Hair
If you want to render polygon hair (see Generate tab), Cinema 4D offers the Polygon Hair shader, which can be loaded into the Luminance channel of any normal Cinema 4D material.
Polygon hair is rendered similar to the way in which normal hair is rendered. Nevertheless, the Polygon Hair Shader offers only a fraction of the properties normal Hair material has to offer. The rendered quality of hair created using Hair is always much better than hair created using the Polygon Hair Shader.
If you convert a Hair object to polygons (To do so, a shape must be selected in the Type setting of the Hair object's Generate Tab) by pressing the c-key, the following tag will be created simultaneously, in which information regarding the HAIR Tangent Tags are saved:
The shader cannot function correctly without this tag. As soon as you edit the Polygon Hair, the tag will no longer be valid and will lead to unwanted results.