Enhancement Request: Streamline use of custom end-markers

[seemantk]

Hi @susielu! Thank you for creating d3-annotation, it's lovely.

I was curious about the arrowhead/circle options. It looks like the builder runs for every connector that has a marker.

Was wondering if you'd considered SVG's native marker element which knows how to attach itself to the end of a line, and so by default scales itself to the stroke-width and rotates itself to match the line.

Thus, the arrow marker paths would go into a <marker> element in <defs>, and get called using the marker-end attribute.

Sorry if you've already looked and discarded this.

[susielu]

Oh wow, that looks great. I didn't know of that element in SVG. I will take a look thanks @seemantk