I want to illuminate a triangle mesh (from an .stl file) using only imagebased skybox lighting. When rendering an object, it appears that no shadows are cast from self occlusion. Eg. lighting a cylinder from a 45 degree angle wrt. the symmetry axis leads to a rendering where the inside of the cylinder have the same amount of illumination where realistically the light should only be able to light a part of the inside while the rest is in shadow.
Is it possible to enable casting of shadows?
Perhaps I should add that I have not computed normals or tangents for the imported .stl mesh. Is this neccesary?
Below is a codesnippet showing the setup of the vtkRenderer:
auto skyboxActor = vtkSmartPointer::New();