supress material assignment in mentalray

[mattd]

I am writing out a mi sequence for use as an assembly file in Maya. It works well, except that I have to prune out the material assignment so that the material can be overridden in maya. For now, i am using a text editor to search and replace the assignment with a blank space

material ["/obj/particle_emitter1-mat"] <--- have to remove this line from the mi file

it would be great if I could just get houdini to not assign the shader at all, is there some way of overriding the instance section with custom text within the ROP?

MD

[SpencerL]

I am writing out a mi sequence for use as an assembly file in Maya. It works well, except that I have to prune out the material assignment so that the material can be overridden in maya. For now, i am using a text editor to search and replace the assignment with a blank space

material ["/obj/particle_emitter1-mat"] <--- have to remove this line from the mi file

it would be great if I could just get houdini to not assign the shader at all, is there some way of overriding the instance section with custom text within the ROP?

MD

How are you accessing your houdini created .mi files in Maya? We bring in an obj written from Houdini into Maya and assign a Rendering Editors > Custom Text Editor. You need to make sure the .obj you bring in from Houdini is named the same as the name its listed as in the .mi file. When Houdini generates the .mi file it renames your object that you are writting out to something different. For example I am writing out geo1 object in my mi file. When I open the .mi file its renamed the object to this:

object "/obj/geo1-geo-base-0-geo"	# {

Which would mean that our object in Maya would need to be renamed to "geo1-geo-base-0-geo". We have a script which goes through the mi file and renames it back to geo1. After doing this, we assign our shader in Maya and it just takes that shader and ignores the one assigned in houdini.

[mattd]

I am using the new mi assembly in 2009(or render proxy as they confusingly call it here and there). The mi file is referenced under the mesh shape node of a standin object in mental ray->Render Proxy. If I understand what you are doing correctly, you are doing this manually by swapping out the mi reference after maya creates it's mi file. I am not using standalone, so I cannot try it.

This is by far the best solution I have found, since you never have to see the actual geometry from houdini in the maya interface (or you can load a non rendering stand in fbx), therefore maya can deal with it. It is my new fluids workflow and now I can totally replace realflow (rejoice!)

Also, thanks for your help on the other thread, the motion blur works great.

MD

How are you accessing your houdini created .mi files in Maya? We bring in an obj written from Houdini into Maya and assign a Rendering Editors > Custom Text Editor. You need to make sure the .obj you bring in from Houdini is named the same as the name its listed as in the .mi file. When Houdini generates the .mi file it renames your object that you are writting out to something different. For example I am writing out geo1 object in my mi file. When I open the .mi file its renamed the object to this:

object "/obj/geo1-geo-base-0-geo"	# {

Which would mean that our object in Maya would need to be renamed to "geo1-geo-base-0-geo". We have a script which goes through the mi file and renames it back to geo1. After doing this, we assign our shader in Maya and it just takes that shader and ignores the one assigned in houdini.

[SpencerL]

Ah, we use standalone and we change the houdini generated .mi file. Glad the motion blur is working for you.