Rendering matcap with ambient occlusion using blender internal render and cycles I'm using matcaps as materials most of time, using blender internal render and cycles with nodes or without, by making the material shadeless and setting the mapping coordinates to normal.
I want ambient occlusion to affect the final render.
Enable the Ambient Occlusion in the World section of the properties panel. Set it to Add.

Create a new material: "Ambient".
Set the Diffuse Intensity to 1, and the Color to (1, 1, 1). Rendered view will show the ambient occlusion of the material.

Create a new material: "mixedMaterial". Assign it to the mesh.
Enable nodes, add the "Ambient" Material, the "Matcap" Material and combine them with a Color Mix node. Set the Mix nodes mode to Multiply.



This is the result.