Give this a try-post your results I'd be interested to see if they're what I'd expect.

[inncubus]

http://woodgears.ca/eyeball/index.html

Just a little thing to see how good you are at estimating positions.

Comments

[midnightschilde]

6.53 I can't do the equidistant point in a triangle to save my life it seems :)

Your inaccuracy by category:

Parallelogram 7.2 14.8 12.6
Midpoint 0.0 1.4 2.0
Bisect angle 3.0 0.8 6.5
Triangle center 33.9 10.6 14.9
Circle center 2.2 2.2 3.2
Right angle 1.6 8.5 1.5
Convergence 6.1 0.0 4.1

[darkpsychosis]

2.96 ... but I think spending my day looking at polygons and geometry probably gives me a bit of an advantage.

[microphonemark]

Your inaccuracy by category:

Parallelogram 5.0 6.7 5.7
Midpoint 3.2 6.1 4.0
Bisect angle 6.0 2.2 1.0
Triangle center 8.2 5.2 8.5
Circle center 4.1 3.6 7.1
Right angle 7.3 3.1 1.1
Convergence 5.1 2.2 5.8

Average error: 4.82 (lower is better)
Triangle center let me down, but I felt I was just guessing on circle center.

I would imagine that artists have a significant advantage over me - I don't have the ability to draw geometry freehand, something I'd expect an artist to be able to do.