Re: [ft-devel] Having trouble rendering emojis with FreeType (Re: Freetype-devel Digest, Vol 172, Issue 22)

[Hin-Tak Leung]

Hi,

Sorry for coming into this thread a bit late. You basically found out something 
that's fairly well-known (at least for many of the font people) about emoji 
fonts, or bitmap fonts in general. Most Emoji fonts internally store the glyph 
shapes as colour bitmaps - png, sbix, etc, so they are fixed resolution. The 
only known exception AFAIK at the moment are a few emoji fonts from 
Mozilla/Adobe camp, which stores them as SVG's. As general bitmap fonts go, 
obviously trying to load them at a size not at one of the designed size, would 
fail with an "invalid pixel size" error.

I added some code to skip "invalid pixel size" in FontVal a while ago, because, 
as I explained above, it is not a fatal error, and quite expected for certain 
kind of fonts, and therefore does not indicate a flaw in the font.

The list of designed sizes are listed at the bottom of a "ftdump <font>", so 
you can get at them. There is also a Emoji font display example in freetype-py 
. You might find it quicker to use the freetype python binding than with 
compiled code for certain tasks or explorations.

HTH.