Create heatmap of points on xy plane in javascript

Question

I am looking for a way to dynamically plot points on an xy plane as a heatmap (to see the density of point distribution) in javascript.

Google Charts seems to have a pretty good tool for creating scatter plots which I created in a jsfiddle here: https://jsfiddle.net/bq8cds8d/, but I am not sure how to make it into a heatmap and couldn't find it anywhere on Google's website or documentation of the options object:

var options = {
 title: 'Age vs. Weight comparison',
 hAxis: {title: 'Age', minValue: 0, maxValue: 15},
 vAxis: {title: 'Weight', minValue: 0, maxValue: 15},
 legend: 'none'
 };

I also found the library heatmap.js here https://www.patrick-wied.at/static/heatmapjs/example-minimal-config.html, which offers the right heatmap functionality but I cannot figure out how to change the scales, so the data is not plotted correctly.

Any advice on getting google charts to make a heatmap or changing the scale on heatmap.js?