Using Line-Gradient Property

[riastrad]

When mapbox/mapbox-gl-native#12575 lands, a new example that demonstrates how to leverage this feature will be very helpful.

Especially as this delivers the ability to implement frequently asked for line animations.

[1ec5]

Note that the line-gradient property, like all the data-driven properties, lacks support for transitions: mapbox/mapbox-navigation-ios#1307 (comment). So animating a gradient will require changing the property on each frame on a timer.

[JanC]

Hi @riastrad, is your WIP example somehow working? I'm getting the exception

'NSInvalidArgumentException', reason: 'Invalid property value: [2][1]: Unknown variable "lineProgress". Make sure "lineProgress" has been bound in an enclosing "let" expression before using it.'

update: I've just found this issue mapbox/mapbox-gl-native#12917

[riastrad]

@JanC That's correct, while building out that example I ran into the issue you've linked to. I'm currently troubleshooting possible workarounds, but will likely hold off on finalizing until that issue is resolved.

[riastrad]

Just want to note that $lineProgress is an expression variable as of mapbox/mapbox-gl-native#13192, so we should be good to rebase on master and pick this back up (since the examples were bumped to v4.6.0 here: #244)

[captainbarbosa]

We should still do this!

[jumbopilot]

Hi guys, yes, would be very much appreciated.