cc: Cache highp_threshold in TexCoordPrecisionRequired

cc: Cache highp_threshold in TexCoordPrecisionRequired

BUG=237418
Committed: https://src.chromium.org/viewvc/chrome?view=rev&revision=198698

[vangelis, 2013-05-03 19:13:27]

https://codereview.chromium.org/14705008/diff/1/cc/output/shader.cc
File cc/output/shader.cc (right):

https://codereview.chromium.org/14705008/diff/1/cc/output/shader.cc#newcode102
cc/output/shader.cc:102: DCHECK_EQ(s_cached_context, context);
It's not uncommon for one renderer to have multiple contexts instantiated so
this assert will trigger. The real check would be whether they would return
different results but I suspect that'd be rare.

I'd also be a bit concerned about caching a pointer context into a static (just
for doing this assert). Maybe skip it overall?

[brianderson, 2013-05-03 21:56:59]

ptal.

I removed the DCHECK and made the code multi-thread/context safe.

The cache is now provided by the caller of the function and it is the
responsibility of the caller to clear the cache if it is using a different
context.

[vangelis, 2013-05-03 22:08:33]

https://codereview.chromium.org/14705008/diff/19001/cc/output/shader.cc
File cc/output/shader.cc (right):

https://codereview.chromium.org/14705008/diff/19001/cc/output/shader.cc#newco...
cc/output/shader.cc:85: if (*highp_threshold_cache == 0) {
I think you'll need to add: 
|| *highp_threashold_cache > highp_threshold_min

to guard against having this function called with a lower highp_threshold_min
after the result is cached.

https://codereview.chromium.org/14705008/diff/19001/cc/output/shader.cc#newco...
cc/output/shader.cc:91: static GLint precision = 10;
Do these need to be static?

[brianderson, 2013-05-03 22:19:02]

On 2013/05/03 22:08:33, vangelis wrote:
> https://codereview.chromium.org/14705008/diff/19001/cc/output/shader.cc
> File cc/output/shader.cc (right):
> 
>
https://codereview.chromium.org/14705008/diff/19001/cc/output/shader.cc#newco...
> cc/output/shader.cc:85: if (*highp_threshold_cache == 0) {
> I think you'll need to add: 
> || *highp_threashold_cache > highp_threshold_min
> 
> to guard against having this function called with a lower highp_threshold_min
> after the result is cached.
> 

Although the min is not supposed to change, that is a good point. Will fix.

>
https://codereview.chromium.org/14705008/diff/19001/cc/output/shader.cc#newco...
> cc/output/shader.cc:91: static GLint precision = 10;
> Do these need to be static?

They should not be static. Will fix.

[brianderson, 2013-05-06 20:01:36]

PTAL. Try failures are unrelated to this patch.

[vangelis, 2013-05-06 21:14:22]

lgtm

[commit-bot: I haz the power, 2013-05-06 21:43:39]

CQ is trying da patch. Follow status at
https://chromium-status.appspot.com/cq/brianderson@chromium.org/14705008/32001

[commit-bot: I haz the power, 2013-05-07 12:54:05]

Change committed as 198698