[FOSS4G 2016] Point Clouds

Transcript

1. Potree Point Clouds in the Browser with WebGL Daniel Kastl / Markus Schütz - FOSS4G 2016
2. About me Geographer, Mapper, Software Developer Maintainer of the pgRouting Project Founder of Georepublic Living in Germany and Japan Enjoy Open Source FOSS4G and OSM Working with Point Clouds 2
3. What do we do with Point Clouds? 3
8. You can create your own Point Cloud? 8
13. 13 1.2 GB LAS file ~45 Mio. points
14. 14 How do we show mBillions of Points?
15. • A WebGL point cloud viewer for large datasets. • An Open Source project developed by Markus Schütz (and growing number of contributors) • Financially supported by Rapidlasso, Georepublic and others Potree 15
17. • Only a small part of data is essential for a given point of view • A multi-resolution Octree allows to quickly cull away unnecessary data and only load what is needed. 17 How does Potree work?
18. • Low-level nodes contain low resolution models of large areas • Resolution increases while coverage decreases at higher levels • Works similar to map tiling 18 How does Potree work?
19. • Each Octree node stored in a separate file • Server is only necessary as file store • No server side application required 19 How does Potree work?
20. Potree Javascript Library • Data conversion with the PotreeConverter • Uses Three.js rendering engine and inherits its capabilities • Client-side LAS and LAZ support from Plas.io • API for (measurement) tools • Open Source license (BSD) 20
21. Data format (PotreeConverter) • Input: ◦ las, laz and ply files • Output: ◦ Cloud.js file for metadata (BBOX, spacing, storage format) ◦ Octree nodes (las, laz or bin format) with position, color, intensity and classification information ◦ hrc files for the Octree hierarchy 21
22. Features at a Glance • Rendering billions of points in web browsers • Adaptive point size - adjust point size to reduce holes • Eye-Dome-Lighting (EDL) - illumination without normals • Renders RGB, elevation, intensity, classification, etc. • High-quality rendering modes (interpolation & splats) • Distance and area measurements, height profiles • Clipping volumes 22
23. “Beautiful Point Clouds” • Interpolation and high-quality splats ◦ Increase readability of fine details ◦ Avoid overlapping points through nearest-neighbor like interpolation or by blending overlapping points together 23
24. “Beautiful Point Clouds” • Eye-Dome-Lighting (EDL) ◦ Illumination without normals ◦ Outlines enhance depth-perception ◦ Especially useful to render elevation, classification or single-color 24
25. Annotations • Click annotation to zoom to points of interest 25
26. Height Profiles • 3D with multiple segments • Unrolled 2D view (With thanks to SITN) • Moving profile vertices updates 2D view on the fly 26
27. Measurement Panel • List of all measurements • Displays coordinates, distances, point colors, etc • Remove unwanted measurements • Adjust height profile width and open 2D profile 27
28. 28 http://potree.org/demo/potree_foss4g_bonn2016/examples/retz.html
29. 29 http://potree.org/demo/potree_foss4g_bonn2016/examples/retz.html
30. Examples http://potree.org/wp/demo 30
31. Limitations • Browser security policies require to run Potree from a web-server. • Requires WebGL capable browsers and devices • Only for viewing and analyzing, not manipulation of data. 31
32. Who is using Potree? • Various Companies and Institutions • As well as researchers, students, digital heritage, ... 32
33. More Projects • Entwine (Point cloud indexing for massive datasets) • Greyhound (Data streaming and serving environment for PDAL) • iTowns project (3D WebGL geospatial visualization) • 3D-Tiles (Specification for streaming massive heterogeneous 3D geospatial datasets) • pgPointcloud (PostgreSQL extension for point cloud data) 33
34. Standards … because they make Open Source stronger. 34
35. Version 1.4RC released - What comes next? • Potree 1.4, End of 2016 ◦ Faster Conversion ◦ Improved File Format (50% less space, fewer files) ◦ Greyhound/Entwine support (implemented by Hobu & NLeSC) • Afterwards ◦ Projecting maps onto point clouds in real time ◦ Load and display point cloud formats without conversion ◦ Virtual Reality, Tools, Analysis, ... 35
36. A lot more is possible and funding will help to make it happen! 36
37. Interested in Potree? Project: http://www.potree.org Email: daniel@georepublic.de, mschuetz@potree.org Twitter: @dkastl, @m_schuetz Thank you! 37