Introduction

Lighting is a very important topic in rendering, standing equal to modeling, materials and textures.

The most accurately modeled and textured scene will yeld to poor results without a proper lighting scheme,while a simple model can become very relistic if skillfully lit.

Lighting, sadly, is often overlooked by the unexperienced artist who commonly believe that, since real world scene are often lit by a single light (a lamp, the sun, etc.) a single light would do also in computer graphics.

This is false because in the real world even if a single light source is present the light shed by such source bounces on objects an is reirradiated all over the scene making shadows soft and shadowed region not pitch black but somewhat lit.

The physics of light bouncing is simulated by Ray Tracing renderers and can be simulated within Blender by resorting to the Radiosity (SEE) engine.

Ray tracing and radiosity are slow processes. Blender can perform much faster rendering with its internal scanline renderer. A very good scanline renderer indeed. This kind of rendering engine is much faster since it does not try to simulate the real behaviour of light, assuming many simplifying hypothesis.

In this chapter we will analyze the different type of lights in Blender and their behaviour, we will analyze their strong and weak points, ending with describing some basic 'realistic' lightning scheme, known as the three point light method, as well as more advanced, realistic but, of course, CPU intensive, lightning schemes.