[Dev-luatex] Slowdown of font loading

[Patrick Gundlach]

Hi,

switching from LuaTeX 0.72 to 0.79.1 I experience a dramatic slowdown when reading fonts. I have not gone into details yet. 

I load texgyre heros (otf) in several instances and my former minimum document compiles in less than 0.5 seconds, now it's up to 2 seconds.

I have removed fontloader.to_table() and access the font structure directly, but this didn't change anything.

It looks as if the main computation time is in glyph.boundingbox. Is there any way to speed up the bounding box calculation?

Patrick