Try to add shader includes and make reuseable light rendering functions #199
Description
Right now many shaders only differ by their vertex layouts. Tons of duplicate code. Could make a light rendering function that could be reused on many of the shaders. Also could define all the shader constants once like in the old DX11 renderer. Need to figure out how to make the includes work with the shaderc wrapper Silk.NET provides.
If it doesn't have support for that just make our own include system with string.Replace. Maybe add a few more special characters around the includes to make sure it doesn't accidentally delete real code or comments. Make sure the include code is recursive, by keep a list of included files to detect loops.