Tooltip was originally inserted as a child element of svg/g which means it will never show (as it is not an svg element). Instead, append it directly to the body and then update on mouseover, rather than via mousemove - to make the code a bit more responsive and reduce the number of event calls and DOM updates.
Also clean up some of the code and use some CSS to simplify the d3 a little bit as well.
Tooltip was originally inserted as a child element of
svg/gwhich means it will never show (as it is not ansvgelement). Instead, append it directly to thebodyand then update on mouseover, rather than via mousemove - to make the code a bit more responsive and reduce the number of event calls and DOM updates.Also clean up some of the code and use some CSS to simplify the d3 a little bit as well.