question about assigning shaders and ID mattes

# 1 05-05-2012 , 08:54 PM

Compositor, Double Negative , London
Join Date: May 2012

Location: London

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question about assigning shaders and ID mattes

hi, so i want to start rendering out some ID mattes for different parts of this UFO i made, i want to be able to make RGB mattes for each panel and ideally bits like the bevelled corner edges . the model was made out of a torus shape to begin with then tweaked to have 12 divisions and finally some bevelled edges and grooves were added along with the bolts and dome etc.

can i assign say a red green or blue shader using face selection to one of the panels ive highlighted in the pic? i cant seem to do it. if i cant do it this way whats the best way to do it? i really dont want to have to roto this in nuke!

thanks
j

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# 2 05-05-2012 , 10:22 PM

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Not sure how you would specifically render out a material id (such as recognised by fusion), but you could select faces, right click, assign material, and choose "surface shader". If you render these in a seperate pass you will have flat colours per surface shader assignment. So for example you could assign a red surface shader, then use that pass as a mask in your compositing map (selecting red as the mask channel).

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# 3 05-05-2012 , 11:55 PM

Compositor, Double Negative , London
Join Date: May 2012

Location: London

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thanks!

yeah thats what i meant i just need to be able to assign red green and blue shaders to specific faces so i can re-order the channels in nuke . thanks ill give it a go! first time using maya!

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# 4 06-05-2012 , 12:01 AM

Compositor, Double Negative , London
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nope!

nah its not working, i select the fce i want - right click - assign new material - surface shader which i made red and it makes the whole torus object red and not the specific face. not sure if thats what you meant ? i only want to shade the specific face i am selecting. i dont want to have to chop up the entire model into seperate components itll take me hours!

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# 5 06-05-2012 , 12:11 AM

Compositor, Double Negative , London
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think ive fixed it

i think ive done it, you select the face, send it to UV's then add the material, that seems to work . id be greatful if anyone can tell me if theres a better way or if im doing this correctly though

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# 6 06-05-2012 , 04:41 AM

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You can create a simple shader like a lambert or a blinn and then select faces and assign that shader to those faces. You can do that for any faces you wish.

To make life easier down the road, I'd make a quick selection set under create for groups of faces.

"If I have seen further it is by standing on the shoulders of giants." Sir Isaac Newton, 1675

Last edited by ctbram; 06-05-2012 at 08:50 PM.

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# 7 06-05-2012 , 11:04 AM

The Nurb Herd
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if you want IDs you should use a surface shader as this will be a matte. create one of those, change the colour and assign it to the faces you want.

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# 8 06-05-2012 , 01:08 PM

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nah its not working, i select the fce i want - right click - assign new material - surface shader which i made red and it makes the whole torus object red and not the specific face. not sure if thats what you meant ? i only want to shade the specific face i am selecting. i dont want to have to chop up the entire model into seperate components itll take me hours!

Originally Posted by jamesamcpherson

Not sure why it's not working. If you are selecting faces, right clicking and then assigning a material, it should only be assigned to those faces. At least it works for me.

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# 9 06-05-2012 , 04:26 PM

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What is an ID matte and what is the difference of using a surface shader with an assigned color and a lambert with color? I don't do compositing so I am assuming this ID Matte term has something to do with that since a quick google turned up a bunch of after effects hits.

I am guessing it is for selecting parts of an image by color for masking and such inside AE or similar app? And I am guessing the difference between a lambert and a "matte" is the matte is not affected by lighting.

Applying a surface shade and setting out color on a per face basis works fine for me so not sure where it's failing for you.

The top red ring is a group of faces, the blue and yellow are single faces, and the bottom red loop of faces is a red lambert attached. So I can see the reason for a colored SS verses a material like a lambert now.

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"If I have seen further it is by standing on the shoulders of giants." Sir Isaac Newton, 1675

Last edited by ctbram; 06-05-2012 at 04:38 PM.

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# 10 06-05-2012 , 07:28 PM

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Create selection sets too to help you assign without having to keep selecting each face everytime you want to do a different pass

J

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# 11 06-05-2012 , 08:25 PM

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hi , try to create ''selection sets" by the the it will be better to work easy and quickly ..

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# 12 06-05-2012 , 10:53 PM

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didnt I just say that???

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# 13 06-05-2012 , 10:56 PM

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Yup, and ctbram said it about 5 posts up too. At least the op won't forget user added image

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# 14 06-05-2012 , 11:17 PM

Lead Modeler - Framestore
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hahaahhhhhhhaaaaaaaaaaaaaaaaaaaaaaaaa awsome!! I totally missed that tbh. I was trying to read everything too being said....no excuses though!! feel free to beard slap me!

https://3.bp.blogspot.com/-ims_lcZK5b...d-slap-gif.gif

Jay

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