Added functor to GrTHashCache to allow discovery of un-reffed resources

Added functor to GrTHashCache to allow discovery of un-reffed resources

[bsalomon, 2012-09-17 19:25:04]

On 2012/09/17 19:06:25, robertphillips wrote:

Rather than a base class and virtual on the functor, perhaps the
GrTHashTable::find function should be templated on the functor type.

[robertphillips, 2012-09-17 19:36:47]

That would make it difficult to access the same cache with different search
mechanisms. For example, usually we want to get texture on a first match basis
but we need to use the more stringent "no other refs" test for uncached
textures.

[bsalomon, 2012-09-17 19:50:19]

On 2012/09/17 19:36:47, robertphillips wrote:
> That would make it difficult to access the same cache with different search
> mechanisms. For example, usually we want to get texture on a first match basis
> but we need to use the more stringent "no other refs" test for uncached
> textures.

I'm not sure I get why it'd be more difficult. The two search classes just
wouldn't share a base class. To me it seems like the choice is either one small
function with a virtual call or two small functions with no virtual calls. Am I
missing something?

[robertphillips, 2012-09-18 15:41:08]

PTAL - I have templatized the find method on the functor's type.

[bsalomon, 2012-09-18 15:49:38]

LGTM w/ some Qs

http://codereview.appspot.com/6503126/diff/11001/src/gpu/GrTHashCache.h
File src/gpu/GrTHashCache.h (right):

http://codereview.appspot.com/6503126/diff/11001/src/gpu/GrTHashCache.h#newco...
src/gpu/GrTHashCache.h:16: // GrTDefaultFindFunctor implements the default find
behavior for

Can this be a local class in the find function?

http://codereview.appspot.com/6503126/diff/11001/src/gpu/GrTHashCache.h#newco...
src/gpu/GrTHashCache.h:41: template <typename FindFuncType> T*  find(const Key&,
const FindFuncType&) const;
just curious, why a functor and not a function (which wouldn't require an
object)? Does the functor have some initial state that can change between
invocations?

[robertphillips, 2012-09-18 17:17:01]

committed as r5587

http://codereview.appspot.com/6503126/diff/11001/src/gpu/GrTHashCache.h
File src/gpu/GrTHashCache.h (right):

http://codereview.appspot.com/6503126/diff/11001/src/gpu/GrTHashCache.h#newco...
src/gpu/GrTHashCache.h:16: // GrTDefaultFindFunctor implements the default find
behavior for
Although it is supposed to work in VS, locally-defined classes are supposedly
forbidden in templates (b.c. they have no linkage)

http://codereview.appspot.com/6503126/diff/11001/src/gpu/GrTHashCache.h#newco...
src/gpu/GrTHashCache.h:41: template <typename FindFuncType> T*  find(const Key&,
const FindFuncType&) const;
You suggested functors a couple of days ago.