I'd like to color the Board over a line using JSXGraph.
I'm drawing lines on the Board and use "polygon" to color the common space above / under these lines.
However there are cases when "polygon" is not a solution as I want to color basically the whole Board above / below these lines. (When the common space is above / below them.) Is there any way to color "above lines" or "below lines" without using "polygon"?
It seems that you are looking for the element inequality, see https://jsxgraph.org/docs/symbols/Inequality.html . You'll find examples how to use it there.