Viewport renderer update issues

[Horvátth Szabolcs]

Hi,

We're writing a viewport renderer and get strange viewport refresh
issues when objects are selected.
Is there any way to know what caused an update call? And is it possible
to distinguish camera or light dragging (continuous attribute change)
from attribute update, just as Maya can do lazy interactive shading
using bounding box or points for camera move and do a full update only
when its finsished)?

Cheers,
Szabolcs