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Using a simple cube in Blender Render, it's easy. The color of the material directly affects the baked texture (Bake Mode = Ambient Occlusion).

AO in blender render

In cycles I'm getting pure/full intensity white on the baked texture, despite the fact the material>surface>color is dark grey (.2,.2,.2). Even if I set it to pitch black, and the world surface color to black, it'll still turn out full white. (With the scene and/or world settings all at default, or not, the result is exactly the same; 100% white.)

AO in cycles

Note: I'm getting black to white gradient when I bake a proper (character) mesh. Getting no gradient is not the problem. The problem is that I don't know how to adjust the overall color/brightness of the entire map.

I just want the AO map range of color to be darker (from RGB 0 to RGB .8, instead of RGB 0 to RGB 1 as it is now). Similar to how it is in blender render.

In the end these AO maps are gonna be used on game assets. (I'm not an artist. One of the artists I work with prefers greyer AO maps because it makes the dark areas less pronounced.) I could change the brightness of the image in ps/gimp/whatever easy, or in the UE4 material, but that's a step I'd like to avoid if possible.

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    $\begingroup$ You can bake an AO map using Blender Render even if the object's materials are for Cycles. AO is calculated from the geometry, so it doesn't rely on material data. $\endgroup$
    – Mentalist
    Commented Oct 18, 2017 at 6:36
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    $\begingroup$ This white result is correct, that's how it's supposed to be. Forcing it to be different is a road to hell. AO texture carries self-shadowing data and since the cube has no crevices, there are no shadows - it's just white - the AO map is supposed to be multiplied with other textures - being white in places means no change. If the max was 0.8 instead of 1, you would be just darkening the material as a whole. Whatever you are trying to do, you are choosing the wrong method to do it. You might want to post your surfacing pipeline or process, you will get better tips how to do things. $\endgroup$
    – Jaroslav Jerryno Novotny
    Commented Oct 18, 2017 at 10:38
  • $\begingroup$ @Mentalist Thanks for the help. I'm using a cycles batch bake addon, and I'm not so great with python so it'd take me a bit too long to get the addon to work with Blender Render. I'll look into it though. $\endgroup$
    – kusogaki
    Commented Oct 20, 2017 at 5:25
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    $\begingroup$ @kusogaki I agree with Jerryno. I can also appreciate why you might want the Blender Render style AO maps for artistic effect, even if Cycles AO maps are more accurate(?) [Why they are different, and what the story is behind that I do not know, but it makes me curious.] If I may, I will suggest another possible approach, which is to use AO maps in conjunction with cavity maps, layered into one texture if you want. Cavity maps can be created with the Geometry node's "pointiness" and create detail not based on proximity shadows, but instead by how much the parts of your mesh jut out / recede in. $\endgroup$
    – Mentalist
    Commented Oct 20, 2017 at 5:50
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    $\begingroup$ Why don't you go ahead and write an answer for your question, since you seem to know the best way to answer it as it applies to you. You can include the most relevant bits from our comments, such as how "the white result is correct", how the render engines are inherently different in their AO rendering although they both use geometry, and maybe briefly mention the similarity between cavity maps and AO maps... if you're up to it. And most importantly, what approach you plan to take to get the result you're after (batch post processing of AO maps?) Then we can go ahead and close this case. $\endgroup$
    – Mentalist
    Commented Oct 24, 2017 at 1:22

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Answer: Thanks to Jerryno and Mentalist I understand now that the reason why the Cycles AO map is too bright is because unlike in Blender Render, materials in cycles don't affect AO bakes - rather a more physically correct lighting model is applied in cycles.

Other Solutions: Metalist gave me the following info/solution (unfortunately, I haven't tried either because I don't know how to get them to work in a batch bake addon I'm using): - Cycles materials can be used in Blender Render - It's possible to create a cavity map using the "Pointiness" property on the geometry node for the mesh, and combine that result with the AO map.

I'm using an addon someone made a couple years ago to bake these AO (and normals), but it only works with cycles. I'll try to get help on converting it to work with Blender Render. That, or I'll try to modify the addon to insert a semi transparent grey layer over the AO before it saves it out.

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