Using QGIS and ThreeJS to display orthorectified UAV data

displaying ebee flight orthomosaic using QGIS and the excellent qgis2threejs plugin. The building is Culzean Castle in Ayrshire.

 

Flight data gathered by my colleague Paul at GeoGeo. The original grid resolution is 3cm / pixel. What you see here is a much lower resolution.

 

There's an online version here to play with. I'd recommend opening that in Chrome, threeJS is very memory intensive.

 

For this version, I used a combination of SAGA GIS and QGIS. SAGA for preprocessing, QGIS for rendering.

 

In SAGA,

 

- random sampled the XYZ file using Python (10% of points). The full point cloud was too big for this visualisation.

- generate a 0.3m raster from this sample XYZ

- fill the few blank pixels using 'fix single cell gaps'

- recalibrated altitude using grid calculus

- applied an analytical hillshade, using 'Raytrace' option

 

The rest was done in QGIS:-

 

- composited the layers (hillshade was 15% opaque, multiply)

- exported to web app with qgis2threejs

- you can use the "custom plane" option in the exported web page to experiment with rising sea levels. Tide goes in, tide goes out, tide goes in, tide goes out... :-)

Done