Right now the glyph atlas pipeline computes the UVs for glyph sampling in the fragment shader. This is probably much more expensive than needed, we should make this shader look more like the Skia shader.

I experimented with pulling the geometry computations into the text contents and it did significantly improve performance. There is probably more low hanging fruit here if we work at it a bit.

From the editorial page of wonderous with lots of text

Before

After