i still forget how to do this and always end up referring to simons tutorials from last year or looking for new ways to do it. I think for the mothman model i used the vector render method for the wireframe. but i prefer the way simon showed us, i guess its easy to forget because we only did it the once and right at the end of the year. so i decided to write out the steps and take screen shots to help me remember how to do it, then i thought i’d post it up on here since it’ll look neater on the blog than in a word document.
Create Ambient Occlusion Shader
1. In the Hypershade, create a new Surface Shader, rename to AMB_OCC_Shader. Select the renamed shader and go to Graph>Input and output Connections to show everything in the work area.

2. Then find “mib_amb_occlusion node” and drag it into the work area. Middle mouse click the AO node and drag it onto AMB_OCC_shader. Select “Other”.

3. in the Connection Editor, on the left side, highlight “outValue”. On the right side, highlight “outColor” and close the Connection Editor.

4. Select AMB_OCC_shader and in the Attribute Editor set “Samples” to 128 or 256, “Spread” 1 to 5 and “Max Distance” 1 to 5.

5. Apply material to object and Render.

Render The Wireframe
1. First duplicate AMB_OCC_shader and rename it to wireframe. Select Shader Group (if it is not visible, select Wireframe shader, then Graph>Input and Output Connections).

2. Now in the Attribute Editor, find the Mental Ray section and then find “Contours”. turn on “Enable Contour Rendering” and set “Color” to black and “Width” to 0.5.

3. Now open the Render Settings, make sure Mental Ray is selected and go to the Features tab. look for the Contours section and turn on “Enable Contour Rendering”, set “Over-Sample” to 3.

4. Look for “Draw By Property Difference” (just beneath Contours in Render Settings/Features) and turn on “Around All Poly Faces”.

5. Apply wireframe shader to object and Render.

Baking Ambient Occlusion To Texture
1. Before baking, ensure that a project is properly setup, the object is UV unwrapped, the normals are facing the correct direction and edges are hard or soft as needed.
2. With Rendering selected go to Lighting/Shading>Batch Bake option box. Ensure that “Use bake set override” is ticked, “Color Mode” is set to Occulation, X, Y Resolution and File Format are set to the required output. Setting Final Gathering to maximum will give better results.
3. Press Convert and Close to Bake texture. The baked texture can be found in the projects renderData/mentalray/lightMap folder.