Free public beta until December 4, 2026: every course is open, no card needed. After that, the first chapter of each course stays free and full access is a one-time $39 ($19 for up to 100 founding members chosen for helpful feedback). Your progress is kept. How the beta works

foreground

In compositing, the layer drawn on top (foreground) versus the layer it covers (background).

In compositing, the foreground is the layer being drawn on top and the background is the layer underneath it; alpha compositing blends the two per pixel using the foreground's own alpha as the mixing weight.

Read the full section →

snap pen only

Graph settings

indep dep deg

grid intersections

xmin xmax ymin ymax

x-tick y-tick

Calculator