1. A computer-readable storage medium having stored therein a coordinate processing program for processing input coordinate data outputted from a coordinate input device, the coordinate processing program causing a computer to operate as: a second coordinate series calculator configured to calculate, on the basis of a first coordinate series indicated by the input coordinate data, a second coordinate series which represents an input trajectory having a shape smoother than a shape of an input trajectory represented by the first coordinate series; a moving amount calculator configured to calculate a moving amount of a coordinate on the basis of the first coordinate series; a moving direction calculator configured to calculate a moving direction of the coordinate on the basis of the second coordinate series; and a processing section configured to perform predetermined processing by using the moving amount calculated by the moving amount calculator and the moving direction calculated by the moving direction calculator.