Hello Alexei,
> Can you describe discontinuities with the same sign if I overlook them?
So, I found there are two types of
discontinuities
due to overlapping contours:
A) Discontinuity in sign. (i.e. there is a sudden jump from negative to positive)
B)
Discontinuity in distances. (i.e. the points that should be at infinity/spread have smaller distances)
In that image the right side is correct (generated from bitmap), and the left side has both A and B
types ofÂ
discontinuities.
What you are saying about detecting sudden jump from large negative to large
(ignore the weird lines in the image, that can be fixed). But even after fixing the
sign there are pixels inside the outline which have shortest distance to the curves
inside the outline. (basically the pixels around the overlap points to the overlapping
curve, which causes discontinuous distances). Moreover they interpolate smoothly
so there is no way to find the actual distance which will be to some curve at the border
of the outline instead of inside the outline.
Also, I looked at a library (msdfgen) which handles overlapping contours without
removing the overlaps. It works well, but it doesn't work for self-intersecting contours,
that is why I'm not sure whether it's worth implementing.
Finally, I can find and fix signs such that all points inside a shape are positive and
all points outside are negative. But I don't know how I can fix the incorrect distances
In this the point `P' has a positive sign and it points to a line inside the shape, which
is not correct, instead it should point to the corner. Moreover there is no corner in the
shape because they are two separate contours, so I think removing the overlaps is
the best way to handle this.
Thanks,
Anuj
