Hello!

While trying to make an animation out of some simulation results, I 
encountered a strange behaviour that makes the render time shoot up 
dramatically...

It seems that the bounding box optimization on some objects is turned on 
or off at the first frame only, and remains set for the subsequent 
frames. Example files:

// animbug.pov //////////////////////////////
camera{location 0 look_at x}
light_source{10000 color rgb 1}

#declare i = 0;
#while(i<clock)
     sphere{i*x - y, 0.1 pigment{rgb 1}}
     #declare i = i+1;
#end
////////////////////////////////////////////

;; animbug.ini ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
Input_File_Name = "animbug.pov"
Initial_Frame = 1
Final_Frame = 80
Initial_Clock = 1
Final_Clock = 80
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;

If the render is launched with the command:
$ povray animbug

it takes a long time and if you look at the output, bounding boxes are 
never used to speed-up intersection tests.

On the other hand:
$ povray animbug +MB1

renders faster and uses bounding boxes.

More generally it seems that if the number of objects on the first frame 
does not exceed the bounding threshold the optimization is never used, 
even if there are more objects in the rest of the frames.

Is this the expected behaviour? Am I the only one starting with just 1 
object in the first frame :-) ?

Regards,

-- 
Vincent

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