@mapbox/geo-viewport/example/index.html

convert between viewports and extents

<img src="http://api.tiles.mapbox.com/v3/examples.map-zr0njcqy/-96.240234375,36.814089432555164,4/1000x800.png" /><img src="http://api.tiles.mapbox.com/v3/examples.map-zr0njcqy/-96.240234375,36.814089432555164,3/500x300.png" /><img src="http://api.tiles.mapbox.com/v3/examples.map-zr0njcqy/-96.240234375,36.814089432555164,2/200x100.png" /><img src="http://api.tiles.mapbox.com/v3/examples.map-zr0njcqy/-96.240234375,36.814089432555164,1/100x100.png" /><img src="http://api.tiles.mapbox.com/v3/examples.map-zr0njcqy/-96.240234375,36.814089432555164,0/10x10.png" /><img src="http://api.tiles.mapbox.com/v3/examples.map-zr0njcqy/13.9471435546875,37.46956723008272,8/1000x800.png" /><img src="http://api.tiles.mapbox.com/v3/examples.map-zr0njcqy/13.9471435546875,37.46956723008272,7/500x300.png" /><img src="http://api.tiles.mapbox.com/v3/examples.map-zr0njcqy/13.9471435546875,37.46956723008272,5/200x100.png" /><img src="http://api.tiles.mapbox.com/v3/examples.map-zr0njcqy/13.9471435546875,37.46956723008272,5/100x100.png" /><img src="http://api.tiles.mapbox.com/v3/examples.map-zr0njcqy/13.9471435546875,37.46956723008272,1/10x10.png" />