Esri / wind-js

An demo animation of wind on a Canvas layer in the JSAPI
MIT License
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canvas cartography esri gfs-data javascript javascript-library visualization web-development wind

Wind-JS

Check out the live demo

Wind JS

This project is an experiment in client-side data processing and visualization. Most of the code in this project is taken from https://github.com/cambecc/earth and has been re-purposed to support easier application to a variety of mapping APIs and Frameworks.

How it works

The code for this project uses nothing but an HTML5 Canvas element and pure Javascript. The data come from the Global Forecast System which produces a large variety of datasets as continuous global gridded datasets (more info below). The data is passed into a JS class called Windy which takes the bounds of the map, the data, and the canvas element and then applies a Bilinear Interpolation to generate a smooth surface. Once the surface has been generated a function randomly places "particles" onto the canvas at random x/y points. Each particle is then "evolved", moving in a direction and at a velocity dictated by the interpolated surface.

The Data

Before GFS data can be used with this code it has to be converted into JSON. To do this we used another awesome project by @cambecc called grib2json. That tool converts data in the GRIB2 file format into a JSON structure with the grid represented as an array. An example result of that tool can be seen in the gfs.json file.

Resources

Issues

Find a bug or want to request a new feature? Please let us know by submitting an issue.

Contributing

Esri welcomes contributions from anyone and everyone. Please see our guidelines for contributing.

Credit

All the credit for this work goes to @cambecc for creating cambecc/earth. The majority of this code is directly taken from there, since it's utterly awesome.

Licensing

This project inherits an MIT license from cambecc/earth because 95% of the code here was copied from that project.

A copy of the license is available in the repository's license.txt file.