I think the issue with fast/text/emoji-web-font.html (FruityGirl) is that DirectWrite now "supports" CBDT/CBLC fonts. Before this font would have simply failed to load with DirectWrite, but now it will load. However, Skia doesn't currently support the particular call to extract the glyph rendering. Essentially, DirectWrite now understands this font, but it doesn't really know how to render these glyphs. There's a way to request the raw png data out so that it can be rendered, and Skia needs to add support for that call.

Thanks for taking a look. Either we'd add support for it through Skia, or - and I will be working on that, adding cross-platform CBDT/CBLC and sbix support through deferring to SkFontMgr_empty/FreeType-backend.

Skia now supports PNG based fonts like sbix and CBDT/CBLC with DirectWrite when the DirectWrite is new enough to support the font format. In particular fast/text/emoji-web-font.html now works as expected (with color asterisk) on my Windows 10 1709 box.

Ben, do you have a bug/CL reference for the Skia fix? Is this really fixed through the Skia fixed or through the cross platform bitmap fonts fix in  issue 758209 ?

If Skia supports this for DWrite for a web font now, we should have a version check and take the FreeType path for CBDT/CBLC on older versions. 

Also, it's good to see Skia support for CBDT/CBLC through DirectWrite is there, since this is essential for system fonts of that type.

Reopening to put a version check and DWrite/FreeType fork in place.

The Skia change is https://skia-review.googlesource.com/c/skia/+/141427 . Note that there is one known bug in there that we're planning on fixing today. I think the selection of backend for webfonts can just be done by trying to load the font with the DirectWrite SkFontMgr and seeing if it comes back nullptr or not. If the format is recognized everything should just work.