Abstract: A game system includes a game apparatus and a controller, and the controller is furnished with an acceleration sensor. For example, a player performs a boxing game according to an acceleration input by throwing a hook or straight punch while holding the controller. When it is determined that an acceleration input is started, it is assumed that the kind is a straight although the kind of the input has not been identified yet, and a drawing of a glove object moving along a path of a straight is started. When it is determined that the kind is a hook on the basis of the acceleration acquired thereafter, the glove object moving along a hook path is drawn.

Abstract: The game apparatus obtains angular velocity data and acceleration data from an input device equipped with at least an angular velocity sensor and an acceleration sensor, and determines whether or not a ball has been thrown in accordance with the angular velocity data. When it is determined that ball-throwing is fulfilled, the game apparatus calculates the intensity of swinging the input device and a curve amount. The game apparatus applies a force and a curve to a ball in accordance with the calculated intensity of swinging and the curve amount, and performs a process of causing the ball to move and curve in a predetermined direction.

Abstract: The game apparatus obtains angular velocity data and acceleration data from an input device equipped with at least an angular velocity sensor and an acceleration sensor, and determines whether or not a ball has been thrown in accordance with the angular velocity data. When it is determined that ball-throwing is fulfilled, the game apparatus calculates the intensity of swinging the input device and a curve amount. The game apparatus applies a force and a curve to a ball in accordance with the calculated intensity of swinging and the curve amount, and performs a process of causing the ball to move and curve in a predetermined direction.

Abstract: A repeated determination of a magnitude of a change amount vector with respect to a first threshold value is made. When it is determined that the magnitude is equal to or larger than the first threshold value, predetermined processing is executed, a swinging direction in which an input device is swung is calculated, and intersection of the swinging direction with a second threshold value is determined. After it is determined that the change amount vector intersects with the second threshold value, further, whether or not the magnitude of the change amount vector is smaller than a third threshold value is determined. After the magnitude of the change amount vector is determined to be equal to or larger than the first threshold value, the first threshold is not tested again until the magnitude of the change amount vector is smaller than the third threshold value.

Abstract: The game apparatus obtains angular velocity data and acceleration data from an input device equipped with at least an angular velocity sensor and an acceleration sensor, and determines whether or not a ball has been thrown in accordance with the angular velocity data. When it is determined that ball-throwing is fulfilled, the game apparatus calculates the intensity of swinging the input device and a curve amount. The game apparatus applies a force and a curve to a ball in accordance with the calculated intensity of swinging and the curve amount, and performs a process of causing the ball to move and curve in a predetermined direction.

Abstract: Operation data is obtained from an input device and is stored into a memory, and initial state data indicating an attitude or a position of an object in a virtual game world is calculated with predetermined start timing using acceleration data included in the obtained operation data. Depending on acceleration data included in operation data sequentially obtained on and after the start timing, change amount data for sequentially changing the attitude or position of the object over time is calculated. Thereafter, the attitude or position of the object disposed in the virtual game world, depending on the initial state data, is changed, depending on the change amount data, to perform a game process of controlling a motion of the object.

Abstract: Data obtaining means repeatedly obtains acceleration data. Acceleration vector generation means generates first acceleration vector in accordance with first acceleration data obtained by the data obtaining means, and generates second acceleration vector in accordance with second acceleration data time-sequentially obtained by the data obtaining means following the first acceleration data. The cross product direction calculation means calculates a direction of a cross product between the first acceleration vector and the second acceleration vector. The swing direction identification means identifies a swing direction in which the input device is swung in accordance with the direction of the cross product.

Abstract: First, operation data is acquired from an input device that is operated by a user. Next, a target is configured, by utilizing the operation data, within a predetermined range which is frontward in a forward direction of a course where a user object should move along and which is defined based on the course. Next, a moving direction of the user object is determined based on a position of the user object and a position of the target. Next, the user object is moved toward the moving direction determined by a moving direction determining means.

Abstract: The game apparatus obtains angular velocity data and acceleration data from an input device equipped with at least an angular velocity sensor and an acceleration sensor, and determines whether or not a ball has been thrown in accordance with the angular velocity data. When it is determined that ball-throwing is fulfilled, the game apparatus calculates the intensity of swinging the input device and a curve amount. The game apparatus applies a force and a curve to a ball in accordance with the calculated intensity of swinging and the curve amount, and performs a process of causing the ball to move and curve in a predetermined direction.

Abstract: A musical piece correction apparatus corrects a sounding timing (note-on timings) of a sound constituting apart of a musical piece. First, the musical piece correction apparatus reads, from storage means, music performance data indicating sounding timings in the musical piece. Next, the musical piece correction apparatus sets a plurality of reference timings (grids) in a performance period of the musical piece, and sets, for each reference timing, a reference period (area) including said each reference timing. At this point, from among sounding timings included in the reference period, a nearest sounding timing to said each reference timing is selected, and the selected sounding timing is corrected so as to coincide with said each reference timing.

Abstract: When a music performance game starts, the user selects a part to be assigned to himself/herself. When the selection of the assigned part is completed, an ensemble starts. When the ensemble starts, the user can participate in the ensemble by performing an input operation corresponding to the assigned part. During the ensemble, history data representing the user's musical performances in chronological order is generated and stored in an external main memory. When the ensemble ends, the user can play again, changing assigned parts. At this time, as for the part currently selected by the user, the instrument is played based on the user's input, while the history data representing the user's current musical performances in chronological order is generated. Of the other parts, as for the parts that the user has selected earlier, the instruments are played automatically based on the history data.

