Ambient occlusion tests

[Titus]

I'm working on a little project for public TV and wanted to test the new and free ambient occlusion shader (as seen on flay.com). I have familiarity with this technique since I'm a RenderMan user but never had time to develop this plug-in for LW before. This scene contains two lights only, the shader creates hard shadows but I like how the objects have volume.

[wacom]

Are you using the same one I'm using (SG_AmbOcc_Exp.p)? You can get VERY soft shadows with this one- and you have control over how hard or soft they are, and the spread of the shadows.

Here is an example of just what the shadder has done with the diffuse channel- no lights...

[wacom]

Here is another- with the map applied and two area lights this renders out in 28sec in Fprime on my 1.8Ghz machine...

nothing impressive...but it's nice to not have to use Radiosity to get that "look" everytime.

[Hervé]

cool... but I thought shaders would not work with F_Prime...? :confused:

[UnCommonGrafx]

Ya, S'plain that, wacom...

Ahh, you baked it out, huh?

[antwik-2]

Ya i also tried that occlusion shader, its nice
but the render times dont get that much faster with it instead of radiosity in fprime.
so why use it?

[UnCommonGrafx]

SHADERS!!!!!!!!!!

Gosh, for the first few months of FPrime, I gave up F9. Recently, I've gone back to using the native renderer with all of the shaders I've been neglecting and FPrime is now just a glorified texturing window.
Not using shaders really cuts down on the usefullness of FPrime, for me. And I've got LOTS of shaders to use that have gone by the wayside.

[ingo]

Ya i also tried that occlusion shader, its nice
but the render times dont get that much faster with it instead of radiosity in fprime.
so why use it?

The ambient occlusion shader has nothing to do with raydiosity, so its not an replacement. Instead you can use it as an addition so you can use a faster raydiosity setting. Thats what i'm doing with ShadowDesigner, which generates a similar effect.

[Musart]

Here is another- with the map applied and two area lights this renders out in 28sec in Fprime on my 1.8Ghz machine...

nothing impressive...but it's nice to not have to use Radiosity to get that "look" everytime.

Hi,

I wonder how did you get the plugin works with Fprime ???

Thanks

[wacom]

Sometimes the shader is slower than Fprime...and sometimes it's faster. What I like is to either bake it out (if I'm doing a lot of animation and the camera moves quite a bit) or do a shader only render and then apply that to my diffuse channel via front projection.

The advantages to this are when you want to use area lights in FPrime with Inverse distance or inverse distance squared and rendertimes due to "super sparkels and black death dots). FPrime is so fast with area lights in plain raytraced mode that it's worth the work around at times. Often you'll find that you can turn off almost all of your lights shadows when you've applied this shadder, but that depends on the scene and it's lighting...

I wouldn't say it works for everything, but it can be something to turn to when you're having problems with FPrime in radiosity modes. I look at it as my Fprime fake radiosity setup helper...

For those who don't have Fprime but want a GI look to animation I've read that you can set this plug-in to say 8-6 rays and up the AA to get some fairly good/fast GI going.

Like I said...just like everything else it isn't a cure all tool, but one that can and should be tried and then added to your tool box. I hope we can all agree that it's a 100 times better than the older Ambi-Occu shader...