Gradients are broken with glamor when RepeatReflect is set

[Michel Dänzer]

On 2018-01-23 05:36 PM, Jeffrey Smith wrote:
> On Tue, Jan 23, 2018 at 10:27 AM, Michel Dänzer <michel at daenzer.net> wrote:
>> On 2018-01-23 04:26 PM, Chris Wilson wrote:
>>> Quoting Jeffrey Smith (2018-01-23 15:15:10)
>>>> On Mon, Jan 22, 2018 at 3:01 PM, Chris Wilson <chris at chris-wilson.co.uk> wrote:
>>>>> Quoting Adam Jackson (2018-01-22 20:09:52)
>>>>>> On Sat, 2017-12-23 at 19:26 +0100, Clemens Eisserer wrote:
>>>>>>> Hi there,
>>>>>>>
>>>>>>> Glamor's gradient acceleration code is broken in case RepeatReflect is
>>>>>>> used, please see: https://bugs.freedesktop.org/show_bug.cgi?id=98508
>>>>>>> I've filed the bug report over a year ago, but except for a
>>>>>>> confirmation from Michel Dänzer nothing happend.
>>>>>>>
>>>>>>> Unfourntunatly I lack the expertise to fix it myself - however instead
>>>>>>> of leaving it broken forever, could we fall back to software for
>>>>>>> RepeatReflect.
>>>>>>> I guess slow is better than completly broken?
>>>>>>
>>>>>> Just want to note that this isn't forgotten. I got as far as testing
>>>>>> the reproducer with Xephyr and verifying glamor was wrong and fb was
>>>>>> right, but don't yet get what the RepeatReflect math is getting wrong.
>>>>>> I'll definitely have a fix for 1.20 one way or another, but that may
>>>>>> just be forcing a fallback.
>>>>>>
>>>>>> If anyone wanted to investigate this, I think this is the guilty
>>>>>> conditional:
>>>>>>
>>>>>> https://cgit.freedesktop.org/xorg/xserver/tree/glamor/glamor_gradient.c#n296
>>
>> It's broken with llvmpipe/softpipe as well. Does it render correctly
>> with glamor on i965? If so, maybe it's a Gallium non-driver issue.
> 
> I haven't had a chance to do any testing with the testcase code.
> Is it possible to get images of the actual vs expected output?
> Perhaps attached to the bug report.

I attached images of the good and bad output to the bug report.


-- 
Earthling Michel Dänzer               |               http://www.amd.com
Libre software enthusiast             |             Mesa and X developer