Abstract: First determination means determines at a unit time interval whether or not a magnitude of a change amount vector is equal to or larger than a first threshold value. When it is determined that the magnitude of the change amount vector is equal to or larger than the first threshold value, predetermined processing is executed. Also, when it is determined that the magnitude of the change amount vector is equal to or larger than the first threshold value, a swinging direction in which an input device is swung is calculated, and whether or not the change amount vector which shifts in a direction opposite to the swinging direction intersects with a second threshold value is determined by second determination means. After it is determined that the change amount vector intersects with the second threshold value, further, whether or not the magnitude of the change amount vector is smaller than a third threshold value is determined by third determination means.

Abstract: A musical piece correction apparatus corrects a sounding timing (note-on timings) of a sound constituting apart of a musical piece. First, the musical piece correction apparatus reads, from storage means, music performance data indicating sounding timings in the musical piece. Next, the musical piece correction apparatus sets a plurality of reference timings (grids) in a performance period of the musical piece, and sets, for each reference timing, a reference period (area) including said each reference timing. At this point, from among sounding timings included in the reference period, a nearest sounding timing to said each reference timing is selected, and the selected sounding timing is corrected so as to coincide with said each reference timing.

Abstract: A game system includes a game apparatus and a controller. The controller is furnished with an acceleration sensor for detecting accelerations in at least two axis directions. Game processing corresponding to the kind of an acceleration input by means of the controller is executed. For determining the kind, reference timing when acceleration in a first-axis direction is below a threshold value to take on a minimum value is detected. Then, it is determined whether or not an angle between acceleration change vectors before and after the reference timing is equal to or more than a predetermined angle. When the angle is not equal to or more than the predetermined angle, it is determined that the acceleration input is an acceleration input in any one of the two-axis directions, and when the angle is equal to or more than the predetermined angle, it is determined that the acceleration input is an acceleration input in a direction including the two-axis directions as components.

Abstract: Operation data is obtained from an input device and is stored into a memory, and initial state data indicating an attitude or a position of an object in a virtual game world is calculated with predetermined start timing using acceleration data included in the obtained operation data. Depending on acceleration data included in operation data sequentially obtained on and after the start timing, change amount data for sequentially changing the attitude or position of the object over time is calculated. Thereafter, the attitude or position of the object disposed in the virtual game world, depending on the initial state data, is changed, depending on the change amount data, to perform a game process of controlling a motion of the object.

Abstract: A game system includes a game apparatus and a controller, and the controller is furnished with an acceleration sensor. For example, a player performs a boxing game according to an acceleration input by throwing a hook or straight punch while holding the controller. When it is determined that an acceleration input is started, it is assumed that the kind is a straight although the kind of the input has not been identified yet, and a drawing of a glove object moving along a path of a straight is started. When it is determined that the kind is a hook on the basis of the acceleration acquired thereafter, the glove object moving along a hook path is drawn.

Abstract: A game system includes a game apparatus and a controller. The controller is furnished with an acceleration sensor for detecting accelerations in at least two axis directions. Game processing corresponding to the kind of an acceleration input by means of the controller is executed. For determining the kind, reference timing when acceleration in a first-axis direction is below a threshold value to take on a minimum value is detected. Then, it is determined whether or not an angle between acceleration change vectors before and after the reference timing is equal to or more than a predetermined angle. When the angle is not equal to or more than the predetermined angle, it is determined that the acceleration input is an acceleration input in any one of the two-axis directions, and when the angle is equal to or more than the predetermined angle, it is determined that the acceleration input is an acceleration input in a direction including the two-axis directions as components.

Abstract: An image generation system, program, and information storage medium can realistically represent reflection of light on a given object or topographic surface with a reduced computation load. The image generation system includes a section which assigns, to a given object or topographic surface disposed in a virtual three-dimensional space, a virtual object which has at least one of nonuniform brightness or color and is used for representing a light reflection effect on the object or topographic surface; a section which determines a position of the virtual object so that the virtual object moves to follow a virtual camera or player's character, and disposes the virtual object at the determined position; and a section which generates an image of the virtual three-dimensional space viewed from the virtual camera by performing translucent blending processing of the object or topographic surface and the virtual object assigned to the object or topographic surface.

Abstract: An image generation method includes: generating a two-dimensional image by perspectively transforming a virtual three-dimensional space relative to a predetermined viewpoint at a given instant; determining a corresponding position to a representative point of a waterdrop on the two-dimensional image depending on a position at which the waterdrop exists in the virtual three-dimensional space or a position at which the waterdrop is to be displayed in a display image; determining a reference position on the two-dimensional image corresponding to a vertex or a configuration point which forms the waterdrop, by using reference information relative to the corresponding position to the representative point on the two-dimensional image, the reference information being previously determined for the vertex or the configuration point forming the waterdrop; and linking the determined reference position with the vertex or the configuration point forming the waterdrop and mapping at least a portion of the two-dimensional im

Abstract: An image generation system, program, and information storage medium can realistically represent reflection of light on a given object or topographic surface with a reduced computation load. The image generation system includes a section which assigns, to a given object or topographic surface disposed in a virtual three-dimensional space, a virtual object which has at least one of nonuniform brightness or color and is used for representing a light reflection effect on the object or topographic surface; a section which determines a position of the virtual object so that the virtual object moves to follow a virtual camera or player's character, and disposes the virtual object at the determined position; and a section which generates an image of the virtual three-dimensional space viewed from the virtual camera by performing translucent blending processing of the object or topographic surface and the virtual object assigned to the object or topographic surface.