The Timeline is a MapStore tool for managing layers with a time dimension.
It makes possible to observe the layers' evolution over time, to inspect the layer configuration at a specific time instant (or in a time range) and to view different layer configurations time by time dynamically through animations.
The Timeline tool currently works only with WMS layers from GeoServer where the WMTS-Multidim extension is installed (WMS time values in WMS Capabilities is not supported yet). To use the MapStore Timeline at least GeoServer 2.14.5 is required, but the recommended version is GeoServer 2.15.2 to have a complete support for all of the features the Timeline tool can provide (e.g. the filter by viewport). From now on, the layers that the Timeline can manage will be addressed as time layers. From now on, the layers that the Timeline can manage will be addressed as time layers.
When a layer with a time dimension is added to the map, the Timeline panel becomes automatically visible and it allows the user to browse the layer over time.
Widgets and Timeline cannot be expanded on the same map at the same time. See this section to learn more about this.
The Histogram panel opens through the Expand time slider button .
In the Histogram panel some of the most relevant elements are the following ones:
A list of layers present in map with the time dimension available. It is possible to hide this list with the Hide layers names button
The relative histogram that shows the layer' data for each time in which it is defined. In order to manage the panel the user can zoom in/out on the histogram, scroll the time axis and drag the current time cursor along it
The highlighted layer is the one whose histogram is displayed on the panel.
The highlighted layer in the time layers ' list drives the time management, from now on it will be addressed as guide layer (See in the Animation Settings > Timeline Settings > Snap to guide layer option ).
Set a Time Range
In order to see a layer in a specific time instant the user can insert a data and a time in the panel, as follows:
The current time cursor changes its position according to the selected date and viceversa: when the user drag that cursor along the time axis the date/time cells will update their values.
In order to observe the layers in a finite fixed time interval the user can set a time range through the Time range button . A date/time control panel opens to set the range limits either by directly entering values in those cells or by dragging the limits cursors along the histogram time axis, as follows:
Show times available on map
Sometimes you might be interested to show in the timeline histogram only the times instants currently visible on the map, especially when you are exploring a big data set. This feature can be enabled by clicking the Map Sync button . When this tool is active the timeline will show only the times of the features available in the current map viewport.
Map Sync feature need at least GeoServer 2.15.2
The user can start a time animation by using the timeline tool through the following buttons (by default the animation of layers in map is based on time values related the guide layer, see the Animation Settings section > Timeline Settings > Snap to guide layer option):
In order to start the animation the user can click on Play button . Once the animation is started, the temporal layers in map are updated accordingly and the user can see the animation progress also in the timeline histogram. Following the sequence of steps, the cursor will shift each time to the next step in a certain time interval, the frame duration.
Through the Stop button the user can stop the animation and the current time cursor remains in the last position reached.
The Step backward button and the Step forward button allow the user to change the current time. Therefore, by clicking on one of them, the cursor changes its position (to the previous or the next step) on the histogram, the date/time values of the control cells will be updated accordingly and the layers in map are updated too.
The user can pause the animation through the Pause button , as follows:
The user can also specify a time range. During the animation, the whole range will be shifted step by step along the time axis and, in each step, the layers in map will show data corresponding to that range of time.
The animation behavior can be customized through the Settings button . It allows the user to tune the Timeline and the Playback options.
By default, the Snap to guide layer is enabled. It allows to force the time cursor to snap to the selected layer's data.
If the time dimension of the layer has time ranges defined (start/end time) instead of time instants, the user can choose the Time interval snap point by selecting the option
End. An example of snapping to the
End point could be the following:
The user can disable Snap to guide layer to select the preferred time step through the Animation Step option. For example, the process could be similar to the following one:
The user can set the number of second between one animation frame and another through the Frame Duration and enable the Follow the animation to visualize the animation process also inside the histogram: the histogram will automatically move to follow the animation.
Enabling the Animation Range the user can bound the animation execution to a fixed time interval, the green range. The green range can be defined both dragging the play/stop cursors directly on the histogram or filling the date/time control cells of the extra panel displayed, as follows:
In order to properly set the Animation Ranger, some controls are available to help the user:
Zoom the histogram until it fits the animation's green range time extension through the Zoom to the current playback range button
Extend the animation's green range until it fits the current view range of the histogram through the Set to current view range button
Extend the animation's green range until it fits the guide layer time extension through the Fit to selected layer's range button