Eliminate the syntactic distinction between "paint" and "layout" properties

[lucaswoj]

From @lucaswoj on December 23, 2016 14:34

The differences between "paint", "layout", and "top-level" properties are becoming increasingly nuanced. Without a firm knowledge of our implementation, it can be hard to reason about the behaviour of paint properties vs layout properties, especially in the context of data-driven styling. It is worth considering eliminating the syntactic distinction between "paint" and "layout" properties (as Studio does), instead providing documentation about the behaviour of each property.

Copied from original issue: mapbox/mapbox-gl-style-spec#635

[lucaswoj]

From @nickidlugash on January 25, 2017 20:54

This sounds good generally, but just want to flag that it may make the definition of a ref sound more convoluted.

[lucaswoj]

@nickidlugash We're getting rid of refs too 😄 As of now, ref is a no-op in GL JS.

[stevage]

Any more thoughts about this? I just implemented this in http://npmjs.com/package/mapbox-gl-utils and dear god it makes life simpler. You don't realise how much brainspace is spent trying to understand and remember why line-width and circle-radius are paint properties, but icon-size and text-size are layout properties.

[stevage]

Also, just wanted to comment on this:

Without a firm knowledge of our implementation, it can be hard to reason about the behaviour of paint properties vs layout properties, especially in the context of data-driven styling.

I have been using Mapbox-GL-JS a long time, and made many, many maps with it. I have absolutely no idea what the behaviour difference between paint properties and layout properties is. :) So, removing the syntactic requirement, and also documenting whatever that difference is on a per-property basis is a double-win for me.