So a specular map should be black and white correct? I don't understand how to bake specular maps using cycles that are in the proper black and white form.


Bake the Specularity data, not the light interaction

According to the Wikipedia, specular maps contains the valuest that:

represents the amount of reflectivity a surface has.

These maps are used in order to give to the rendering engine the information about how the light should interact when hitting that particular pixel of the surface.

What you should bake is the data about where a surface is capable of reflecting light and where is not, and not how the light interact with the surface (Glossy color, Glossy Direct, Glossy indirect, Combined....) because these are the result of the render engine.

Let's consider a simple material made of a Diffuse and Glossy shader mixed with a musgrave texture:

enter image description here

In this case it's easy to understand that the amount of Specularity is equal to the values that go into te mix shader factor. Where is black is Diffuse (no Specularity), where is white is Glossy (Specularity).

To bake that data just use an emission shader picking the color from the cable that is going into the mix shader's input socket

enter image description here

Here's the counter-prove. The baked map is now controlling the specularity of the surface as the musgrave was doing before.

enter image description here

For complex shaders things becomes harder, you'll have to build a custom nodetree capable of exctracting the Specularity data on each passage (e.g. if you are using multiple mix shaders).

|improve this answer|||||

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for?Browse other questions tagged or ask your own question.