Reference: drawRect
drawRect(v, ❨w, h❩) draws a rectangle at v ∈ R^2 with width w and height h in the current 2D visualization window. drawRect(v, ❨w, h❩, s) draws a rectangle at v ∈ R^2 with width w and height h in the current 2D visualization window using the style (CSS) s. All numbers refer to the visualization window's coordinate system.