loop), and open-ended splines, with their tangents specified at
their endpoints.
Also change constraint solver matrix size to 1024, on the theory
that a power of two will generate better array indexing, and
replace fabs() with my own function that for some reason is
faster.
[git-p4: depot-paths = "//depot/solvespace/": change = 2055]
point-coincident constraints and the entity- or group-generated
constraints. Also fix a bug where a dragged point was not released
when the mouse pointer left the window.
[git-p4: depot-paths = "//depot/solvespace/": change = 2045]
