• Kamaldeep Singh

Deferred Rendering: Making Games More Life-Like

For a long time, graphic engineers implemented lighting in scenes using forward rendering or forward shading. Forward rendering is a direct approach where we render an object and follow it by lighting the object according to all light sources in a scene and then move on to rendering the next object. This process is repeated for each object in the scene. It is an easy process to understand and implement, but it exerts a toll on the performance parameter. Forward rendering is an intensive process and requires a high amount of processing since each rendered object has to iterate over each light source for every rendered fragment. Another downside of forward rendering is that it wastes fragment shader (FS) runs in scenes having a high depth complexity (wherein multiple objects cover the same screen pixel). This happens as a result of most fragment shader outputs being overwritten.

Another problem with forward rendering arises when there are multiple light sources. In that case the light sources tend to be rather small with a limited area of eff