flyTo equivalent

[mourner]

It would be nice to port ballistic zoom-pan from llmr, as it is usually very useful in demos. I might look into it.

[incanus]

Can you give an example of this? Is this where it zooms way high, then back down to earth?

[mourner]

@incanus yep, that's it. Useful when you need to smoothly animate the view to some place no matter how far it is. E.g. it was used actively in the auto demo, and Mapbox party demo where it cycled between different places around the world. It can also rotate during animation.

[jfirebaugh]

We should emulate mapbox/mapbox-gl-js#1215 here for all the methods related to map view options. It would be nice if C++14 supported C99's designated initializers. In lieu of that we'll probably want to support a chaining syntax:

map.jumpTo(mbgl::ViewOptions().center({lat, lng}).zoom(4.2).bearing(45));

[1ec5]

How about a struct (call it Viewport or somesuch) that specifies center, zoom, and bearing (and someday pitch)? It would be analogous to the MGLCoordinateRegion or MGLMapCamera that we’ll need to address #1092 and #1643.

[1ec5]

It would be nice if C++14 supported C99's designated initializers.

Ah, using a struct would be less convenient in the absence of designated initializers or compound literals. clang++ supports both in C++14, but we’ve enabled pedantic warnings as errors, forbidding their use in this codebase.

[jfirebaugh]

A struct what I was implicitly going for with ViewOptions -- the question is what syntax is most convenient for setting some, but not all, of its members, where the unspecified members use the current map values.

[incanus]

Camera API is close to landing: #2193

[1ec5]

flyTo still needs to be implemented. jumpTo is implemented though.

[incanus]

Whoops, good catch.

[incanus]

Piggybacking off of @adam-mapbox's work in this branch in c788cea and some chat discussion, we might look into temporarily disabling compression in our SQLite caching backend to see if it helps with drawing after jumps. Profiling would probably be in order too, just to see what is the bottleneck (if possible).

[incanus]

That'd be around here and here.

[incanus]

Per some chat discussion, we could also look into loading 1/4 as many parent tiles or even 1/16 as many grandparent tiles for the destination as a way to quickly warm the cache so that something could be drawn closer to as soon as we land.

[jfirebaugh]

#3171