[webkit-dev] Running pixel tests on build.webkit.org

[Maciej Stachowiak]

On Jan 9, 2010, at 6:35 AM, Nikolas Zimmermann wrote:

>
> Am 08.01.2010 um 22:32 schrieb Evan Martin:
>
>> On Thu, Jan 7, 2010 at 4:05 PM, Nikolas Zimmermann
>> <zimmermann at physik.rwth-aachen.de> wrote:
>>> How about we'd start only with svg/ pixel tests? Getting SVG pixel  
>>> tests
>>> working across the ports
>>> would be a huge leap forward.
>>
>> One caveat: at least on Linux Chrome we've found that we get slightly
>> different pixel results for some SVG tests in curves depending on
>> whether we're 64 or 32-bit.  It problem could be in Skia, though.
>>
>> You should pick whether your baselines are gonna be 32 or 64 and then
>> add exceptions for the other; in Chrome we didn't notice we were
>> mixing for a while and rebaselined some results over themselves a few
>> times.
>
> I am partly aware of this problem (regarding 64 vs 32. bit) it  
> affects non-linux platforms as well,
> the root of the issue is that Path::debugString() does NOT have an  
> cross-platform implementation,
> but instead every platform manually dumps the path elements. For CG  
> we see 0.0 vs -0.0 differences
> for certain paths - the whole problem is easily fixable though.  
> Anyone wants to volunteer? :-)

What does it take to fix it?

Also, I believe that 0.0 vs. -0.0 in a path will never actually result  
in different layout. And I don't believe this has ever identified a  
real bug. So perhaps we should dump all zeros as positive 0.

Regards,
Maciej