Nested grids #6

This work is inspired by the work "Pi et plis" (Pi and folds) by François Morellet.

The program starts by defining a main grid, it chooses between a regular grid (where each cell has the same dimensions) and a modular grid (iconic element of Piet Mondrian's painting and of the De Stijl group).

The program continues by cutting cells from the grid. It determines random lines, which, if they intersect the sides of the cells, will cut them. With each cut, it fills the resulting shapes with another grid. These shapes are added with different blending modes (xor, multiply, difference, screen and multiply) and four different colors.

Features on live mode
Key 1: set size to 1000x1000px (default)
Key 2: set size to 2000x2000px
Key 3: set size to 3000x3000px
Key 4: set size to 4000x4000px
Key D: download a PNG image of sketch (at the current size)
Key A: play a short animation (cut by cut)