Mac OS X Porting - Native Fonts
First contact with Herbert Duerr (hdu), about fonts :
Choosen answers to start :
"...I already started an ATSUI port long ago. See issue 23283 for details (http://www.openoffice.org/issues/show_bug.cgi?id=23283). This patch is very old and worked for some simple situations..."
"..Everything is in VCL, especially the vcl/inc/sallayout.hxx header file is important. vcl/*/gdi/ subdirectories might be interesting too.
The SalLayout base class is the core of all VCL-text. It corresponds to an ATSUTextLayout object on ATSUI. All text display, measurements, text breaking, glyph fallback etc. are done via SalLayout objects.."
"..I think the best way is to deeply understand a SalLayout object is to get to know the very old VCL OutputDevice text related methods, and especially what the pDXArray parameter in them means. Then learn ATSUI, Uniscribe, ICU's layout engine and Java's TextLayout really well. A SalLayout is just the abstracted combination of all these layout engines. A SalLayout object has the "old pDXArray flavour" to keep the changes required by the rest of OOo minimal.."
"..Well, changing anything in the VCL text core is very hard, because it impacts basically everything text related in OOo. Since a simple change there can easily break some use cases, several scripts, platforms and may have a bad performance impact, I'd rather not change anything in the core...
"...If it is possible to isolate it to just the file salatslayout.cxx provided in issue 23283 then I'm all for it.."
Fixme : documentation starting point :
interesting documents about design of fonts implementations in OpenOffice.org :
http://gsl.openoffice.org/files/documents/16/1890/OOo_Glossary_Of_Font_Terms.htm
Font management concept : http://gsl.openoffice.org/files/documents/16/1603/vcl_new_fontmanagement.pdf
window class hierarchy :
http://gsl.openoffice.org/files/documents/16/974/VCLClassHierarchyWindows.sxd
Contents
SalLayout base class description
[FIXME]
salatslayout.cxx description
sal : means System Abstraction Layer
ats : Apple Type Server native font server
ATSUI : Apple Type Server for Unicode Imagery
layout : for the asbtraction
deprecated functions in Carbon API
ATSUCreateTextLayoutWithTextHandle ATSUSetTextHandleLocation ATSUSetFontFallbacks ATSUGetFontFallbacks ATSUFONDtoFontID ATSUFontIDtoFOND ATSUGetGlyphInfo ATSUDrawGlyphInfo ATSUIdle
Content description : salatslayout.cxx
URL's & important LINKS
sallayout.hxx description
See : http://wiki.services.openoffice.org/wiki/Sallayout.hxx
Unicode references in Wikipedia
English reference : http://en.wikipedia.org/wiki/Unicode
French reference : http://fr.wikipedia.org/wiki/Unicode
ICU references in Wikipedia
English reference : http://en.wikipedia.org/wiki/International_Components_for_Unicode
French reference : http://fr.wikipedia.org/wiki/International_Components_for_Unicode
Apple documentation
ATS and ATSUI starting point : http://developer.apple.com/documentation/Carbon/Conceptual/ATS_Concepts/atsfonts_intro/chapter_1_section_1.html Apple's starting page leading to deeper docs: http://developer.apple.com/documentation/TextFonts/Typography-date.html
New Font Management
[FIXME]
See Herbert's Duerr document : http://www.openoffice.org/files/documents/16/1603/vcl_new_fontmanagement.pdf
This work is part of http://wiki.services.openoffice.org/wiki/Mac_OS_X_Porting_-_Work_Areas/Todo%27s
( Ericb 14:37, 21 May 2006 (CEST) )