Meir TOLEDANO wrote: > 1. How, the browser validate a font? For example if the font have > glyph codes in CC (control character), the font seems to be found > invalid by Firefox. Another example, some malformed fonts has > "unvisible" glyph (glyph with no contour but with width), how the > render engine deals with. What is the exact rule? Which class in the > source code is responsible of validation, where it is?
On Windows/OSX/Android our font-matching code explicitly treats some control code ranges as "not available" so that we don't spend time searching for a font for them. > 2. What is the font rendering engine? Is it FreeType? Which version? If you're thinking about the code used to rasterize glyphs, we use platform libraries, so FreeType on Linux, GDI/DirectWrite on Windows and CoreGraphics on OSX. > 3. Which font format is supported? Which one is recommended if any? > Same question for mobile version of Firefox. For downloadable fonts, WOFF is recommended but either TrueType or OpenType CFF fonts will work just fine. > 4. What about Kerning and Ligature in Firefox? Are they supported? > Mobile version? See for yourself! Kerning and ligatures have been enabled by default since Firefox 3. > 5. About font fallbacking, CSS norm seems to recommend panose-1 > classification. Is this features supported? Not sure what you looking at, the old 1998 CSS2 spec? If a suitable font is not found for a given character in the font family list, then appropriate pref fonts are considered first (based on the coderange of the character), otherwise all fonts on the system are searched. > 6. Which font table (GDEF, FFTM...) is supported? OpenType layout tables are supported, otherwise exact table support varies by platform. Keep in mind two things: (1) glyphs are always drawn using platform libraries and (2) there is a sanitizer (same as Chrome) that validates fonts before they are used. Cheers, John Daggett Mozilla Japan _______________________________________________ dev-tech-layout mailing list [email protected] https://lists.mozilla.org/listinfo/dev-tech-layout
