VRaySphereFade using Cylinder insted of Sphere?

Hi, I have a animated (camera and objects) scene with a steelwire that needs to be re-rendered because of a displacement error that made the wire to thick. This means that I need to render the steelwire plus a area on the sides of the wire because the existing wire is to thick (the red areas on the picture bellow) Is it possible to render only the red areas in the re-render?

Tested the VRaySphereFade, but that only use a sphere and to cover the wire from top to bottom it’s really not far from rendering the entire scene instead of only the steelwire areas. It would be nice to use the wire object to define the fade areas instead of a sphere. Any ideas?

Thanks from Chris

Hi,
reminds me of the idea someone had about an imagesequence that would drive the region to render. Would come handy in such cases. Writing a CylinderSphere would be another solution. Would be a good training for someone who wants to learn the VRay SDK…
Maybe add it to the wishlist?

Dieter

Maybe put two planes, one to each side of the wire by a couple of inches and give them a black material and uncheck visible to reflections, cast shadows and receive shadows and in the vray properties uncheck visible to GI. Should render the whole frame but go pretty quick over the black areas. Really just the first thing off the top of my head…

hmm… can try that… the camera is fly-trougt, so I think its going to tricky, but I will try :slight_smile:

But it would be nice to have some other shapes than just the sphere in the VraySphereFade plugin… :stuck_out_tongue:

What about making the VraySphereFade like a material you can put on objects? and then you could just select the fade-radius in the material… could be handy for many things…

thanks

Re-rendering is best, Here is something to think about though that might lead you to something that could work for you

You could render our a mask to mask out the incorrect part of the image.

1) create a cylinder that fully encompasses the bad wire (clone the wire, apply a push modifier to it, amount:6")
2) select EVERYTHING in the scene, right-click->Vray Properties and set the alpha contribution to -1.0.
3) select the cylinder with the push modifier and change it’s alpha contribution to 1.0
4) Set your Environment background image to 0,0,0 (jet black)
5) Render out your camera’s alpha only

this will give you the problem area mask which in after effects you can set to mask out that area.

Hope this technique helps in some way

Just a thought, but depending on how the wire is made, you can just put a whole bunch of spheres through it’s length…

Jorge