[Qgis-developer] Temporal data (was QGIS GRASS Plugin Upgrade Crowdfunding)

[Nyall Dawson]

On 30 March 2015 at 18:47, Radim Blazek <radim.blazek at gmail.com> wrote:
> Hi again.

>
> I am getting convinced that the temporal data visualization support
> should be added to QGIS core. A single time navigation toolbar
> (from/to, start/stop, previous/next) and temporal support in data
> providers (QgsVectorDataProvider::getFeatures,
> QgsRasterDataProvider::block). That would allow simultaneous animation
> of temporal data from various sources in different formats (time frame
> defined by band, layer or attribute).
>
> There are already 3 plugins for temporal data management [1][2][3],
> writing another one seems misconception and wasting of resources.

+1 from me. I've also given this a lot of thought, and think that the
best solution would be in QGIS core.

I think porting the functionality from Time Manager would be a good
start, but what I would really like to see would be for QgsDataDefined
to be extended to handle animation support. This is already possible
by a combination of scale_linear and Time Manager's current time
expressions, but a better solution would be for
QgsDataDefined/QgsDataDefinedButton to allow for properties of
symbols/labels/composer items to be animated. For instance, smoothly
vary the symbol size between 2 and 4 mm between these two datetime
values.

I'd be willing to assist in coding this, but can't take the lead due
to time constraints.

Nyall