1. Home
2. Docs
3. PopcornFX v2.15
4. Scripting reference
5. Samplers
6. Curve sampler

# Curve sampler ### Sampling functions

 Return type Description `float#` `SamplerName.sample(float cursor)` Samples the curve at coordinate `cursor` on the horizontal axis.The return type is a `float` vector whose dimension matches the curve dimension. A 1D curve will return a `float`, 3D curve will return a `float3`, etc… `float` `SamplerName.sampleCDF(float cursor)` Treats the curve as a Probability Density Function (PDF), and samples its Cumulative Density Function (CDF) at coordinate `cursor` on the horizontal axis.Only works for `float` curves (single channel / 1D). Useful to get custom random distributions by doing `Curve.sampleCDF(rand(0,1))` `float#` `SamplerName.derive(float cursor)` Computes the derivative of the curve sampler curve at coordinate `cursor` on the horizontal axis.Return type is a `float` vector whose dimension matches the curve dimension. Each `xyzw` element of the result will contain the derivative of each of the separate curve components. `float#` `SamplerName.integrate(float cursorBegin, float cursorEnd)` Computes the integral of the curve sampler curve between coordinates `cursorBegin` and `cursorEnd` on the horizontal axis.Return type is a `float` vector whose dimension matches the curve dimension. Each `xyzw` element of the result will contain the integral of each of the separate curve components.

Disclaimer: These are describing the reference implementation. When using attribute samplers, the behavior of these functions can vary depending on the implementation in the game-engine where the effect is loaded.