PHYSICSENGINEINIT (Compact 2013)

3/28/2014

This structure describes the initialization parameters for a physics engine object. To create a physics engine, you must pass a pointer to this structure to CreatePhysicsEngine.

Syntax

typedef struct tagPHYSICSENGINEINIT {
    DWORD cbSize;
    DWORD dwEngineType;
    DWORD dwFlags;
    LONG lInitialVelocity; 
    DWORD dwInitialAngle;
    BYTE bXAxisMovementMode;
    BYTE bXAxisBoundaryMode;
    BYTE bYAxisMovementMode;
    BYTE bYAxisBoundaryMode;
    RECT rcBoundary;
    SIZE sizeView;
    POINT ptInitialPosition;
    SIZE sizeItem;
} PHYSICSENGINEINIT;

Members

• cbSize
  Specifies the size of the PHYSICSENGINEINIT structure in bytes. Set this value to sizeof(PHYSICSENGINEINIT).

• dwEngineType
  Reserved; set to 0 (zero).

• dwFlags
  Specifies the flags that control the behavior of the engine. The following values are valid:

  • 0 (zero)
    Default mode.
  • PHYSICSENGINE_FLAG_USERTIME
    User-specified time mode.

  In default mode, the physics engine reads the time from the system clock.

  In user specified time mode, you must call SetPhysicsEngineUserTime to set the time.

• lInitialVelocity
  Specifies the initial velocity of the touch gesture animation in pixels per second.

• dwInitialAngle
  Specifies the initial angle that the animation occurs at. You must specify the angle as a value in the range 0 to 65536, where 0 is -2pi radians, pointing east, and 65536 is +2pi radians. Angles increase in a counter-clockwise direction.

• bXAxisMovementMode
  Specifies the x-axis movement mode. Set this value to PHYSICSENGINE_MOVEMENT_MODE_DECELERATE.

• bXAxisBoundaryMode
  Specifies the animation behavior when the animation reaches the x-axis boundary. The following values are valid:

  • PHYSICSENGINE_BOUNDARY_MODE_NONE
    No animation.
  • PHYSICSENGINE_BOUNDARY_MODE_RUBBERBAND
    Rubber band animation.
  • PHYSICSENGINE_BOUNDARY_MODE_BOUNCE
    Bounce animation.

• bYAxisMovementMode
  Specifies the y-axis movement mode. Set this value to PHYSICSENGINE_MOVEMENT_MODE_DECELERATE.

• bYAxisBoundaryMode
  Specifies the animation behavior when the animation reaches the y-axis boundary. The following values are valid:

  • PHYSICSENGINE_BOUNDARY_MODE_NONE
    No animation.
  • PHYSICSENGINE_BOUNDARY_MODE_RUBBERBAND
    Rubber band animation.
  • PHYSICSENGINE_BOUNDARY_MODE_BOUNCE
    Bounce animation.

• rcBoundary
  Specifies a rectangle that defines the boundary. The boundary represents the entire user control.

• sizeView
  Specifies the size of the viewable region.

• ptInitialPosition
  Specifies the initial position of the top-left corner of the viewable region.

• sizeItem
  Specifies the size of an item in the control. The physics engine uses the size to determine animation stopping points. The physics engine only stops an animation on item boundaries. An item size that is less than 1 in either dimension is treated as 1. If you specify an item size of 1, the physics engine can stop at any point on an axis.

Remarks

If any member of the structure contains invalid data, CreatePhysicsEngine returns E_INVALIDARG.

Requirements

Header	physicsengine.h, winuser.h
sysgen	SYSGEN_PHYSICSENGINE

See Also

Reference

Physics Engine Structures
CreatePhysicsEngine
Touch Gestures Physics Engine Reference