The InitialExpansionVelocity property specifies the rate of radius expansion for a target when the target was affected by inertia.
This property is read/write.
HRESULT put_InitialExpansionVelocity( [in] FLOAT velocity ); HRESULT get_InitialExpansionVelocity( [out] FLOAT *velocity );
The rate of radius expansion for a target when the target was affected by inertia.
Returns S_OK on success; otherwise, returns an error code such as E_FAIL.
The amount of expansion that the IInertiaProcessor exatrapolates will be detemined by the DesiredExpansion or DesiredExpansionDeceleration property. DesiredExpansion and DesiredExpansionDeceleration are mutually exclusive. If one is set, the other should be NaN. If using the DesiredExpansion property, the API will set the appropriate DesiredExpansionDeceleration value to expand the requested amount.
If inertia processing has already started, setting InitialExpansionVelocity will reset the inertia engine to the initial state with new velocity values applied.
Call this function to set the initial state of inertia. You would call this function most likely during the ManipulationCompleted event of the IManipulationProcessor or in the constructor of the IInertiaProcessor interface.
Minimum supported client
|Windows 7 [desktop apps only]|
Minimum supported server
|Windows Server 2008 R2 [desktop apps only]|
- Inertia Mechanics
- Handling Inertia in Unmanaged Code