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copcesium wiki

CesiumJS provider for real-time COPC (Cloud Optimized Point Cloud) streaming and rendering.

This wiki is the in-depth companion to the README. The README covers install and quick start; the wiki covers how the internals work, how to tune them, and how to get out of trouble.

Pages

• Architecture — the three-layer pipeline (Data → Cache & Scheduler → Render) and how a node travels through it.
• Options & Tuning — every option, what it trades off, and how to tune for quality vs. memory vs. bandwidth.
• Coordinate Systems — WKT auto-detection, the proj4 fallback table, compound CRSes, and vertical units.
• Converting to COPC — turning LAS/LAZ into .copc.laz with PDAL, untwine, or QGIS.
• Troubleshooting — CORS, Range Requests, blank screens, misplaced clouds, and other common failures.
• Third-Party Licenses — what's bundled into the published package, and under which licenses.

At a glance

• Streaming, not loading — only the octree nodes the camera can see are fetched, over HTTP Range Requests.
• Off the main thread — LAZ decompression and coordinate transforms run in a pool of reused Web Workers.
• Screen-space-error LoD — point density matches what the camera can actually resolve, with no flash of empty space mid-transition.
• CRS-aware — auto-detects the source coordinate system from the file's own WKT metadata.
• Live-tunable — pixelSize, sseThreshold, and the whole styling API (colorMode, opacity, classificationFilter, intensityRange) can be adjusted on a running data source with no reload.
• Genuinely drop-in — a single self-contained .mjs; the Worker and its WASM are inlined at build time.

Links

• npm package
• Issue tracker
• Example viewer (basic)
• Example viewer (advanced, full sidebar UI)