snap-points-2d

snap round 2d points

Usage no npm install needed!

<script type="module">
  import snapPoints2d from 'https://cdn.skypack.dev/snap-points-2d';
</script>

README

snap-points-2d

Runs iterative snap rounding on a set of 2D coordinates to produce a hierarchical level of detail for optimizing online rendering of huge 2D plots.

Install

npm i snap-points-2d

API

{levels, ids, weights, points} = require('snap-points-2d')(points, bounds?)

Reorders the points hierarchically such that those which are drawn at the same pixel coordinate are grouped together.

Inputs
  • points is an input array of 2*n coordinate values. It is kept untouched.
  • bounds is an optional array of 4 bounding box values of the points.
Outputs
  • points is an output float64 array with reordered an normalized to bounds point values.
  • ids is an output uint32 array which gets the reordered index of the points.
  • weights is an output uint32 array of point weights (number of points at the same pixel), which can be used for transparent rendering.
  • levels is an array of LOD scales. Each record is an object with the following properties:
    • pixelSize the pixel size of this level of detail in data units
    • offset the offset of this lod within the output array
    • count the number of items in the lod

License

(c) 2015 Mikola Lysenko. MIT License