Implement data-driven styling for line-gradient

[herbetom]

User Story

I would like to style lines based on data.

Rationale

It's currently (as far as i can tell) not possible to define gradients based on values provided via geojson properties. This means all gradients of a layer are the same.

For example i've got a "Transmit Quality" value for two points (and many of them). I would like to draw a line between them and color it with a gradient according to the two values (for example red if the value is low, yellow if it's in the middle and green if it's high).

What i can do today is create a seperate layer for each possible gradient combination. But in my case that would mean creating hundreds of layers. Instead it would be nice to do some form of property lookup for the desired values and change the gradient within the layer.

[HarelM]

I believe this is possible now already with "line-progress", isn't it?

[herbetom]

From my understanding line-progress is an quite essential part of displaying gradients (which are supported) but then the gradient in itself is hardcoded and identical for the whole layer.

https://maplibre.org/maplibre-style-spec/layers/#line-gradient
maplibre/maplibre-style-spec#740

[HarelM]

Reading the user story again, I'm not sure I understand the ask... Can you please clarify it in the original post?

[herbetom]

done. Let me know if it's still unclear.

[HarelM]

Sorry, still not fully clear... Can you add a geojson example to showcase the input, with the current solution off multiple layers and the "wishfull" solution?