35 lines
757 B
TypeScript
35 lines
757 B
TypeScript
import SphericalMercator from '@mapbox/sphericalmercator';
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import { BoundingBox, TileParams } from './types';
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const TILE_SIZE = 256;
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const mercator = new SphericalMercator({
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size: TILE_SIZE
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});
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function getBbox(z, x, y) {
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return mercator.bbox(x, y, z, false, '900913');
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}
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function getXYZ(bbox, z) {
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return mercator.xyz(bbox, z, false, '900913');
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}
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function formatParams({ tileset, z, x, y, scale }: TileParams): string {
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return `${tileset}/${z}/${x}/${y}@${scale}x`;
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}
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function isOutsideExtent({ x, y, z }: TileParams, bbox: BoundingBox) {
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const xy = getXYZ(bbox, z);
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return xy.minY > y || xy.maxY < y || xy.minX > x || xy.maxX < x;
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}
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export {
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TILE_SIZE,
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getBbox,
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getXYZ,
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formatParams,
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isOutsideExtent
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};
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