# Rain Sample | [**View Fullscreen**](https://matgraph.unigine.com/SampleRain_2.21/fullView) | |---| This material graph sample demonstrates how to create an effect of raindrops on a surface. Raindrops are defined by changing material's roughness and normal maps applied with accordance to the animated mask. The mask is created from a time offset texture (*drops_offset*) and a linear gradient texture (*drops_bump*) defining the intensity of each raindrop. ![](result.jpg) *The result*