CMYK halftone

Controls

cell

Screen pitch in source pixels. Coarse enough and the rosette of four screens becomes visible to the eye

angle

Turns all four screens together. Their angles relative to each other stay classic — that is what makes a rosette, not moiré

black

How much of the grey under a colour is printed with black ink instead of all three. At zero the shadows are a muddy triple mix

paper

A colour, #ffffff by default.

contrast

A number from -1 to 1, 0 by default.