HELP determining Shape drawn by mouse?!

Hey everyone,

I’m stumped on this. I’m trying to figure out how to determine the shape drawn my a person after mouse_down event has been thrown. Currently I have an array that stores the points including the initial MOUSE_DOWN point as well as a point every 0.2 seconds until MOUSE_RELEASE then it records that point as well.

I’m trying to determine the shape drawn with a bunch of math. My initial test was to determine a circle using 4 vector points A, B, C, and D then I calculated AB, AC, DC, BD, CD, DA

and with help of the dot product i did: AB . CD + BC . DA = AC . BD

if the absolute values are equal then the points lie within a circle together… which works- but that also screws up a bunch of the other draw patterns like a basic line or something because it would fit as well…

I’m wondering if I’m on the right track… completely off track or what- Any help would be awesome!! If this is right I guess I could just do an if/else statement or whatever, with this option at the bottom to check all the others beforehand… Thoughts?