Game apparatus and storage medium storing game program

A computer readable non-transitory storage medium storing a gravity direction calculating program having instructions which cause causing a computer in a gravity direction calculating apparatus to calculate a direction of gravity with respect to an input device, wherein the instructions cause the computer to perform:

• an obtaining step of successively obtaining acceleration data output from a multi-axis acceleration sensor included in the input device;
• a period detecting step of detecting a movement period as being a period from start to end of movement of the input device using the obtained acceleration data;
• and
• a gravity direction calculating step of calculating a sum of acceleration vectors corresponding to one or more of the acceleration data obtained during the movement period, and determining a direction determined of a vector indicated by the sum as being the gravity direction, wherein each of the acceleration vectors is a vector whose components are acceleration values for a plurality of axes of acceleration values corresponding to axes indicated by the acceleration data and the acceleration vectors each correspond to a different point in time during the movement period.

A gravity direction calculating apparatus for calculating a direction of gravity with respect to an input device comprising:

• an obtaining logic unit successively obtaining acceleration data output from a multi-axis acceleration sensor included in the input device;
• a period detecting logic unit detecting a movement period corresponding to a start and end of a movement of the input device based on the obtained acceleration data;
• and
• a gravity direction calculating logic unit calculating a sum of at least one acceleration vector corresponding to the acceleration data obtained during the movement period, and determining a gravity direction based on a vector indicated by the sum, wherein each of the acceleration vectors is a vector whose components are acceleration values with respect to a plurality of axes of acceleration values corresponding to axes indicated by the acceleration data and the acceleration vectors correspond respectively to successive points in time during the movement period.

A computer readable non-transitory storage medium storing a gravity direction calculating program including instructions executed by a computer in a gravity direction calculating apparatus to calculate a direction of gravity with respect to an input device, the instructions cause the computer to:

• successively obtain acceleration data output from a multi-axis acceleration sensor included in the input device;
• detect a movement period corresponding to a start to an end of a movement of the input device by analyzing the obtained acceleration data,
• calculate a summed vector by summing acceleration vectors each corresponding to one or more pieces of acceleration data obtained during the movement period,
• determine a gravity direction using the summed vector, wherein the acceleration vectors each have as vector components acceleration values for each of a plurality of axes of acceleration values corresponding to axes indicated by the acceleration data and the acceleration vectors correspond respectively to successive points in time during the movement period.

A gravity direction calculating apparatus comprising:

• an input unit having a multi-axis acceleration sensor, and
• a computer executing a program instructions stored on a non-transitory memory, the computer when executing the program causes the apparatus to:
• successively obtain acceleration data output from the multi-axis acceleration sensor;
• detect a movement period corresponding to a start and end of a movement of the input device based on the obtained acceleration data,
• calculate a sum of acceleration vectors corresponding to the acceleration data obtained during the movement period, and
• determine a gravity direction from a vector indicated by the sum, wherein each of the acceleration vectors is a vector whose components are acceleration values with respect to a plurality of axes of acceleration values corresponding to axes indicated by the acceleration data and the acceleration vectors correspond respectively to successive points in time during the movement period.