fisheye magnifier with fixed focus

This time with a fixed, hard-coded focus

a further iteration on the block Fisheye Magnifying Glass from @micahstubbs

an iteration on @fernoftheandes‘s bl.ock Encircling D3’s Fisheye Distortion that uses ES2015 syntax

Original README.md

Except for the code segments that render the magnifying glass (as circle or path), this is essentially a copy of Mike Bostock’s Fisheye Distortion example.

The motivation for this was largely aesthetical but also a bit functional. When using the Fisheye as an aid to viewing large datasets, I often find myself experimenting with the degree and radius of the distortion. In such cases, I find it helpful to see the exact reach of the distortion and then decide the best configuration for a particular dataset.