Solves long-standing issue when dependencies of disabled modifiers are
evaluated.
Simple test case: no drivers or animation. Manually enabling modifier
is expected to bring FPS up, enabling modifier will bring FPS (sine
evaluation can not be avoided)
F13336690
More complex test case: modifier visibility is driven by an animated
property. In am ideal world FPS during property being zero is fast
and when property is 1 the FPS is low.
F13336691.
Differential Revision: https://developer.blender.org/D15625
The issue was caused by the fact that objects with driven or animated
visibility were considered visible by the dependency graph evaluation.
This change makes it so the dependency graph evaluation is aware of
visibility which might be changing. This is achieved by evaluating the
path of the graph which affects objects visibility and adjusts to it
before evaluating the rest of the graph.
There is some time penalty to this, but there does not seem to be a
way to fully avoid this penalty.
With the production shot from the heist project the FPS drops by a
tenth of a frame (~9.4 vs ~9.3 fps) when adding a driver to an object
which keeps it visible. Note that this is a bit hard to measure since
the FPS fluctuates quite a bit throughout the playback. On the other
hand, having a driver on a visibility of a heavy object from character
and setting visibility to false gives big speedup.
Also worth noting that there is no penalty at all when there are no
animated visibilities in the scene.
Differential Revision: https://developer.blender.org/D15498
