void main() // Compute derivatives vec2 dUVdx = dFdx(uv); vec2 dUVdy = dFdy(uv);
In shading, derivatives represent the rate of change of a texture's UV coordinates with respect to screen space. This information is essential for accurately computing various shading effects, such as: derivative shader
In standard rendering, the GPU processes pixels in small called "quads". Even if you are only interested in one specific pixel, the hardware calculates its three neighbors simultaneously. This allows the GPU to look at the difference between the values in those pixels to determine a "slope." void main() // Compute derivatives vec2 dUVdx =
Derivative shaders are not without faults. They introduce a specific class of bugs that are notoriously difficult to debug. This allows the GPU to look at the
Derivatives can be used to detect discontinuities in depth or normals across screen space. This is frequently used for "post-process" style outlines or toon shading outlines, often cheaper than a second geometry pass.
Derivative shaders are commonly used in various fields, including: