dvmmul -- don't use entry [3] of a 3-component point!
for performance etc. tests.
And, in partiview version, make sure to *use* o2d/d2o if provided!
structure names (?!).
Default change: no longer skip blank times! Per-data time ranges now extend overall clock range, don't replace it. Reset material properties (shininess, specular, ambient) when drawing a lighted mesh.
