LiDAR DATA! It's the universal format for 3D point cloud data!

<html>
<head>
  <title>LAS File Parser xbdev.net</title>
</head>
<body>
  <h1>LAS File Parser</h1>
  <input type="file" id="fileInput" />
  <button id="parseButton">Parse LAS File</button>
  <pre id="output"></pre>

  <script>
    document.getElementById('parseButton').addEventListener('click', () => {
      const fileInput = document.getElementById('fileInput');
      if (fileInput.files.length === 0) {
        alert('Please select a LAS file.');
        return;
      }

      const file = fileInput.files[0];
      parseLasFile(file);
    });

    async function parseLasFile(file) {
      const arrayBuffer = await file.arrayBuffer();
      const buffer = new DataView(arrayBuffer);

      // Extract header information
      const header = {};
      header.fileSignature = String.fromCharCode(...new Uint8Array(arrayBuffer.slice(0, 4)));
      if (header.fileSignature !== 'LASF') {
        alert('Not a valid LAS file.');
        return;
      }
      header.versionMajor = buffer.getUint8(24);
      header.versionMinor = buffer.getUint8(25);
      header.pointDataOffset = buffer.getUint32(96, true);
      header.numberOfPointRecords = buffer.getUint32(107, true);
      header.pointDataRecordFormat = buffer.getUint8(104);
      header.pointDataRecordLength = buffer.getUint16(105, true);
      header.xScaleFactor = buffer.getFloat64(131, true);
      header.yScaleFactor = buffer.getFloat64(139, true);
      header.zScaleFactor = buffer.getFloat64(147, true);
      header.xOffset = buffer.getFloat64(155, true);
      header.yOffset = buffer.getFloat64(163, true);
      header.zOffset = buffer.getFloat64(171, true);

      console.log('Header:', header);

      const points = [];

      // Read point data
      const pointDataStart = header.pointDataOffset;
      for (let i = 0; i < header.numberOfPointRecords; i++) {
        const offset = pointDataStart + i * header.pointDataRecordLength;

        const xRaw = buffer.getInt32(offset, true);
        const yRaw = buffer.getInt32(offset + 4, true);
        const zRaw = buffer.getInt32(offset + 8, true);

        const x = xRaw * header.xScaleFactor + header.xOffset;
        const y = yRaw * header.yScaleFactor + header.yOffset;
        const z = zRaw * header.zScaleFactor + header.zOffset;

        if (i < 10) { // Only log the first 10 points to avoid excessive logging
          console.log(`Point ${i}: raw(${xRaw}, ${yRaw}, ${zRaw}) -> scaled(${x}, ${y}, ${z})`);
        }

        points.push({ x, y, z });
      }

      displayPoints(points);
    }

    function displayPoints(points) {
      const outputElement = document.getElementById('output');
      outputElement.textContent = JSON.stringify(points, null, 2);
    }
  </script>
</body>
</html>

log:["Header:",{"fileSignature":"LASF","versionMajor":1,"versionMinor":2,"pointDataOffset":331,"numberOfPointRecords":21932,
"pointDataRecordFormat":0,"pointDataRecordLength":20,"xScaleFactor":0.01,"yScaleFactor":0.01,"zScaleFactor":0.001,
"xOffset":2000000,"yOffset":200000,"zOffset":0}]
log:["Point 0: raw(23084422, 5208093, -26) -> scaled(2230844.22, 252080.93, -0.026000000000000002)"]
log:["Point 1: raw(23081793, 5208206, 226) -> scaled(2230817.93, 252082.06, 0.226)"]
log:["Point 2: raw(23084437, 5208092, 204) -> scaled(2230844.37, 252080.91999999998, 0.20400000000000001)"]
log:["Point 3: raw(23105369, 5207193, 1613) -> scaled(2231053.69, 252071.93, 1.613)"]
log:["Point 4: raw(23104803, 5207218, 1493) -> scaled(2231048.03, 252072.18, 1.493)"]
log:["Point 5: raw(23104880, 5207214, 1673) -> scaled(2231048.8, 252072.14, 1.673)"]
log:["Point 6: raw(23094007, 5207681, 74) -> scaled(2230940.07, 252076.81, 0.074)"]
log:["Point 7: raw(23079978, 5208284, 88) -> scaled(2230799.78, 252082.84, 0.088)"]
log:["Point 8: raw(23074573, 5208528, -37) -> scaled(2230745.73, 252085.28, -0.037)"]
log:["Point 9: raw(23107424, 5207117, 2261) -> scaled(2231074.24, 252071.16999999998, 2.261)"]
...

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