Problem - We need to be able to return a raster cell value for a given latitude and longitude??
Background - We are currently evaluating ThinkGeo Mapsuite to use in a Land-use modelling environment, whereby we are running water-balance simulations (using CUDA) at defined gridpoints using a series of vector and raster layers as inputs to the models. We need to be able to query the raster layers to return cell values at the predefined grid point locations. Obviously this is easy to do for vector layers (although its a bit slow in the interregation), but we can't see how to do this for the raster layers. Currently our raster data is in the Erdas Image format using the FDO libraries, although we are likely to use other raster formats as well.
Possible Solutions - Here are the options:
- Use the current mapsuite tools to do this?? Is this possible?? I can't see that it is.
- Use the FDO or GDAL libraries to query the data - we will be looking into this next.
- Modify the mapsuite tools to achieve this - again - is this possible?
Coming from a modelling environment, this is an extremely important functionality to have in a GIS tool... I had just assumed that the ThinkGeo mapsuite would be able to do this, and was quite shocked to find that it doesn't seem to have the capability. Does anyone have any suggestions or advice?
Regards,
David McClymont
Principal Software Engineer
DHM Environmental Software Engineering Pty Ltd