Random Material ID Colour

[ahmed_fawaz]

Hi,

Im a long term user but with Vray for 3ds max. I use this script http://www.scriptspot.com/3ds-max/sc...re-color-tools to assign wirecolours by material.
My new job requires me to use Maya. I am struggling to figure out how to get this workflow back.

So far my understanding is maya doesnt have wirecolour render element so this wont work but it does have material id. Issue i have is setting this up one by one is extremely time consuming.

Is there a script or a way to script it so i can select one object (i.e. a car) and the script will add a vray material id attribute to each part + use a random colour for each material.

Any help is greatly appreciated.
Thanks
p.s. i have looked high and low for this and have tried to make it myself but have failed. So now im reaching out to the pros!

[SonyBoy]

It's a hack, but if I'm understanding you correctly you could use the cryptomatte render element to do this. I'm assuming you need it in an RGB channel but it should be a simple enough case of shuffling that out in Nuke or After Effects.

[ahmed_fawaz]

Oh wow i haven't come across that render pass before. Just watched a tutorial on it on youtube and although its not 100% the same as what i wanted, i think its very useful!. Think this may do the job. Thank you SonyBoy I'll be testing it out on some scenes to see how i get on with that workflow

**Edit

After testing, i straight away realised theres an option for ID TYPE = Material name! Exactly what i wanted.

[SonyBoy]

Yep, there's three types, node name, hierarchy and material. You can even add multiple cryptomatte elements if you have use for more than one type. The only possible limitation is you have no control over the colors that are output but they can of course be edited in post if needed.

[ahmed_fawaz]

Im alright with that though. I just really wanted the materials to be grouped as single colours and this is great for it! I do have one issue though and im this must be a maya thing as ive never had this issue in 3ds max. When i save the exr with all the channels. My image is really dark and doesnt look like my beauty render. Any ideas?

**Edit
wow one of those days......ok so the render saves out fine! i didnt realise it was spitting out an RGBA pass which looks completely dark but the beauty render is in there.

Again thanks for all your help