I have build the following scene and I have trouble with the lightning setup.
I'm using an environment light with the ambient occlusion rendering mode and checked the irradiance caching on the mantra output node. I also have placed a sphere with a clay surface node to have something in the background and have shadow masked it for the evironment light. So far so good. I tried different settings but I allways get the speckles and can't get rid of that.
I also have setup a pbr a version which looks quit nice but takes very long to render. I think the settings which I have used have to be tweaked to get faster results but would be cool to have been both versions optimized.
I have provided both scene files.
lightning setup
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- roughsporty
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- circusmonkey
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Hi ,
See attached for a basic AO scene using your geometry. As you can see it renders very quickly with no artifacts. I could not do much with your scene as its all over the place in terms of correct work flow to get a good end result.
Note :- The env light sample value. Just like Mental Ray or renderman is uses values of 64 , 128 , 256 etc. Also I multiplied the colour value up to get your traditional AO pass. I also did some adjustments to the column which had no normals.
Another good pointer would be if you want to use DOPs you should be writing out all your geometry to disk beforehand. It will be much faster to simulate.
rob
See attached for a basic AO scene using your geometry. As you can see it renders very quickly with no artifacts. I could not do much with your scene as its all over the place in terms of correct work flow to get a good end result.
Note :- The env light sample value. Just like Mental Ray or renderman is uses values of 64 , 128 , 256 etc. Also I multiplied the colour value up to get your traditional AO pass. I also did some adjustments to the column which had no normals.
Another good pointer would be if you want to use DOPs you should be writing out all your geometry to disk beforehand. It will be much faster to simulate.
rob
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- roughsporty
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- circusmonkey
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Hi ,
No problems. Labeling stuff sure helps ! What are you going to do next with the scene ! Mega destruction ?.
Some tips to consider :-
Do you need all your columns to be destroyed ? If not consider just adding the geometry that needs to be to the RBD simulation.
Write out the geometry data and read from disk , so all those nodes dont need to cook before hand. The same applies to the simulation.
Deep shadow maps are really nice to use as again you write them to disk and then just read them back in. You can turn off their auto generation in the mantra ROP. Once you have written the maps out.
There's a distance value on the env light when set to AO , try to use it. Makes the AO calculation more efficient.
Rob
No problems. Labeling stuff sure helps ! What are you going to do next with the scene ! Mega destruction ?.
Some tips to consider :-
Do you need all your columns to be destroyed ? If not consider just adding the geometry that needs to be to the RBD simulation.
Write out the geometry data and read from disk , so all those nodes dont need to cook before hand. The same applies to the simulation.
Deep shadow maps are really nice to use as again you write them to disk and then just read them back in. You can turn off their auto generation in the mantra ROP. Once you have written the maps out.
There's a distance value on the env light when set to AO , try to use it. Makes the AO calculation more efficient.
Rob
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- roughsporty
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- circusmonkey
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Hi,
I did some cleaning of the scene and put in the settings which you have provided.
It looks much better now but a lot of grain everywhere.
Have you thought, looked up how occlusion works. What else about your model will cause problems, especially with the platforms you have created. Id be asking myself how come some of the pillars look great , others not so great and the platforms why are they so bad.
rob
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- roughsporty
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Hi Rob,
I followed up your tips and now I have a fairly good result with the settings in my environment light. I have used 128 samples, quit high and ends up with a huge rendering time but 64 samples wheren't enough.
I looked through the houdini help file concerning the usage of environment lights as Ambient Occlusion and they mentioned to use irradiance caching in the mantra node which optimize the rendering speed.
The rendering speed is optimized but there are blotches all over the place. The sample pic uses max spacing of 20 but even if I use 5 or 3 I'm ending up with tiny little blotches and also the rendering time goes up.
So I don't really see the advantage of using the irradiance cache or did I miss something?
I followed up your tips and now I have a fairly good result with the settings in my environment light. I have used 128 samples, quit high and ends up with a huge rendering time but 64 samples wheren't enough.
I looked through the houdini help file concerning the usage of environment lights as Ambient Occlusion and they mentioned to use irradiance caching in the mantra node which optimize the rendering speed.
The rendering speed is optimized but there are blotches all over the place. The sample pic uses max spacing of 20 but even if I use 5 or 3 I'm ending up with tiny little blotches and also the rendering time goes up.
So I don't really see the advantage of using the irradiance cache or did I miss something?
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- circusmonkey
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- roughsporty
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Ok, I have understand your point of scaling and if I scale my scene down I get faster results and can use less samples. To test this I have scaled down my entire scene 50 % and also I have added more detail to my geometry but the rendering time doesn't changed.
So, if I avoid the irradiance caching for what is it good for? I mean i have read about it in the help files and for me it makes no sense to use it because of the splotches in the images.
So, if I avoid the irradiance caching for what is it good for? I mean i have read about it in the help files and for me it makes no sense to use it because of the splotches in the images.
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- circusmonkey
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- roughsporty
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Thank you for your provided scene. I have looked to it and it worked but it's not a smooth clean render out. So as is in my scene.
I have made couple of changes to my scene and tweaked the settings, which I'm aware of.
Im' ending up with a setting of 64 samples in the environment light and the propper irradiance caching settings. I'm not happy with the quality and I ran in frustration cause the only way to avoid that is to increase the the samples to 128 or maybe 256 which dramatically will rise up the render times.
I really know thats houdini learning curve is not the easiest and maybe I missing some points but in other packages, which I'm using is this task, to render out AO in a reseanoable time, a fun part.
grmph, I want to smash the whole thing LOL
I have made couple of changes to my scene and tweaked the settings, which I'm aware of.
Im' ending up with a setting of 64 samples in the environment light and the propper irradiance caching settings. I'm not happy with the quality and I ran in frustration cause the only way to avoid that is to increase the the samples to 128 or maybe 256 which dramatically will rise up the render times.
I really know thats houdini learning curve is not the easiest and maybe I missing some points but in other packages, which I'm using is this task, to render out AO in a reseanoable time, a fun part.
grmph, I want to smash the whole thing LOL
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- circusmonkey
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Ahh that old frustration problem. There is no reason why you could not make a small scene with basic 3d objects and use that as a test bed for ideas and settings. Then it might be easier to point problems out that you are having.
What are you trying to show with your last image ? . It looks as expected.
Rob
What are you trying to show with your last image ? . It looks as expected.
Rob
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- roughsporty
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hehe, not so bad as it sounds in my previous mail. I definetly like tweaking cause you can so much learn about it.
The image looks good but it is grainy, maybe from the irradiance or from the 64 samples which I have to raise up. In theory there is no problem to use 128 or even 256 samples in the light but if I'm using it combined with the irradiance caching you have to use very small sample spacing and then you have nearly the same rendering times as without irradiance caching.
The image looks good but it is grainy, maybe from the irradiance or from the 64 samples which I have to raise up. In theory there is no problem to use 128 or even 256 samples in the light but if I'm using it combined with the irradiance caching you have to use very small sample spacing and then you have nearly the same rendering times as without irradiance caching.
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