2D Lighting Effects
Introduce "s2dLight" objects which, similar to their 3D equivalents, can be of the ortho, point, or spot type, and have a strength value to cast less light at a farther distance.
Unlike the 3D implementation, use shadow volumes, so that only the far faces begin the shadow, and for enhanced visual quality. Off-screen objects should still have volumes created for them, for lights that are even farther off-screen and could project light into the visible area. Also, not all objects should cast shadows, for example a door in the background of a room shouldn't put part of the wall next to it in shadow.