Patent ID: 7834895

Claim:
A storage medium storing a game program to be executed by a computer of a game device for displaying, on a display device, an object moved around in a virtual game world, the game program instructing the computer to perform: calculating a position of the object in the virtual game world; updating trace shape information representing a shape of a trace along which the object has moved across a game field in the virtual game world based on a change in the calculated position, and storing the updated trace shape information in a memory; producing a ground image by blending together an image of the game field in the virtual game world with the trace and that without the trace based on the trace shape information; rendering the game field in the virtual game world by using the ground image; placing the object at the calculated position; and displaying the virtual game world in which the object has been placed on the display device, wherein the trace shape information is an image in which the trace shape is indicated by a color shade, and a blending ratio at which the image of the game field with the trace is blended with that without the trace and is indicated by the color shade, and wherein the trace shape information is an image indicating that a stronger color shade provides a higher blending ratio at which the image of the game field with the trace is blended with that without the trace.