Skirt Curve Calculator
I got tired of always guess-timating how much to curve the waist and hem of different skirts, and still have them turn out imperfect. So I used Math to calculate the depression when a conical frustum (i.e. a sliced off cone) is flattened into a 2D sector. Here is the online graphing calculator: https://www.desmos.com/calculator/68whiupw78
To use, simply input the length of the waist (w), hem (h) and length (l) of your skirt. You can then use the graph to estimate the amount of curving mathematically needed. Adjust the wasit and hem accordingly to how you split the skirt.
But now that I have the perfect mathematical curve, how do darts fit into the equation? I get that darts are used to "bring in" the waist. So on this perfect sector, I am going to make some cuts and move the shape apart so I can sew darts to bring it back together again?