search

potree / PotreeConverter

Create multi res point cloud to use with potree
http://potree.org
BSD 2-Clause "Simplified" License
690 stars 427 forks source link

pointcloud georeference issue #542

Open d4nd1978 opened 2 years ago

d4nd1978 commented 2 years ago

Hello everyone,

I am trying to publish a LAS file on a map. I found these examples on https://github.com/potree/potree/ and what I need is as potree+cesium example. To do that I followed the descripted procedure: I converted my LAS file with potree-converter, copied the folder under potree-dev/pointcloud/ and copy an html from the example folder and link to my cloud.js file. My cloudpoint is displayed in Russia insted of Italy, is not georeferenced. I opened the LAS file with LASinfo and the coordinates seems:

number of point records: 4991131 number of points by return: 4991131 0 0 0 0 scale factor x y z: 0.01 0.01 0.01 offset x y z: 4600000 1100000 4100000 min x y z: 4670817.18 1194567.51 4161555.95 max x y z: 4671107.53 1194661.47 4161868.43 variable length header record 1 of 1: reserved 0 user ID 'LASF_Projection' record ID 34735 length after header 24 description 'by LAStools of rapidlasso GmbH' GeoKeyDirectoryTag version 1.1.0 number of keys 2 key 1024 tiff_tag_location 0 count 1 value_offset 3 - GTModelTypeGeoKey: ModelTypeGeocentric key 2048 tiff_tag_location 0 count 1 value_offset 4326 - GeographicTypeGeoKey: GCS_WGS_84 reporting minimum and maximum for all LAS point record entries ... X 7081718 7110753 Y 9456751 9466147 Z 6155595 6186843

Where am I wrong? Thanks for your help

arjan-kuiper commented 2 years ago

I believe the projection from the las file is not automatically copied to your cloud.js/metadata.json. This has to be done manually. See issue #174 and #544

If you're using EPSG:4326 you have to put +proj=longlat +datum=WGS84 +no_defs as your projection value.

yulan0215 commented 2 years ago

I believe the projection from the las file is not automatically copied to your cloud.js/metadata.json. This has to be done manually. See issue #174 and #544

If you're using EPSG:4326 you have to put +proj=longlat +datum=WGS84 +no_defs as your projection value.

Hi, I am sorry if I used EPSG: 5652, what should I input? Same? Thx

arjan-kuiper commented 2 years ago

I believe the projection from the las file is not automatically copied to your cloud.js/metadata.json. This has to be done manually. See issue #174 and #544 If you're using EPSG:4326 you have to put +proj=longlat +datum=WGS84 +no_defs as your projection value.

Hi, I am sorry if I used EPSG: 5652, what should I input? Same? Thx

It should be +proj=tmerc +lat_0=0 +lon_0=9 +k=0.9996 +x_0=32500000 +y_0=0 +ellps=GRS80 +towgs84=0,0,0,0,0,0,0 +units=m +no_defs

You can use EPSG.io to figure out what the correct projection is for the coordinate system that you are using.

gzotti commented 1 year ago

Thank you for this line! Not finding any docs, I had hoped it was as simple as "EPSG:5652".