I am using shadow-mapping to add shadows to my world.
Currently, I use one lightsource, which means I have to draw my world twice: once in the lightview, once in the camera view.
I want to add more light sources to the world, I want at least 2 sources, maybe 3 or 4.
My world geometry is large, roughly 1M triangles, so drawing them comes at a large cost.
Are there any shortcuts I can take to avoid drawing the geometry for every light source?
Would it be possible to write to multiple depth textures in a single pass? E.g. pass several lightview matrices to a vertex shader and somehow write several framebuffers in one go?
I am using OpenGL core profile.
What I've tried: I looked at Multiple Render Targets, but it seems that every attached buffer will share the same vertex transformation, which would not help in my situation: every light view has a different transformation.