I noticed when playing with SourceSansVariable-Roman.ttf and SourceSansVariable-Italic.ttf in Samsa (Version 3.006 for both fonts) that, in some glyphs, two of the phantom points have unexpected movement through the variation range of the wght axis.
To replicate the issue, go to Samsa, load Source Sans, either Roman or Italic, then enable point numbers in the UI panel. Then select the D glyph using the Glyphs panel. Now move the wght axis slider from the minimum position to the maximum position. You will see two points 24 and 25 superimposed at at (0,0) at wght 200, then by wght 600 the points have moved together to (0,550), then by wght 900 then have moved back to (0,0). This movement serves no purpose that I can see.
These two points are the second pair of phantom points, and they represent the vertical equivalent of lsb and advance width.
The issue affects all Latin caps that have an intermediate master, i.e. D, H, M, N, O, T, W, Y. The issue may well affect many more glyphs.
I noticed when playing with SourceSansVariable-Roman.ttf and SourceSansVariable-Italic.ttf in Samsa (Version 3.006 for both fonts) that, in some glyphs, two of the phantom points have unexpected movement through the variation range of the
wghtaxis.To replicate the issue, go to Samsa, load Source Sans, either Roman or Italic, then enable point numbers in the UI panel. Then select the
Dglyph using the Glyphs panel. Now move thewghtaxis slider from the minimum position to the maximum position. You will see two points 24 and 25 superimposed at at (0,0) atwght200, then bywght600 the points have moved together to (0,550), then bywght900 then have moved back to (0,0). This movement serves no purpose that I can see.These two points are the second pair of phantom points, and they represent the vertical equivalent of lsb and advance width.
The issue affects all Latin caps that have an intermediate master, i.e.
D,H,M,N,O,T,W,Y. The issue may well affect many more glyphs.