[Mesa-dev] [PATCH 2/2] mesa: rearrange texture error checking order

[Brian Paul]

On 07/23/2015 04:37 PM, Ilia Mirkin wrote:
> On Thu, Jul 23, 2015 at 6:34 PM, Brian Paul <brianp at vmware.com> wrote:
>> On 07/23/2015 04:24 PM, Ilia Mirkin wrote:
>>>
>>> On Wed, Jul 22, 2015 at 1:44 PM, Brian Paul <brianp at vmware.com> wrote:
>>>>
>>>> On 07/22/2015 11:29 AM, Ilia Mirkin wrote:
>>>>>
>>>>>
>>>>> On Wed, Jul 22, 2015 at 1:20 PM, Brian Paul <brianp at vmware.com> wrote:
>>>>>>
>>>>>>
>>>>>> On 07/22/2015 11:02 AM, Ilia Mirkin wrote:
>>>>>>>
>>>>>>>
>>>>>>>
>>>>>>> This moves the width/height/depth == 0 check to the front and avoids
>>>>>>> doing any other checking when that is the case.
>>>>>>>
>>>>>>> Also moves the dimensions check after the format/type checks so that
>>>>>>> we
>>>>>>> don't bail out with success on a width/height/depth == 0 request when
>>>>>>> the format/type don't match.
>>>>>>>
>>>>>>> Bugzilla:
>>>>>>>
>>>>>>>
>>>>>>> https://urldefense.proofpoint.com/v2/url?u=https-3A__bugs.freedesktop.org_show-5Fbug.cgi-3Fid-3D91425&d=BQIBAg&c=Sqcl0Ez6M0X8aeM67LKIiDJAXVeAw-YihVMNtXt-uEs&r=T0t4QG7chq2ZwJo6wilkFznRSFy-8uDKartPGbomVj8&m=Y1TotaJmX1E7sCopvmMJc8PQKFXlHu6QxfcYOydKuII&s=L0lmmuk31G6M4hZEiwnX-IC4CPhW7rsrSCgEYtDgXjw&e=
>>>>>>> Signed-off-by: Ilia Mirkin <imirkin at alum.mit.edu>
>>>>>>
>>>>>>
>>>>>>
>>>>>>
>>>>>> I suspect this isn't really needed in light of my patch to
>>>>>> getteximage-invalid-format-for-packed-type.c
>>>>>>
>>>>>> I believe the test was in error, or at least sloppy, in that it was
>>>>>> calling
>>>>>> glGetTexImage to test format/type validation when there wasn't even a
>>>>>> texture image to return.  The OpenGL spec doesn't specify an order for
>>>>>> error
>>>>>> checking multiple things, so if there's multiple errors, you can't be
>>>>>> sure
>>>>>> which one will be reported first.  My patch to the test removes that
>>>>>> ambiguity.
>>>>>
>>>>>
>>>>>
>>>>> Well, irrespective of the piglit test, the current code is a little
>>>>> suspect -- it does the width/height/depth == 0 checks after it ensures
>>>>> that height == 1 for 1d and depth == 1 for 2d. Any thoughts on that?
>>>>
>>>>
>>>>
>>>> Yeah, that makes sense.  I guess we don't have any tests that exercise
>>>> getting a 0 x 0 texture image.
>>>>
>>>> Reviewed-by: Brian Paul <brianp at vmware.com>
>>>
>>>
>>> Ugh, so Dylan points out that this breaks
>>>
>>> bin/arb_direct_state_access-get-textures
>>>
>>> (which I didn't notice, because I guess it got recently enabled on mesa)
>>>
>>> It has this check:
>>>
>>>           /* No Storage
>>>            *
>>>            * The spec doesn't say what should happen in this case.  This is
>>>            * addressed by Khronos Bug 13223.
>>>            */
>>>           glCreateTextures(GL_TEXTURE_CUBE_MAP, 1, &name);
>>>           glGetTextureImage(name, 0, GL_RGBA, GL_UNSIGNED_BYTE, 0, data);
>>>           pass &= piglit_check_gl_error(GL_INVALID_OPERATION);
>>>           glDeleteTextures(1, &name);
>>>
>>> But my width == 0 || ... check at the top of dimensions_error_check
>>> short-circuits all that.
>>>
>>> Brian, what situation is the "width == 0 || height == 0 || depth == 0"
>>> supposed to account for?
>>
>>
>> After error checking, it just lets up skip all the
>> ctx->Driver.GetTexSubImage() calls and associated stuff (mapping PBOs, etc).
>
> But some of the error checking makes sure that width/height/depth
> aren't 0. And in case of a missing image, width/height/depth are all
> set to 0. That was my confusion.

OK, it looks like we can remove the height==1 and depth==1 checks. 
NVIDIA's driver does not generate an error if height=0 or depth=0 in the 
1D/2D cases.

Can you take care of that?

-Brian