UPDATE ON JUL 2021: I am rewriting this web map application. The new version of this app is now in the following link.
https://github.com/KHwong12/viewshed-peaks
A web map application for investigating area visible from the peaks of Hong Kong
This web map stands out other web map in terms of:
- Compute visible area on map directly
- Check the location of the peaks
- No similar web application in Hong Kong
How much of the city you can see from the peaks?
This project is an interactive 3d web map for viewers to explore where they can see from the peaks of Hong Kong. The web map calculate the visible area (viewshed) from any point the user clicked on the map.
In addition, the user can select their own visible range when computing the viewshed so as to imitate the visible range during different weather. The current visibility are also available in the webpage for users' reference (data provided by API of Hong Kong Observatory).
Overview of the web map
Example usage of the map to drag and view the topography of the hill, as well as zoom to the designated spots
Example usage of performing a viewshed analysis, allowing users to view the visible area from the peaks
- Drag and wander around the 3D map and investigate the topography.
- Click on the peaks (or any other places you like). A red pin will appear on the place you clicked.
- The application will then compute the visible area (viewshed in jargon) from that point. The white grids appears on the map shows the area visible from the centre.
- Drag the slider to set your desired visibility (1-20km) to simulate how far you can see from the centre.
Known Issues:
- Attributes missing in some Peaks
- Problem of raw data downloaded from OpenStreetMap
- Viewshed cannot be executed
- Unknown error related to viewshed function in ArcGIS REST service. Tested with same query parameters could result in pass/fail at different times
- Further Investigation Required
TODO: Features to be Fixed/Changed/Added/Removed
TODO