I have put it into the joesville track as said and there it receives shadows. I have made the texture a bit brighter, to better see the shadow. But it don't casts shadows. To get it casting shadows, tag it with something like ShadowCaster=(Static, Solid) in the scn file.
I remade the objects again using very thin boxes in 3ds max and they finally received a shadow then. The (hopefully) last issue Im facing with the grass, is its transparency. Other objects from further behind are rendering through the object in the foreground. I tried the 'sorted' option in the material settings, which fixed the issue of objects from the distance rendering through the first object, but the transparency of the first object was 'covering' the object behind. I tried to check 'No Z buffer', but my objects werent showing up at all then.
Set One for the Source Blend and Zero for the Dest Blend and then select the first texture stage and check the box on the left of Chroma Color. That should solve the transparency problem.
After placing a few objects, I noticed that they have become quite shiny when facing the sun and very dark from the other side. Is there a way to reduce those effects, because its not looking very realistic.
I'm no specialist with it, but that normally can be modified by the used shader and it's settings and also the textures (have to be "albedo" maps) have an influence. And also in the scn file, you could play around with this a bit: AmbientColor=...
The diffuse color is impacting the reflection and intensity of received shadows. The other colors werent influencing my objects at all or just so slightly that i didnt notice. Unfortunately, there is no sweet spot in my case, so end up with too shiny textures or textures with barely any shadows. Ive tried to use the t1 specular map shader, once with a black and then a white-to-black gradient spec layer, but i couldnt see a difference compared to my previous attempts.
I imported the zandvoort 2017 version scn file to 3dsimed to check how studio397 has implemented the grass. they did it with 2d triangles, the bump specular map t1 shader and double sided material. I will give it another try tomorrow and see how it turns out.