Show stations outside polygon on map

[rod-glover]

Currently, drawing a polygon on the map causes all but the stations inside that polygon to be removed from the map. This seems unhelpful in the case where the user wishes to alter the polygon to include more stations. It also frustrates natural curiosity.

To retain clear visualization of the stations within the polygon, either the stations outside it could be rendered with semi-transparent colours (or something similar), or the stations inside it could be rendered with an additional distinction, such as a solid black border.

[rod-glover]

Resolved in #83

[jameshiebert]

Sorry... how was this resolved in #83?

[rod-glover]

This PR is focused on station filtering. While refactoring and fixing the filtering, it was a simple matter not to apply the area filter to the list of stations displayed on the map. Area filtering is still applied to all other items, such as station counts, metadata listings, etc., and of course included in the request to the data backend.

[jameshiebert]

OK... I see how, yes, they are rendered outside of the select. The title of this issues is addressed. However, I thought that this part in the description:

stations outside it could be rendered with semi-transparent colours (or something similar)

is also important to this issue.

[rod-glover]

TL;DR: I think the polygon is enough without changing the appearance of the markers, which is costly in response time.

Let me push back on that a little. The polygon has a solid boundary and semi-transparent fill. Which stations are inside the polygon and which outside are made obvious by that. By re-rendering all the polygons outside the boundary with different colours as well, we'd incur the rendering time, which is significant. Eliminating unnecessary re-renders is what gave us the 3x speedup. We'll lose a significant part of that if we proceed this way.

Does that alter your opinion of the situation?

[rod-glover]

@jameshiebert , I stand by my most recent comment above. I would like to close this issue.