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Is there any way to make a totally white shadeless material in Blender Cycles? I need to render something as a silhouette being totally white and the background (the background isn't an image or geometry, is just non-existent) completely black.
Or make the geometry totally white with not shadows or lights at all, and the background totally black.

I know that in Blender Render you can simply make a Shadeless object texture by pressing the button with the same name and reducing the reflection of the same geometry.

David
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beavoru
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3 Answers3

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Here is a node setup for a shadeless material:
Nodes for answer

If you use just an emission shader the object produces light. So it still is not shadeless as it is casting light on other objects. To make it shadeless, you must make sure it sends light only to the camera. To do this, add mix shader with the emission shader plugged in the bottom node socket. Leave the mix shader's top node socket empty (or plug in a holdout shader if the empty socket bothers you). Then plug the is camera ray from a light path input node into the factor of the mix shader.

PGmath
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Adrians Netlis
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  • And the cool thing with this technique is that if you want your material to cast diffuse rays on other objects (for example if the shadeless object has its lighting baked but you want it to behave in the scene like it was a diffuse), you can plug a diffuse at the top and you will get this Global Illumination effect on the other objects, which you couldn't get by simply unplugging boxes in the object's Cycles Settings. Of course you need to plug the albedo in the diffuse, not the baked light. – ChameleonScales Jul 14 '17 at 00:58
  • On the second shader before the mix you should add a transparent shader, for me if not applied it created shadow on objects that are closer to the element that contains this specific material. – andrepazleal Aug 02 '17 at 18:49
  • its important that the emission shader is the second shader input to the mix shader, i had that wrong whoopse – ThorSummoner May 11 '20 at 21:14
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Another solution would be to assign a Holdout material to the object, as well as assign the material a unique Pass Index.

Then in the compositor you can grab the mask from the Pass Index and mix the white via the mask and an Alpha Over node. The holdout is good as it doesn't add colour bounces to the scene via indirect lighting. The object still does cast a shadow though.

Screenshot of setup

Todd McIntosh
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Already fixed it! i just created a new material directly in the node editor of cycles, then erased the first box and replaced it for 'Emission' and it worked! pretty easy if you need a quick solution :)

beavoru
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