Lighting

I've now successfully reimplemented the lighting model suggested in Markus R. Tillman's bachelor's thesis.

Lighting model, darker at the base, lighter at the tip

A simple explanation of how it works is as follows: The closer to the base of the grass, the darker it becomes. The darkness factor, so to speak, is linearly interpolated between the values of 0 and 1.5. This means that at the top of the grass blade, there will be a light color, and at the base there will be a black color.

A closer look