Coarse Pixel Shading

Coarse Pixel Shading

Karthik Vaidyanathan1, Marco Salvi1, Robert Toth1, Tim Foley1, Tomas Akenine-Möller1,2, Jim Nilsson1, Jacob Munkberg1, Jon Hasselgren1, Masamichi Sugihara1, Petrik Clarberg1, Tomasz Janczak1, Aaron Lefohn
1Intel Corporation, 2Lund University

We present a novel architecture for flexible control of shading rates in a GPU pipeline, and demonstrate substantially reduced shading costs for various applications. We decouple shading and visibility by restricting and quantizing shading rates to a finite set of screen-aligned grids, leading to simpler and fewer changes to the GPU pipeline compared to alternative approaches. Our architecture introduces different mechanisms for programmable control of the shading rate, which enables efficient shading in several scenarios, e.g., rendering for high pixel density displays, foveated rendering, and adaptive shading for motion and defocus blur. We also support shading at multiple rates in a single pass, which allows the user to compute different shading terms at rates better matching their frequency content.

Read the preprint: Coarse Pixel Shading [PDF 24.5MB]

Video: Coarse Pixel Shading [48.0MB]

Citation: To appear at High Performance Graphics 2014

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