Support for traces with non-uniform colors

[dilawar]

my source image is : https://ibb.co/S0f20Fw but i get this result : https://ibb.co/Lnn2mJc

what's the problem? Is it because of init point's selection?

Originally posted by @johnSmith1990 in https://github.com/dilawar/PlotDigitizer/issues/1#issuecomment-537042436