[boost] Re: Re: Vector graphics: Anti-Grain Geometry, second round

From: Maxim Shemanarev (mcseem_at_[hidden])
Date: 2002-04-23 00:00:49

Hi Joel,

Here're some answers:

> I wanted to know some details but I get dead links.
Sorry about that. However, you can download the current snapshot and read
some comments inside the .h files. Try to build the examples (if
Win-platform with VC++ is available).

> 1] how it does the "cross-platform" rendering
It uses a rendering buffer in memory which is to be displayed. How it can be
displayed is up to you. The only dependence here is the pixel format (RGB,
ARGB, BGR, BGRA,
8 bit per component, 5-5-5 format, 5-6-5 and so on). But AGG will have
render classes (very simple) for all the most popular formats.

> 2] how fast is it in rendering text compared to direct platform facilities
Actually, the main rendering algorithm is based on David Turner's idea who
created font rendering engine FreeType - www.freetype.org. I improved his
algorithm and tried to use all possible C++ benefits to get better
performance. My version works about 20-30% faster than his original one. So,
at least, it should be not worse than FreeType which is used all over the
Linux world. As for the MS font rendering engine - I've no idea yet,
probably slower, but not dramatically.

> 3] how capable it is in doing real time 2D interactive animation.
It depends. It will be slower than modern graphic accelerators, but the
question is can it be appropriate for you? For example, when rendering not
very complicated scenes, about 30-40% of time is spent in Windows displaying
function StretchDIBits. DirectX displays bitmaps much faster, so the overall
performance depends on it Again, try to build the examples and estimate the
performance.

McSeem
http://www.antigrain.com