Design
Time controls exist alongside the existing spatial controls.
The first button on the brings up the Date and Time Options (see below).
The time bar represents the span between the start and end times and contains a draggable playhead of the current position. Hovering or moving the playhead displays a tooltip with the current time. For ranged play, dragging the tail of the playhead expands the range of time displayed on the map at any given moment.
The controls on the right are Start, which returns to the start of the animation, Play, Fast-forward, which is effectively a double-speed play button, and End, which skips to the end of the animation. Like elsewhere in GXP, each control should have a tooltip.
During ranged play, collapsing the tail into playhead results in a fixed (unranged) playhead.
When Play or Fast-forward are selected, they are replaced with a Pause button.
If the "Loop animation" option is selected in the Animation Options (below) then a Loop control is included and active by default.
Tick marks on the time bar may be used to indicate that features occur at those times.
The time range specifies the start and end times of the animation. Selecting a date field should display a calendar widget. The defaults should be the earliest and latest points in the data.
The animation options allow for defining the interval of play. For example, features spanning three hours within the data should be displayed per second of playback.
This design adds a timeline component to the bottom of the current GeoNode map composer. From here (1.0) users can configure which layers are displayed in the timeline, filter those layers to narrow what is displayed in the timeline, and add notes to the map and/or timeline.
The range of what is displayed on the timeline (and, by extension, on the map above) is controlled by a range control on the left of the timeline (2.0) that also includes a play button. The center of the timeline should synchronize with the playhead in the time controls The play/stop actions and the range control (if the ranged play control is activated) should also synchronize.
Selecting an item from the timeline should recenter the map to include the corresponding feature within the map extent and open up the corresponding pop-up on the map. If no geometry corresponds to the selected item on the timeline (as may be the case with some notes) then the pop-up should open above the timeline item (or as an unanchored pop-up, depending on implementation concerns).
To support storytelling in temporally-enabled maps, we'll be allowing users to add "events" or "notes" layers to maps. These are drawn by the user free-hand, rather than loading a database table etc. Other than their fixed schema and editability, these layers are similar to other datasets in MapStory - they can be animated, show up on the timeline, allow styling, etc. See animated demonstration of notes.
For implementation details on notes layers, see NotesLayers.
As shown in the animation, the user first chooses an item from the Notes menu (1.2a below). If a geographic option is selected (point, line, or polygon) than the user is prompted (ideally with a tooltip on the cursor) to draw the feature on the map, then a popup appears (3.0b below) with fields for title, description, start date and (optionally) end date; if the option selected is an event, then an unanchored popup (similar to 3.0b) appears. Once a note is created it appears in the timeline and (if it corresponds to a geographic feature) on the map as well.
Date and time fields should accept years, months, and days at whatever resolution desired. In effect, it should be possible to add only a year, only a year and month, a full date, or a full date and specific time without being prompted for more specific details. For example, adding an event for January 1904 should not require specifying a date and time.
Again, as shown in the animation, selecting a note as someone with authorship permissions brings up a popup with an edit feature (3.0c above) that provides a delete option if the edit state (3.0b) is activated. Deleting a note should prompt for confirmation.