quadtile-index
v0.0.6
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Convert between x,y map tile coordinates and a bitwise-interleaved single integer
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quadtile-index
Convert between x,y map tile coordinates and a bitwise-interleaved single integer
Quadtiles use a 2-bit tile interleaved addresses. An x and y coordinate value bit representation of up to 26 bits each can be converted to a single integer value up to 56 bits. The limit is due to JavaScript's maximum lossless integer representation. For example, two 8 bit values xxxx xxxx and yyyy yyyy would produce a singel xyxyxyxy xyxyxyxy xyxyxyxy xyxyxyxy index value.
The library will assert the validity of each value, and allows optional zoom for additional verification.
For more info, see quadtile indexes info
xyToIndex(x, y, [zoom])
Convert x,y into a single integer with alternating bits
indexToXY(index, [zoom])
Convert index into the x,y coordinates (as a [x,y] array)
isValidCoordinate(val, [zoom]), isValidIndex(index, [zoom]), isValidZoom(zoom)
Boolean validation functions
maxZoom
Constant: Maximum supported zoom level (26)