I just installed beta 34 and started by trying the new translucency example, but
it runs so slow, so, is every effect necessary to see that isolated feature or
what can I rip off from the file?

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Mr schrieb:
> I just installed beta 34 and started by trying the new translucency example, but
> it runs so slow, so, is every effect necessary to see that isolated feature or
> what can I rip off from the file?

Disabling photons should speed it up. You can also try reducing the 
radiosity quality settings.

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clipka <ano### [at] anonymousorg> wrote:
> Mr schrieb:
> > I just installed beta 34 and started by trying the new translucency example, but
> > it runs so slow, so, is every effect necessary to see that isolated feature or
> > what can I rip off from the file?
>
> Disabling photons should speed it up. You can also try reducing the
> radiosity quality settings.

Thanks, I just hadn't well read your syntax tip so now that I have I tried a
minimal scene. It works fine and renders fast. I have one question:
For realistic results is the sum of the front and back diffuse value + specular+
ambient supposed to stay below one, or just the two diffuse values can go up to
one besides the rest of the ordinary values?

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> I just installed beta 34 and started by trying the new translucency example, but
> it runs so slow, so, is every effect necessary to see that isolated feature or
> what can I rip off from the file?
> 
> 
If you disable the photons, you'll see that it's MUCH faster. Only 
looking at the radiosity pretrace, it's around 10 times faster without 
photons than with.


Alain

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> clipka <ano### [at] anonymousorg> wrote:
>> Mr schrieb:
>>> I just installed beta 34 and started by trying the new translucency example, but
>>> it runs so slow, so, is every effect necessary to see that isolated feature or
>>> what can I rip off from the file?
>> Disabling photons should speed it up. You can also try reducing the
>> radiosity quality settings.
> 
> Thanks, I just hadn't well read your syntax tip so now that I have I tried a
> minimal scene. It works fine and renders fast. I have one question:
> For realistic results is the sum of the front and back diffuse value + specular+
> ambient supposed to stay below one, or just the two diffuse values can go up to
> one besides the rest of the ordinary values?
> 
> 

The front plus back values sum should be less or equal than one. Also, 
as before, the total diffuse plus the ambient should add to one or less.
BUT, there is nothing preventing you from having diffuse 1,1 if you want to.

The specular/phong hilights can give a total larger than one when 
combined with the oter parameters.



Alain

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Alain schrieb:
> The front plus back values sum should be less or equal than one. Also, 
> as before, the total diffuse plus the ambient should add to one or less.
> BUT, there is nothing preventing you from having diffuse 1,1 if you want 
> to.
> 
> The specular/phong hilights can give a total larger than one when 
> combined with the oter parameters.

I /think/ you're wrong, theoretically:

- Light reflected in a rather directed fashion is unavailable for 
diffuse reflection, and therefore the diffuse term(s) [1] should be 
reduced accordingly when using specular or phong highlights.

- Ambient, on the other hand, is used not to model what happens with 
incoming light, but how much incoming light there is in the first place, 
by specifying an "input" term to add to whatever comes from regular 
light sources. The idea is to model light scattered diffusely from other 
objects onto this one, and should therefore be proportional(!) to 
other(!) nearby objects' diffuse term. (Unless ambient is used to model 
glowing objects of course.)

[1] As for backside vs. frontside diffuse term, it should be noted that 
light making it though to the other side of the object is unavailable 
for diffuse reflection on this side.

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clipka <ano### [at] anonymousorg> wrote:

> [1] As for backside vs. frontside diffuse term, it should be noted that
> light making it though to the other side of the object is unavailable
> for diffuse reflection on this side.

Does that mean that all the rest should add up to one and the back diffuse can
still go anywhere between 0 and 1 again? (sorry to ask again)
I know any values are allowed, I'm just asking for realistic limits

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Mr schrieb:
>> [1] As for backside vs. frontside diffuse term, it should be noted that
>> light making it though to the other side of the object is unavailable
>> for diffuse reflection on this side.
> 
> Does that mean that all the rest should add up to one and the back diffuse can
> still go anywhere between 0 and 1 again? (sorry to ask again)

No, sorry, that's a misunderstanding; what I meant to point out was that 
to get realistic results, when you increase back-side diffuse value (= 
more light gets through to the other side), you should decrease the 
front-side diffuse value accordingly (= less light stays on /this/ side).

Thus, you should make sure that:

   diffuse(front) + diffuse(back) + specular + phong  <=  1.0

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clipka <ano### [at] anonymousorg> wrote:
> Mr schrieb:
> >> [1] As for backside vs. frontside diffuse term, it should be noted that
> >> light making it though to the other side of the object is unavailable
> >> for diffuse reflection on this side.
> >
> > Does that mean that all the rest should add up to one and the back diffuse can
> > still go anywhere between 0 and 1 again? (sorry to ask again)
>
> No, sorry, that's a misunderstanding; what I meant to point out was that
> to get realistic results, when you increase back-side diffuse value (=
> more light gets through to the other side), you should decrease the
> front-side diffuse value accordingly (= less light stays on /this/ side).
>
> Thus, you should make sure that:
>
>    diffuse(front) + diffuse(back) + specular + phong  <=  1.0

Thanks. This way seemed more logical from the start but that's perfectly clear
now.

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