摘要 |
A touch system includes a touch screen, an image-sensing device, and a processing device. The image-sensing device generates images related to objects on the touch screen at several points in time. The processing device calculates the average coordinates of the objects based on the images, and calculates the longest distance between the objects. The processing device further determines the coordinates of a drawing spot according to the average coordinates of the objects, and determines a graphical property of the drawing spot according to the longest distance. The processing device further directs the touch screen to display the drawing spot on the coordinates and with the graphical property. |