This project is read-only.

How to display a dem (raster GeoTIFF) ?

Dec 4, 2013 at 2:18 PM
Edited Dec 4, 2013 at 3:16 PM
I'm trying to display a dem raster in GeoTIFF format and I think that it is display as an image insted of a dem. Here are the default view in QGIS:

Image

And here the display with DotSpatial 1.4:

Image

I have the Application Extensions, the Plugins folder aded to my project and the AppManager. But GDAL doesn't seem to be loaded and I'm pretty sure that that is the cause of the problem.

Thanks
Dec 6, 2013 at 2:39 AM
Edited Mar 14, 2014 at 4:36 AM
Try:
  1. Make a directory name "Windows Extensions" And copy GDAL to the folder.
  2. Add "AppManager1.LoadExtensions()" in the Initial Form code as follow:
    Public Sub New()
      ' This call is required by the designer.
      InitializeComponent()
    
      ' Add any initialization after the InitializeComponent() call.
      AppManager1.LoadExtensions()
    End Sub
Dec 6, 2013 at 7:54 AM
beware that, as far as I know, dotspatial does not deal with multi band rasters hence you might experience some problem in visualizing geotiff files

Oscar
Dec 6, 2013 at 1:53 PM
The GeoTIFF contains only one band of float values (GDT_Float32). The AppManager constains two directories by default: Application Extensions and Plugins. I have try the Windows Extensions, but that didn't work. I have a "Raster Data Operations in DotSpatial" tutorial. But they talk about a "Data Extensions" directory that didn't exist. Any others idea?
Dec 6, 2013 at 3:45 PM
try using the identify tool to query the map in some points and see what values it gives. If it is a constant value then you are right, the problem might be that GDAL is not loaded, otherwise if the value at different points is different then it is just a matter of color scale.

Oscar
Dec 6, 2013 at 4:20 PM
It look like that GDAL is not loaded. The identify tool display info with a shapefile, but not with the geotiff.

shapefile
Image

geotiff
Image
Dec 9, 2013 at 4:17 AM
I tried to write a sample.
download and test please
http://www.mediafire.com/download/4478n6u044ook98/TstGDAL.rar
Hope it help
Dec 9, 2013 at 6:47 PM
Thanks !
Dec 10, 2013 at 8:50 AM
How is it now?
Can you load your DEM with the sample project?
Dec 10, 2013 at 3:53 PM
Yes I can load my raster now. Here's the dem with the network.

Image