[Devel] extending FT_Stream to handle moveable memory

[Graham Asher]

As part of my work for Artifex, Inc., to connect FreeType with GhostScript I
am going to extend FT_Stream so that it can handle blocks of memory that can
move around between calls to FreeType functions. GhostScript stores TrueType
font file images in moveable memory. These changes will enable FT_Open_Face,
which takes an FT_Stream object as one of its arguments, to handle such
fonts.

Please let me know if there is already a way of doing this, which I very
much doubt. I am aware that I could implement this in a much more cumbersome
way using a special FT_StreamRec_::read function, but I don't want to pay
the performance cost of allocating and freeing heap memory when I could
easily get a pointer to the actual memory.

You'll be pleased to know that the changes will be minimal and should have
no impact on performance.

Graham Asher
software architect