Re: [Freetype] Transformation Matrix has no effect of SFNT embedded bitmaps

[Detlef Würkner]

address@hidden (Farhad Khalafi) wrote:

> When TT_CONFIG_OPTION_EMBEDDED_BITMAPS is selected and a rotation matrix
> is defined using FT_Set_Transform() function, for certain font sizes,
> the matrix is ignored.
> 
> My understanding is that if an embedded SFNT bitmap is found, then it is
> used in TT_Load_Glyph(). The outline array is then empty and
> transformation is not applied. I used MSGothic.TTC with glyph index of
> 14818 for my test.
> 
> If I comment out TT_CONFIG_OPTION_EMBEDDED_BITMAPS in the option file,
> then the problem is resolved at all font sizes.
> 
> My question is:
> 
> What are the implications of disabling the embedded bitmaps? Are there
> always outline-based alternatives to the bitmaps, or is this going to
> restrict supporting of certain font files?
> 
> I use the latest released version (2.1.9) of FreeType library.
> 
> Any clarification will be appreciated.

When you know in advance that you want to apply a rotation matrix to the
loaded glyph, just set the flag

  *   FT_LOAD_NO_BITMAP ::
  *     Don't look for bitmaps when loading the glyph.  Only scalable
  *     outlines will be loaded when available, and scaled, hinted, or
  *     rendered depending on other bit flags.
  *
  *     This does not prevent you from rendering outlines to bitmaps
  *     with @FT_LOAD_RENDER, however.
  *

and dont set it when you know in advance you dont want to apply any
transformation that doesnt work with bitmaps.

Ciao, Detlef
-- 
_ // address@hidden
\X/  Detlef Wuerkner, Langgoens/Germany