how to access Cd Attribute from alembic file to color a mesh light in mtoa

[danthompson616]

Hi there I've been trying to figure out how to access the Cd attribute from an alembic cache that was generated in houdini. my plan was to use aiUserData and pipe that into the lights color.

I'm aware that you can use alembic gpu cahce to get the attributes but a mesh light needs real maya geo so that seems like a dead end.

I'm also aware that you can use bifrost to wrangle that attributes from the alembic cache which is nice but again mesh lights cant recognise the bifrost shape node. There is a node that converts the bifrost shape to maya geo which is nice but it doesn't seem to bring the Cd attribute with it so this also seems like a dead end.

I would be grateful if someone could suggest and alternative solutions. This is something I have been doing for years rendering fx in htoa but it seems as though the same technique cant be replicated in mtoa.

Thanks in Advance!

Dan.

[Stephen.Blair]

You were doing it with HtoA? How?

[danthompson616]

Hi There,

Mesh lights in htoa have a parameter on the called 'shader' mesh lights in mtoa they do not. From the htoa mesh light docs...

Shader

Shows the Color Shader parameter with the path of a vopnet that is contained inside the mesh light for convenience.

A shader and images network can be added inside this vopnet and connected to the the color parameter of the Light Output.

Mesh lights have a parameter on the called 'shader' mesh lights in maya do not 4:03From the htoa mesh light docs...Shader
Shows the Color Shader parameter with the path of a vopnet that is contained inside the mesh light for convenience.
A shader and images network can be added inside this vopnet and connected to the the color parameter of the Light Output.

https://docs.arnoldrenderer.com/display/A5AFHUG/Mesh+Light

I was hoping to be able to do a similar thing with bifrost in maya but it doesn't seem to work 😞