Arbitrary glyphs in post-processor
Think about allowing arbitrary glyphs to represent data (like our 3D arrows).
Definition: Glyph = drawable rigid object with a single associated scalar/vector or tensor value.
A glyph could be loaded as a mesh or a geometry; create vertex array or display list for each; select glyph in Point/Vector/Tensor display dialog; define number of values to transform glyph (quaternion + scale{x,y,z}?).
Cf. old implementation for LMGC