Class nokia.maps.map.component.panning.KineticMovement
Class Summary
This class represents the state of a kinetic movement as returned by the method
startMovement() of nokia.maps.map.component.panning.Kinetic.
A kinetic movement consists of two phases: move and slide. In the first, each move
of the map is recorded (duration and direciton), in the second, the map has been released,
but continues to move at a diminishing speed in the previously recorded direction until
it stops.
Extends
nokia.maps.map.component.Component.
Method Summary
addObserver
(key, callback, [context])
: nokia.maps.util.OObject
This method registers an observer for the property named by the caller.
attach
(mapDisplay)
This method will be invoked when the component is attached to a map and is not meant to be called directly.
destroy
()
This method is called from Display when Display is destroyed.
detach
(mapDisplay)
This method will be invoked when the component is detached from a map and is not meant to be called directly
get
(key)
: Variant
This method retrieves the value of the property with the name provided by the caller.
getId
()
: String
This method retrieves the unique identifier of the component.
remove
(key)
: nokia.maps.util.OObject
This method removes the property with the name provided by the caller.
removeObserver
(key, callback, context)
: nokia.maps.util.OObject
This method removes the observer for the property named by the caller.
set
(nameOrObject, [value, [force]])
: nokia.maps.util.OObject
This method sets property values, using the property names and values supplied by the caller.
Field Summary
Boolean
aborted
This property indicates if the given instance of
KineticMovement has been aborted, so the slide phase did not occur or was not completed (true).
nokia.maps.util.Vector3D
direction
This property holds the current normalized direction vector in the movet and slide phases.
Boolean
enabled
This property is used by the owner kinetic component to enable or disable the given kinetic movement, because only one kinetic movement at a time can be ongoing.
Boolean
finished
This property indicates if the given instance of
KineticMovement has finished (true) or not (false).
Number
fps
This property is provided for information only and represents the real rendered number of frames per second, which (in the best case) is epxected to be the same as the
maxFps.
Number
fraction
This property represents the speed reduction of the map in the slide phase as percentage of the display diagonal per second.
Number
fractionHz
This property holds the frequency with which the value of
fraction is applied to map movment speed in the slide phase.
Number
frames
This property acts as the frame counter.
nokia.maps.map.Display
mapDisplay
This property holds a reference to the
map.Display instance to which the given component belongs.
Number
maxFps
This property holds the maximum frame frequency rate (frames per second) to be used in the slide phase.
Number
maxSpeed
This property holds the maximum speed of the sliding movement of the map used to calcuate the value of
fraction.
Number
minSpeed
This property holds the minimum speed of the sliding movement of the map used to calcuate the value of
fraction.
Boolean
movementPhase
This property indicates if the given instance of
KineticMovement is in the move phase (true) or not (false).
nokia.maps.map.component.panning.Kinetic
owner
This property holds a reference to the kinetic component that is the owner of the given
KineticMovement.
Boolean
slidingPhase
This property indicates if the given instance of
KineticMovement is in the slide phase (true) or not (false).
Number
speed
This property holds the current speed in pixels per second in the move and slide phases.
Number
stopSpeed
This property indicates the slowest permissible map movement speed in the slide phase in pixels per second.
Direct Inheritance
Indirect Inheritance
Field Detail
Boolean
aborted
This property indicates if the given instance of
KineticMovement
has been aborted, so the slide phase did not occur or was not completed
(true). If the kinetic movement has not been aborted, the property
holds the value of false.
nokia.maps.util.Vector3D
direction
This property holds the current normalized direction vector in the movet and slide
phases.
Boolean
enabled
This property is used by the owner kinetic component to enable or disable
the given kinetic movement, because only one kinetic movement at a time
can be ongoing.
It is possible to observe this property to detect if a movement is disabled
by another one. You can re-enable the movement by setting the property
nokia.maps.map.component.panning.Kinetic#current back to it,
but be aware that endless recursion may result if another component attempts
to this at the same time.
Another possibility is to observe the current property of the
owning kinetic component when a kinetic movement is disabled and attempt to
recover the desired kinetic movement as soon as current becomes
null.
Boolean
finished
This property indicates if the given instance of
KineticMovement
has finished (true) or not (false).
Number
fps
This property is provided for information only and represents the real rendered
number of frames per second, which (in the best case) is epxected to be the same
as the
maxFps.
Number
fraction
This property represents the speed reduction of the map
in the slide phase as percentage of the display diagonal per second.
This means that a value of 0 causes an endless slide, while a value
of 1.0 should stop the map within one second. However, because the
fraction is not applied only once per second, it is not linear and
the effect of the fraction is stronger in the early stages of the
slide phase but weaker later. In reality, it is the value of 3.0
(the default) that stops the map within approximately a second.
As a side-effect, the property
stopSpeed is relatively
unimportant.
Number
fractionHz
This property holds the frequency with which the value of
fraction
is applied to map movment speed in the slide phase. By default, this occurs 15
times per second (15 Hz). The lower the value of fraction, the
more linear the frequency and the less smooth the deceleration, conversely, the
higher the fraction value, the more realistic the sliding movement.
However, a frame rate below the fraction frequency leads to a
jerky sliding movement. The higher the fraction frequency, the
smaller the fraction effect, so reducing the fraction frequency
parallel a reduction in the value of fraction itself.
Number
frames
This property acts as the frame counter. Whenever a new frame for the slide phase
is rendered, the value of this property is incremented. The property is helpful
when monitoring the frame frequency (fps). For example, you might wish to observe
this property and log its value to the console on every 10th or 20th call.
Number
maxFps
This property holds the maximum frame frequency rate (frames per second) to be
used in the slide phase. The value helps reduce CPU usage, as even on the most
powerful devices a rate of more then 100 frames per second has no noticeable
effect.
Number
maxSpeed
This property holds the maximum speed of the sliding movement of the map
used to calcuate the value of
fraction. Note that the property has
no effect to the real movement speed of the map.
Note that to modify maxSpeed, you must first overload the
method updateSpeedLimits(), which updates maxSpeed
in every frame.
Number
minSpeed
This property holds the minimum speed of the sliding movement of the map
used to calcuate the value of
fraction. Note that the property has
no effect to the real movement speed of the map.
Note that to modify minSpeed, you must first overload the
method updateSpeedLimits(), which updates minSpeed
in every frame.
Boolean
movementPhase
This property indicates if the given instance of
KineticMovement
is in the move phase (true) or not (false).
readonly
nokia.maps.map.component.panning.Kinetic
owner
This property holds a reference to the kinetic component that is the owner of
the given
KineticMovement.
Boolean
slidingPhase
This property indicates if the given instance of
KineticMovement
is in the slide phase (true) or not (false).
Number
speed
This property holds the current speed in pixels per second in the move and slide
phases.
Number
stopSpeed
This property indicates the slowest permissible map movement speed in the
slide phase in pixels per second. The map movement is stopped as soon as
its speed equals or becomes lower than the value of this property. This
is necessary, because the formula used to reduce the map movement speed
does not guarantee the speed to reach zero. The value of this property
must not be set to zero.
Note that to modify stopSpeed you must first overload the
method updateSpeedLimits(), which updates stopSpeed
in every frame.