Patent ID: 7268781

Claim:
An image display control method in a game system having an image display unit for displaying a two-dimensional image obtained by perspective-projecting an image model disposed in a virtual three-dimensional space onto a perspective projection plane in a view point coordinate system of view points set in said virtual three-dimensional space; a designation unit for designating a position on the display plane of said image display unit; a detection unit for detecting the designated position of said designation unit with respect to the display plane of said image display unit; and a control unit for execution-controlling a game based on the detection signals from said detection unit and controlling said view point position or view line direction in said virtual three-dimensional space, the method comprising the steps of: setting a specific region on said perspective projection plane; detecting the designated position with respect to said display plane, which is designated by said designation unit; determining whether or not said designated position is located in said specific region; displacing said view line direction or moving the view point position based on the positional relationship of said designated position and said specific region when said designated position is not positioned inside said specific region; and finding a two-dimensional image obtained by perspective projection in the new view line direction after the displacement of said view line direction or movement of the view point position and displaying this two-dimensional image on said display device.