leaflet-webgl-heatmap
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A Leaflet plugin for a popular WebGL Heatmap library.
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WebGL Heatmap
=============
webgl-heatmap.js is a JavaScript library for high performance heatmap display.
Demo
----
Live Demo at [codeflow.org](http://codeflow.org/entries/2013/feb/04/high-performance-js-heatmaps "")
How to use it
-------------
Instantiate a new heatmap, errors can be one of:
* Webgl is not supported
* No floating point texture support
* Floating point render target not supported
* Shader Compile Error: ...
* Shader Link Error: ...
```javascript
try{
var heatmap = createWebGLHeatmap({canvas: yourCanvas});
}
catch(error){
// handle the error
}
```
creation arguments
* canvas: the canvas you wish to draw on
* width: explicit width
* height: explicit height
* intensityToAlpha: defaults to true
* gradientTexture: texture used instead of color calculation, can be path or an image
Add a data point.
* x and y relative to the canvas in pixels
* size in pixels (radius)
* intensity between 0 and 1
```javascript
heatmap.addPoint(x, y, size, intensity);
```
Add a list of data points.
* x and y relative to the canvas in pixels
* size in pixels (radius)
* intensity between 0 and 1
```javascript
heatmap.addPoints([{x:x, y:y, size:size, intensity:intensity}]);
```
Draw queued data points:
```javascript
heatmap.update()
```
Display the heatmap
```javascript
heatmap.display()
```
Multiply all values in the heatmap by a number (useful for decay)
```javascript
heatmap.multiply(0.995)
```
Clamp all values in the heatmap to between two values:
```javascript
heatmap.clamp(0.0, 1.0)
```
Blur all values a little:
```javascript
heatmap.blur()
```
License
-------
Copyright (c) 2013, Florian Boesch <pyalot@gmail.com> http://codeflow.org/
WebGL Heatmap is licensed under any of the following licenses at your choosing:
* MIT: see mit-license
* GPL: see gplv*-license
* BSD: see bsd-license