NPR Shader Development

Over the past couple of months I have been working to combine multiple NPR shading effects into an individual shader that can be customized to achieve a wide variety of visual aesthetics.

What is an NPR Shader?

NPR is an acronym that stands for Non-Photoreal Rendering. Unlike most shaders in animation and games, which often try to render an image resembling real life, non-photoreal rendering tries to replicate artistic processes and visual effects that are not based in the real world.

Photoreal Shading

2 Tone Color Ramp

Non-Photoreal Shading

3 Tone Color Ramp

Non-Photoreal Shading

In the photos above, the sphere on the left has a photoreal shader, while the middle and right spheres have two different NPR shaders applied. The NPR shaders above are basic color ramps, which limit the number of colors outputted in a final render.

Individual NPR Shaders

You can find pages with documentation for individual shaders below. 

A shader that emulates the paper backing of paintings and sketchbooks.

A Cross Hatch Shader mimicking the look of cel-shaded hand drawn animation

A real-time shader that emulates the limitations of early computer graphics