Vector color on a vector map
At this time, in a vector map, all de vectors have the same color. If the direction of the vectors can be classified, we can assign a color to each class and each vector in the class will have the same color. In this way, trend zones (identified by color) will be formed, if they exist.
We need to be able to define, for each vector, its personal color.
It's already possible to define color for each vetor, see a simple demo: https://jsfiddle.net/BlackLabel/borpwsuy/
What's more, you can use ColorAxis module to automatically colorize vectors according to some other value, for example direction: https://jsfiddle.net/BlackLabel/fwmhydjv/