freetype-devel
[Top][All Lists]
Advanced

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

Re: [ft-devel] Fast bisecting BBox_Cubic_Check


From: Alexei Podtelezhnikov
Subject: Re: [ft-devel] Fast bisecting BBox_Cubic_Check
Date: Wed, 27 Feb 2013 07:14:32 -0500


> The new code is a bit worse but faster. The problem is in the
> rounding.  I can potentially scale up the outlines temporarily to
> deal with this problem.

I really wonder whether it makes sense to speed up the exact bbox
computation if this causes a loss of precision.

The original motivation was to kill the last use of FT_SqrtFixed. Then I read old emails that made perplexing assertion that bisection is too slow to converge while never questioning iterations in the sqrt algorithm. So I saw a challenge and produced a fast proof-of-concept code without sqrt. It is a matter of improving accuracy now. The old algorithm uses upscaling to achieve its precision and so can I.

reply via email to

[Prev in Thread] Current Thread [Next in Thread]