Suggested settings for billboards

[iToo]

What are the suggested settings to use billboards in my scenes ?

It depends of the renderer. These are some tips:

Scanline

- For shadow maps, use the XShadow plugin.
- For raytrace shadows, be sure to assign the light in the "Shadows" rollout.
- Use "Forest Material" with any material as base.

Mental Ray

- Always assign the light in the "Shadows" rollout.
- Don't use XShadow plugin. It's not compatible with MR.
- Use "Forest Material" with a Standard Material as base, and enable "Forest Shader" checkbox in FM. This combination enables a custom shader optimized for MR and billboards.
- The "Forest Shader" parameters are found in the "Material" rollout of Forest. Use "Self-Illum factor" and "Irradiance Color" parameters to adjust the illumination of the billboards.

VRay

- Always assign the light in the "Shadows" rollout.
- Don't use XShadow plugin. It's not compatible with VRay.
- You can use "Forest Material" with any material as base, as VRayMtl.
- Enable the Indirect Illumination (GI) to get the best results.

References:

Shadows rollout
Material rollout
Forest Material
XShadow (Scanline only)
Using Shadows tutorial (Scanline only)