Understanding how rendering actually works is very complicated. It’s like when a real movie is being shot, the actors and props are all in place for the shot to be taken. But imagine there was no light. Lights being the most critical part of shooting a movie – the shot cannot be taken without it. Same goes for animated movies. Creating all the different elements of a scene, complete with the tiny details and then putting them all together on a screen to create a scene. Rendering adds the final touches of lights before the scene can be completed. Once a scene is completed, the rendering process starts which is ultimately the finalization of that particular scene.
Getting this type of rendering done on just one scene at that time was not very cost or time effective. There were not enough resources and with the limitations in technology, rendering was a challenge. Then came path tracing which included lights and shadows from original sources. This was able to produce realistic results which arguably wasn’t even necessary as it was an animation not a real-life movie.
Keeping these technological aspects and challenges in mind, even Ice Age is now 14 years old. The advancements since then have grown and become so sophisticated that it can become unbelievable. The best part is that it is still getting better. Animators now have access to better software which makes their lives much easier when they work on a certain project. It is quite obvious that technology has been advancing depending on the needs of the people. So better and new ways are being created to ease the pain of the animators.