Look at the Scripting/Templates/fmri_mesh menu item for a script illustrating how to select the color for a mesh. The color of the background mesh is driven by your shader, and you can control that with the `mesh color()` command (which is Color/ObjectColor menu item for the user interface). Overlays are controlled with `overlaycolorname()` which maps onto the color pull down menu in the overlays panel of the user interface:

```
import gl
gl.resetdefaults()
gl.meshload('BrainMesh_ICBM152.rh.mz3')
gl.meshcolor(198,64,198)
gl.overlayload('motor_4t95mesh.rh.mz3')
gl.overlaycolorname(1, 'red')
gl.shaderxray(1.0, 0.3)
gl.azimuthelevation(110, 15)
gl.meshcurv()
```