Re: Slow Cocoa
Re: Slow Cocoa
- Subject: Re: Slow Cocoa
- From: Public Look <email@hidden>
- Date: Mon, 16 Feb 2004 17:58:51 -0500
In general, allocating and deallocating objects is very expensive. It
is all built on top of malloc() and free(), and at least historically,
both functions were very slow on Unix systems. How slow ? I don't
know. I haven't measured their performance with repeated small
allocations and deallocations on Mac OS X. On a particular opensource
Unix like system I have been using but won't name, malloc() calls
average about a microsecond per call which really adds up... If you
need to allocate a 1 million objects per second, you better not be
doing anything else on that platform.
Note: even reusing the same NSBezierPath instance may not save
allocations because for all we know, NSBezierPath internally allocates
and deallocates storage for the paths you create.
On Feb 16, 2004, at 5:39 PM, Tregaskis, Wade wrote:
I am making an app that draws using Quartz. I used to use the C
functions, but then I started using NSBezierPath. When I tried that
everything was slower. I am guessing this is because of the
messaging.
Is there a way to "speed up" objc?
First question: are you keeping the bezierpath around, or creating a
new one every time -drawRect: is called?
Off the top of your head, what's the performance difference between
creating a new bezier path for each drawing, and keeping one around
and manipulating it via transforms or some similar mechanism? Is it a
2x or 3x benefit, or are we talking orders of magnitude?
Wade Tregaskis
_______________________________________________
cocoa-dev mailing list | email@hidden
Help/Unsubscribe/Archives:
http://www.lists.apple.com/mailman/listinfo/cocoa-dev
Do not post admin requests to the list. They will be ignored.
_______________________________________________
cocoa-dev mailing list | email@hidden
Help/Unsubscribe/Archives:
http://www.lists.apple.com/mailman/listinfo/cocoa-dev
Do not post admin requests to the list. They will be ignored.