41 lines
1.0 KiB
Plaintext
41 lines
1.0 KiB
Plaintext
function hexToBytes(hex) {
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const bytes = [];
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for (let c = 0; c < hex.length; c += 2) {
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bytes.push(Number.parseInt(hex.slice(c, c + 2), 16));
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}
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return new Uint8Array(bytes);
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}
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function bytesToFloat64(bytes, offset) {
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const buffer = new ArrayBuffer(8);
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const view = new DataView(buffer);
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for (let i = 0; i < 8; i++) {
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view.setUint8(i, bytes[offset + i]);
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}
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return view.getFloat64(0, true);
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}
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function parseEWKB(hex) {
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const bytes = hexToBytes(hex);
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let offset = 0;
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const byteOrder = bytes[offset];
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offset += 1;
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const view = new DataView(bytes.buffer);
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const geomType = view.getUint32(offset, byteOrder === 1);
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offset += 4;
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let _srid;
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if (geomType & 536870912) {
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_srid = view.getUint32(offset, byteOrder === 1);
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offset += 4;
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}
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if ((geomType & 65535) === 1) {
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const x = bytesToFloat64(bytes, offset);
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offset += 8;
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const y = bytesToFloat64(bytes, offset);
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offset += 8;
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return [x, y];
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}
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throw new Error("Unsupported geometry type");
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}
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export {
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parseEWKB
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};
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//# sourceMappingURL=utils.js.map |