[Freetype] Re: [Devel] FT_Set_Transform more info

[David Turner]

Hi Mike,

> 
> Thanks for your help. Speaking of small bitmap cache, what is the difference 
> between that and the Image cache and when would I use one verses the other?
> Thanks again.
>

the "normal" cache is used to store FT_Glyph objects, which can be
FT_OutlineGlyph or FT_BitmapGlyph objects depending on their face
descriptor / load flags.

the "small bitmap" cache is ideal when you only need to cache small
glyph bitmaps (i.e. with width and height < 256, and bearings in the
-128..127 range), because it uses much less memory per glyph than
a single FT_BitmapGlyph.

This means that for a constant "cache memory pool", you'll be able
to hold more glyphs, thus improving your overall performance..

A typical application should  use both cache, and discriminate
between them with the character pixel size used. I believe that
it's what the "ftview" program does by the way..

All of this isn't really documented yet, because I have not
completely finished the glyph sub-system (even if the current
code works pretty well); some other priorities also keep me
busy :-)

Cheers,

- David