin 2016-04-06 13:47:29 UTC

(In reply to Edwin Smith from comment #0)
> Feral can provide a Steam key to active Mesa engineers working on this issue
> if that would help their progress.

A little bit off-topic, but would such a key be provided for people working on drivers other than radeonsi? [r600 and nvc0 come to mind]

> YOU should be abel to use Intel Mesa as a
> reference as that draws correctly as it has a higher texture sampler limit.

By the way, that's only true for Haswell and newer. Ivybridge (gen7) is limited to 16, at least on Mesa.

Comment 3 Nicolai Hähnle 2016-04-06 17:03:37 UTC

I have a preliminary patch set for this, but I still need to put it through its testing paces.

Comment 4 Edwin Smith (Feral Interactive) 2016-04-07 12:46:25 UTC

(In reply to Ilia Mirkin from comment #2)
> (In reply to Edwin Smith from comment #0)
> > Feral can provide a Steam key to active Mesa engineers working on this issue
> > if that would help their progress.
> 
> A little bit off-topic, but would such a key be provided for people working
> on drivers other than radeonsi? [r600 and nvc0 come to mind]

Any reasonable request from an engineer working on this issue requesting a key to help with their efforts will be considered.

Comment 5 Nicolai Hähnle 2016-04-07 18:18:26 UTC

Implemented in Git master commit 2abe4f8d7dcdcff75c28958e1a691ebf6cdee1ac

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