To sample occlusion in Turtle, the shader called ilrOccSampler should be used. Under the Outputs roll-out, disable Normals and enable Custom. Custom can be used to output any shader or shading network. Press the connection button and connect an ilrOccSampler. Also change the Background Color to white, since in this case we want all areas outside the uv-regions to be white (unoccluded).

We will use default settings on the ilrOccSampler (for information on how to optimize occlusion sampling, see the tutorial Ambient Occlusion). We also change the sampling algorithm from Normal Sampling to Super Sampling (Render Tab -> Sampling -> Sampling Algorithm). Now make sure Surface Transfer is selected as the Render Type, and then hit the render button.

It's now time to apply the occlusion map to the lowres rifle. In the following render we have used the same ilrOccSampler as above on the highres model, and used the occlusion map texture on the lowres model:

In the final render we will combine the normal map and the occlusion map in the same shader. We connect the occlusion map to the Ambient Color attribute on the Blinn shader. By adding an ilrOccData node between the file node and the Blinn, we can use the Environment attribute on the ilrOccData node to adjust the amount of ambient light. The shading network should then look like this:

Finally change the Render Type from Surface Transfer back to Render and hit the render button. In this render we have also enabled shadows:

• Back to Setting up Surface Transfer
• Back to Transferring Normal
• Continue to Quick Guide