[Devel] FTC_Manager_New num_sizes question

[Ken Hancock]

I had been going under the assumption that:

num_faces = 2
num_sizes = 2

Would mean that in my cache I could have Arial 14 & 18 point as well as
Times 14 & 18 point.  However, looking at FTC_SCALER_COMPARE it seems that
it checks the face_id as well as the size which means that I can only have
only two of the above 4 combinations.

Is this the original intention?  Is there a clearer way to document this?  A
default of 4 sizes in light of this seems a bit small...