I have a particle effect that renders a bunch of billboard particles over the surface of a sphere mesh. The particles and the sphere have the same color and the same material.
It's everything ok, except for the fact that when my realtime light changes its direction, the sphere changes the color accordingly, but the particles don't. They change their colors, since the particles and the sphere use the same material, but the particle normals point to somewhere else, so they don't react to the light the same way the sphere does.
Is there a way I can set the normals for my particles correctly? That means: when instancing particles in some vertex of the surface of a mesh, how can I pass the normal of that vertex to the material of the particle (so that both the particle and the mesh vertex react to the light equally)?