Ok, i search and find this post
https://hub.jmonkeyengine.org/t/lighting-a-custom-mesh/17753
But the link with the answer is broken 
i’ll try to made it myself.
I use the triangles as ground so they always face upward.
Ok, i search and find this post
https://hub.jmonkeyengine.org/t/lighting-a-custom-mesh/17753
But the link with the answer is broken
i’ll try to made it myself.
I use the triangles as ground so they always face upward.