RenderMan & RISpec >> render passes

by tak_fail » Thu, 07 Apr 2005 15:48:28 GMT

I am going to do some photrealistic render of an architectual
building. I would like do know how many passes will give me the best
control for compositing.

from the rendermanacademy, they showed an example of a few passes
i.e. diffuse, specular, reflection, ambient, shadow
http://www.rendermanacademy.com/docs/ClassFrame01.php?sel=1

I will be using mtor.
my plan is to do
diffuse+ specular+ reflection+ ambient occlusion+ shadow+ irradiance+
caustic

do you think if it is good enough for architectual rendering? Please
feel free to give me more suggestions

RenderMan & RISpec >> render passes

by forkazoo » Fri, 08 Apr 2005 07:09:17 GMT


There isn't any hard and fast rule. I assume that others with more
experience can offer more wisdom than I. The biggest issue is how much
do you want to tweak? How many interesting steps are in your shader
that you will want to control?

For example, if you have a "wet brick" shader that darkens all the wet
parts and makes them more specular, you may want a "water channel" to
control how much the water darkens the diffuse reflection. Or, maybe a
channel that separates out the grout between the bricks so that you can
adjust the tint of the grout in post to show your clients how great it
would look as hot-pink. Maybe you have illumination coming from both
artificial lights and moonlight. You might make separate passes for
each light, so you can control how bright the moonlight appears.

So, yeah, making distinct passes for diffuse and spec. and reflection
is a great starting point, and certainly won't hurt, but without
knowing what you want to tweak in the scene, nobody would have any way
to say with certainty that you need channels for the normal, or
distance from the mothership.

RenderMan & RISpec >> render passes

by Atabet » Sat, 09 Apr 2005 03:33:33 GMT

Hi,

You should simply include a render pass for anything that you can't get
quite right within the render itself. Also include a pass for any
detail you want to experiment a lot with - like the color of the sky.

Matthew

RenderMan & RISpec >> render passes

by Atabet » Sat, 09 Apr 2005 03:34:17 GMT

Hi,

You should simply include a render pass for anything that you can't get
quite right within the render itself. Also include a pass for any
detail you want to experiment a lot with - like the color of the sky.

Matthew

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