prman motion blur and other simple questions

[bareja]

Hi I have problem with motion blur in renderman, I've created scene where i have two animated objects:

The left sphere has animated parameter /obj/geo1/tx, right sphere has animated transform SOP (ex. /obj/geo2/transform1/tx). And when object is deformed in SOP level i can't set up motion blur. What should i do to enable motion blur on deformed objects. Which attribute should i add to geometry to enable motion blur on deformation ?

i think i've added all motion blur attributes, but without any resoult:

allowmotionblur
geo_motionsamples
motionstyle
ri_shutterclampmotion
ri_tracemotion
rib_motion01
rib_motionoffset
rib_motionscale
ri_motionfactor
ptmotionblur
ri_extrememotiondof
ri_samplemotion

And in /out/rib1 allow motion blur parameter is on.

Please Help.

Edited May 27, 2009 by bareja

[stevenong]

It's been a while since I've used prman but try increasing the Geo Time Samples on the Renderman ROP to 2 for deformation blur.

Cheers!

steven

[bareja]

Hi thanks a lot! Everything works

Cheers

[bareja]

OK, motion blur works but now i have another problem, i'm reading article about 'Point-Based Approximate Ambient Occlusion', and now i should declare display channel: DisplayChannel "float _area", it is possible to do that ? I wanna use bake3d() rsl function. I've found attribute called Display Channels, but it's only for geometry. It is possible to add global ri instructions to my scene ?

Please help.

[bareja]

ok works i just add AOV

[bareja]

Hey, another question about Point-Based Approximate Ambient Occlusion, I have strange resoults:

When cube is Polygonal geometry:

and when it's nurbs surface:

But there are still white edges on cube, anyone knows why i have white that wite edges ? I think it's problem with normals

scene with extruded ground polygonal grid:

Please help.

Edited May 28, 2009 by bareja

[brianburke]

Hey, another question about Point-Based Approximate Ambient Occlusion, I have strange resoults:

When cube is Polygonal geometry:

and when it's nurbs surface:

But there are still white edges on cube, anyone knows why i have white that wite edges ? I think it's problem with normals

scene with extruded ground polygonal grid:

Please help.

Hi bareja. The quality of the approximation is based laregely on the density of the pointcloud you feed in, so you might want to dial down the shading rate of your bake pass (or increase the resolution maybe). Also, decreasing the maxsolidangle in your occlusion call will help as well. If this doesn't clear that up, you can try toggling the sidedness of your occlusion call from "both" to "front" which will ignore backfaces when making the approximation.

Good luck dude.

Edited May 28, 2009 by brianburke

[bareja]

Hi thank you for really helpful advices.

cheers.