Added mechanism to predefine associated macros for extensions. Also refactore...

Added mechanism to predefine associated macros for extensions. Also refactored the way extension behavior is initialized and updated.
Please note that I still need to add validation that appropriate extensions are enabled before using an extension function.
BUG=25

[dgkoch, 2010-09-03 11:59:27]

looks largely ok, just the one comment.

Daniel

http://codereview.appspot.com/2139042/diff/1/4
File src/compiler/Initialize.cpp (right):

http://codereview.appspot.com/2139042/diff/1/4#newcode626
src/compiler/Initialize.cpp:626: extBehavior["GL_OES_standard_derivatives"] =
EBhDisable;
Not quite sure I follow the logic here.  Shouldn't all extensions always be
disabled by default until explicitly enabled, and even then that should only be
allowed when resources.<extname> has been enabled in the compiler?

[Alok Priyadarshi, 2010-09-03 16:21:09]

http://codereview.appspot.com/2139042/diff/1/4
File src/compiler/Initialize.cpp (right):

http://codereview.appspot.com/2139042/diff/1/4#newcode626
src/compiler/Initialize.cpp:626: extBehavior["GL_OES_standard_derivatives"] =
EBhDisable;
On 2010/09/03 11:59:27, dgkoch wrote:
> Not quite sure I follow the logic here.  Shouldn't all extensions always be
> disabled by default until explicitly enabled, and even then that should only
be
> allowed when resources.<extname> has been enabled in the compiler?

Isn't that exactly what I am doing here?

[dgkoch, 2010-09-03 16:26:20]

http://codereview.appspot.com/2139042/diff/1/4
File src/compiler/Initialize.cpp (right):

http://codereview.appspot.com/2139042/diff/1/4#newcode626
src/compiler/Initialize.cpp:626: extBehavior["GL_OES_standard_derivatives"] =
EBhDisable;
On 2010/09/03 16:21:12, alokp wrote:
> On 2010/09/03 11:59:27, dgkoch wrote:
> > Not quite sure I follow the logic here.  Shouldn't all extensions always be
> > disabled by default until explicitly enabled, and even then that should only
> be
> > allowed when resources.<extname> has been enabled in the compiler?
> 
> Isn't that exactly what I am doing here?

You are only doing that if resources.OES_standard_derivatives has been set (ie
support for this extension has been enabled). If the extension is not enabled,
won't it leave this uninitialized?  In other words, do we actually need line 625
here?

[Alok Priyadarshi, 2010-09-03 17:19:22]

http://codereview.appspot.com/2139042/diff/1/4
File src/compiler/Initialize.cpp (right):

http://codereview.appspot.com/2139042/diff/1/4#newcode626
src/compiler/Initialize.cpp:626: extBehavior["GL_OES_standard_derivatives"] =
EBhDisable;
 > You are only doing that if resources.OES_standard_derivatives has been set
(ie
> support for this extension has been enabled). If the extension is not enabled,
> won't it leave this uninitialized?  In other words, do we actually need line
625
> here?
> 

Yes we do. If resources.OES_standard_derivatives is not set we do not put an
entry for "GL_OES_standard_derivatives" in extBehavior (which is a map). If a
shader tries to enable an extension, we try to find and update the behavior. If
an entry is not found we just issue a warning that this extension is not
supported.

In summary InitExtensionBehavior adds entries for supported extensions only.

[dgkoch, 2010-09-03 18:01:46]

Ok. Thanks for clarifying.

No issues from me then.
Daniel