Re: Another small optimization: aglMacro

[James W. W. <os...@jw...>]

On Apr 18, 2004, at 1:48 PM, Dair Grant wrote:

>> However some Quesa internal functions would need an extra
>> parameter.
>
> Plus we'd need extra local variables, if I understand the setup
> correctly, i.e., we'd have to have a local agl_ctx in each routine that
> made a GL call which was initialised to the context in the instance
> data?

No, not really.  For example, to make the change in IRUpdate.c, I added 
the following to the top of the file:

#if QUESA_OS_MACINTOSH
	#define		agl_ctx		((AGLContext)instanceData->glContext)

	#if TARGET_RT_MAC_MACHO
		#include <AGL/aglMacro.h>
	#else
		#include <aglMacro.h>
	#endif
#endif

It so happens that everywhere you need the context, you have an 
instanceData variable by which one can access the GL context.  In some 
other source files, I defined agl_ctx as ((AGLContext)glContext) 
instead.

> A 6% change isn't normally something to ignore, but I'd be curious to
> see if you get any impact in other tests?
>
> The multibox test I'd expect to spend most of its time updating the 
> view
> stack: i.e., showing the cost of per-object processing within Quesa
> rather than rendering time (and a lot of that is probably the bogus 
> view
> state stack updates on pop).
>
> Normally this only really helps for immediate mode drawing, where 
> you're
> doing N-thousand glVertex calls or whatever: as Frank says that's the
> case for the transparent path, but shouldn't happen normally.
>
> So I'm kind of surprised you did get anything out of it actually. :-)
>
>
> -dair (I wonder if the place we're saving the time is in IRUpdate.c: we
> probably make more GL state calls in there than we do GL drawing calls,
> and I bet most of them are happening because of the excessive view 
> state
> stack updates)

There's enough variation in frame rate that it's possible that what I 
thought was an improvement was actually experimental error.  I'll hold 
off on this, and take another look after the view state stack stuff has 
been addressed.
--
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