Non-Photorealistic Rendering Paige Petterson

What is NPR? Non-photorealistic rendering is a computer graphic process that focuses on enabling items to look as though inspired by paintings, drawings, cartoons and other sources that do not feature photorealism. ‘A means of creating imagery that dose not aspire to realism’ – Stuart Green

Cel-Shading Cel-shading or toon shading is a type of non-photorealistic rendering, designed to make 3-D computer graphics appear to be illustrated or drawn and coloured by hand Cel-shading is often used to mimic the style of a comic book or cartoon.  The name comes from cels (short for celluloid), the clear sheets, which were painted on for use in traditional 2D animation

NPR has been used in helping to create a number of movies and video games Tarzan Bolt Tangled Feast Paperman The Legend of Zelda: Wind Waker

Tarzan - Deep Canvas One of the unique aspects of Tarzan was its use of an innovative NPR system known as Deep Canvas.   The system was created by the production team as a 3D painting system to create sweeping background that we see in the movie.  The Deep canvas records brush strokes in 3D and created backgrounds that appeared as drawings or paintings.   The system even won an awarded a Technical Achievement Award by the Academy of Motion Picture Arts and Sciences in 2003. And has been used in a number of other Disney movies today.

Disney’s Paperman Characters and background were first created in CG, with the hand drawn art then layered over the top. This creates a very stylized CG layer underneath, with the image having a very flat look. This process also gives animators the ability to make changes since the CG layer underneath can be erased as desired.

Flowchart of work flow CG Models Stylized CG Shading Motion Vector Line/paint stroke Final Composite