# Variable Rate Shading

Variable Rate Shading for the Unity engine: https://github.com/eldnach/vrs-edge/tree/main This renderer feature uses the Sentis API to import and execute a Sobel Edge Detection model. The output of the model will be converted to a shading rate image, which can be used to optimize the performance of render passes. Setting a uniform (screen-wide) 2x2 shading rate results in visual artifacts when zoomed:

By applying edge detection to the shading rate, visual fidelity is greatly improved:

Measuring GPU timing of a Volumetric Lighting pass using VRS:

Shading Rate	GPU Time (Volumetrics)
Uniform 1x1	~6.4 ms
Uniform 2x2	~1.6 ms (75% faster)
Uniform 4x4	~0.5 ms (92% faster)
Edge based	~4.1 ms (35% faster)