I am looking for areas in a city that are suited for setting up precipitation measuring stations. One constraint is, that the station has to be distant from each object at least two times the object's height.

I have a raster (14000 x 11000 cells, 2 m resolution) representing the height above the ground of every object in the city (buildings, vegetation etc.). An Approach to buffer relevant pixels didn't lead to a result due to limited computation power. My first idea was to translate this distance into an angle (26.57 deg) and run an analysis, that's giving the maximum viewing angle to the sky. If it's higher than 26.57, the cell is not suited. But I haven't found a tool to calculate exactly this for every raster cell.

What tool or alternative solution can I use to find suitable areas? I am using ArcGIS.

  • You do not state which GIS system you are using?
    – Hornbydd
    May 21 '19 at 8:54
  • GIS SE uses a "Focused question/Best answer" model. Questions here should not only state the problem, but also show the work done towards solving the problem, with a detailed description of the error encountered. We also have a One question per Question policy, and listing four potential software environments effectively becomes four different questions. Please choose one environment and start framing the problem in that environment, so that we can get a better idea of what you have, and where you want to go.
    – Vince
    May 22 '19 at 1:57

Providing terrain is flat, compute buffers twice the size of your objects heights, and use them to erase your are of interest. What remains is your suitable part:

enter image description here

  • As my raster is quite big (14000 x 10000 cells) and most of the cells represent objects and therefore would have to be buffered, this solution consumes much computing power and crashes ArcGIS as well as QGIS on my computer.
    – felix
    May 22 '19 at 8:00
  • So your forest represented by separate trees? I used points as an example only, mate.
    – FelixIP
    May 22 '19 at 8:16

Not the answer you're looking for? Browse other questions tagged or ask your own question.