Motivated by previous post on this group, i did some thinking on how top
implement motion-blur in POV-Ray most efficiently. I came to following
conclusions:

To be able to render motion blur, POV must do following things:

1. Have decent way of scripting motion-paths for object, it's
acceleration/deacceleration and rotations. Smoothest way should probably
be to use bezier curves for this. It would rule-out hand-writing scenes
with motion blur, but who cares. It's time to say goodbye to it anyway
(well, that's my opinion on that issue, don't flame  me for it, let's
concentrate on motion-blur)

2. POV-Ray should first be able to accuratly calculate bounding box that
surrounds blurred object at all positions on it's path. 

3. While rendering , every time that ray intersects this motion-blur
bounding box, object should be jittered across it's motion path in
time-domain and re-tested with same ray. This would give us oversampled
Monte-Carlo approximation of it's blurred trail. It will also work
satisfactory with shadows, reflections and such.

Altough this jitter-samling technique is time-consuming, it would be a
good way of doing motion-blur for small objects in a scene that is
stationary.

Of course, there will be a threshold when it's less time-consuming to
render multiple images and average them togheter instead, but that would
only apply to images with lot's of moving object or moving camera.

Please give me some useful input, like if this is feasible way to go
before i start experimenting.


Cheers, Goran

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