WS07: QGIS from vector to raster and back again
Trainers: Lene Fischer (University of Copenhagen)
Schedule: Monday Morning 9-13
The Scenario is autumn, storm and high tide. The area is a small village near the costline. The houses in the village are in risk of getting flooded.
With Free and Open Data from The Danish Geodata Agency, we will find the buildings in the risk zone for 2 different sealevels. How can we do this? At first we create an elevation model from the Pointcloud. For better visualizing we create a Hillshade and Colorize the Elevation modelmap. Viewing in web with QGIS2ThreeJS.
With the webmap we can see the sealevel increase and view the buildings. But it is only a view. To find the exact buildings we have to make calculations for a scenario with 2 different sea levels.
To find the buildings within the flooded area, we Convert the calculated Raster into Vector and perform a spatial query. The buildings are then categorized and colorized.
The flooded area calculated. Finally the map are presented in an Atlas and uploaded to the web.
- Create DEM with LAS2DEM
- Create Hillshade
- Colorize With Pseudocolor and Blending
- Visualize with QGIS2ThreeJS
- Convert raster to vector
- Spatial Query Select by Location
- Update attribute
- Categorize and Colorize
- Calculate area
- Create Vectorgrid
- Printcomposer with Atlas
- Upload to WEB
Tags: open data, QGIS