GAME SYSTEM AND INFORMATION STORAGE MEDIUM

PROBLEM TO BE SOLVED: To provide a game system and an information storage medium, capable of generating motion information for imparting varied and real motions to an object having plural parts connected by joints with a small calculation load in real time. SOLUTION: This game system generates an image. The game system includes a motion generation processing part 114 generating the motions of the object having the plural parts connected by the joints by executing, in each the part, processing for finding rotation information of the joint of a given part of the object having the plural parts connected by the joints on the basis of external force applied to the given part and internal force applied to the given part from the adjacent parts connected by the joints. The motion generation processing part 114 sets a rotatable range to a given joint and executes processing for finding the rotation information of each joint such that the rotation is within the rotatable range.