Precise selection is one of the key difficulties of touch-based interaction. In some cases (such as interacting with a map-based interface), precise selection is crucial for the correct specification of information. This work investigates the difference in user input error and speed for line drawing tasks using touch and mouse-based interaction. A parameterized method of solving the nearest-point-on-a-curve problem was developed in order to obtain a quantifiable error difference between mouse and touch-based interaction for line drawing tasks. A user study was conducted and determined that mouse-based interaction occurs at a slower rate of speed and results in less error than touch-based interaction for line drawing tasks.