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View Full Version : Blackhole shader for C4d?


gmask
08-26-2005, 06:41 PM
A co-worker has asked me if there is a "blackhole" shader for c4d. Thatis a shader that will subject from the alpha of any objects iintersecting with it. In Maya all shaders have a alpha level settings and in some programs this is called a background shader.

eldonaldo
08-27-2005, 10:46 AM
nothing like that in cinema afaik.. would be great though..
everything you can do is rendering your matte seperately by using black and white materials..

lllab
09-21-2005, 12:08 AM
sounds interesting, what does it precisely with the alpha?
is the like an alpha mask for materials?

cheers
stefan

Per-Anders
09-21-2005, 12:25 AM
um, i'm afraid i really don't understand what's being asked for. maybe an example of what it is he wants would be a good way to clarify matters?

JoelOtron
09-21-2005, 02:52 AM
Sounds like the proximal shader to me (?)

Activate it in your alpha channel then drag the objectyou want to intersect with--and the alpha will activate upon interstcion with that object.

Strata Studio (going back almost a decade) had an "antimatter" function--sort of a boolean post effect. Is that what your getting at?

wurp
09-22-2005, 10:52 AM
a black-hole shader is something you use when rendering in multiple layers when having objects that overlap. What you do is assign a shader that renders black in both rgb and the alpha channel to all the objects you want to exclude from that pass, this way you can basically render each object in the scene as a separate pass and then colorcorrect each one in post later on, the bonus side of using a black-hole shader is that the objects still cast shadows and so on, so the render looks the same, one problem is ofcourse when you have secondary rays in the scene, reflections and such, in that case you need to also render out the reflections etc as a separate pass..

I dont use c4d so I dont know exactly how to set this up, but it should be quite simple as its a common method to use.

interactiveBoy
09-22-2005, 02:08 PM
we have something far more powerful - object buffers.

Creature
09-22-2005, 02:19 PM
Yes, object buffers are the solution to this.

Asign an object buffer ID to any object you want on a seprate layer. You do this by giving those objects a render tag. Inside the render tag you'll find the object buffer settings.

Then in Render Settings (Crtl-B) you activate Multipassrendering and add all Object Buffer IDs as seperate Layers.

Done

ThirdEye
09-22-2005, 02:21 PM
Yes, object buffers are the solution to this.

Asign an object buffer ID to any object you want on a seprate layer. You do this by giving those objects a render tag. Inside the render tag you'll find the object buffer settings.

Then in Render Settings (Crtl-B) you activate Multipassrendering and add all Object Buffer IDs as seperate Layers.

Done

the render tag's called Compositing Tag now

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09-22-2005, 02:21 PM
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