On Sun, 15 Feb 2004 21:43:35 -0800, Darren <dne### [at] sanrrcom> wrote:

>> Yeah. I see now. It just took me a while to understand what I was doing 
>> wrong and why it would be slow. 
>
>Well, it seems to be much improved, altho not as fast as I'd like. (Is 
>it ever?)

No. As I can see from your scene file you want to use area lights
later :-)

>I've also upgraded to 3.5.
>
>With all the lights in place (Maybe 150 or 200 torches, each actually 
>being two light sources) it runs some hundred or two PPS with AA turned 
>on at +Q5. I'll be happy if I can keep it in the tripple digits, I think.

I've just traced Keep_33_37_0_sw.pov (640 x 480, AA=0.3).
It took 3 hours and 5 minutes.
Commenting out the lights it needed 6 seconds.
It's the number of light sources that slows down your scene.
For each visible surface point a ray is traced to each of the light
sources to see whether it contributes or is blocked (which is probably
almost always the case).
If your scene generator can put the 

>I tried taking the whole castle and setting it clipped_by and bounded_by 
>just one corner, and it didn't render anything outside the box, but it 
>didn't render noticably faster either, even tho I clipped out most of 
>the lights.

???
Clipping/bounding an object (the 'torch' union?) doesn't affect (hide)
the light sources that are defined inside of them.
What do you mean with 'clipped out most of the lights'?

>I don't notice any especially inefficient ray tests, either.

They are as efficient as possible :-)

>Are there other clues? Maybe some way of clipping out areas I know don't 
>affect the final scene without actually changing the building code on 
>the fly?  (I could use the macros to nuke out large chunks of the 
>building as appropriate, but I'd rather do it without having to 
>basically #ifdef out the rooms I'm not currently rendering with this 
>particular camera.)
>
>I know it's hard to answer such a thing without seeing source. (And I'm 
>happy to show people source if they care, but it's ugly, since it's 
>automatically generated.) But ... is there anything else I should be 
>looking at?  Are the lights going to spectacularly slow down rendering?

Yes.
 
>Maybe if I just comment out particular blocks of lights when I'm not 
>rendering near the camera?

If you can group the lights somehow (maybe room1, room2, ...)
this will probably help to selectively 'switch' them on and off which
will definitely speed up the rendering.
If your scene generator is able to do this you should have a look at
the new 'light_group' object.
It enables you to restrict the lighting of a light source to the
objects that are declared together with the light source.


-- 
Andreas

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