What program can measure the length of each zigzagging line I draw?
A ruler.
>>61377840
For example these 3 lines here, I draw them on an image on the program and it calculates the length of each line
>>61377898
Those aren't lines, they aren't straight.
>>61377945
neither are you, faggot
>>61377898
actual programs: none, but the problem is simple enough: find enough points so that the lines between them match the line itself, then sum their lengths. Coast of England problem, though.
>>61377945
who the fuck are you to say that
>>61377898
Vectorize them, calculate the lengths of the segments between the points.
Actually I just checked and inkscape can do it. Just import the image; path->trace bitmap; break apart the result into individual curves; and finally go to extensions -> visualize path -> measure.