Okay, so I tried rendering an AO pass first through making a new layer, but I didn’t have an occlusion preset. So instead I used mia material and enabled ambient occlusion through there. Problem is, it still doesn’t show up in my render. Here’s what I’m trying to render, the distance of the floor is set to something obnoxious like 60 and there’s still no shadows…
for MIA’s ambient occlusion to work, you have to make sure ambient occlusion is enabled in the render globals, under the features tab and under the indirect illumination tabs. Even then, it’s not really meant to generate raw darkness, it’s meant to reduce ambient light in the shader.
For what you’re doing, I’d just use a mib_amb_occlusion node though in the hypershade listed under textures of the mental ray section and plug that into a surface shader. Has a lot more useful settings than the MIA’s.
Or if you want the AO to directly be baked into the shader you can multiply it into a texture or whatever