readme update

README.md

@@ -93,8 +93,9 @@ For Whitebox Tools not only the plugin needs to be installed but also the binari
 for the respective operating system:
 
 1) Download the binaries for your operating system [here](https://www.whiteboxgeo.com/download-whiteboxtools/).
-2) Unzip the downloaded folder and put it somewhere safe, e.g. C:/mywhiteboxfolder/
-3) In Qgis, go to Settings / Options.
+2) Unzip the downloaded folder and put it somewhere safe, e.g. C:/mywhiteboxfolder/   
+   > **!!! Important: Please make sure the path does not contain spaces or special characters**
+4) In Qgis, go to Settings / Options.
 
 <pre>
 <img src="src/help/wbt1.jpg" alt="Options" width="500"/>
@@ -120,7 +121,8 @@ Then, remove the existing WhiteboxTools plugin and re-install it following the a
 
 For LAStools not only the plugin needs to be installed but also the executables:
 
-1) Download the LAStools software from [here](https://rapidlasso.com/lastools/) and unzip it to a permanent location, e.g. "c:/LAStools"
+1) Download the LAStools software from [here](https://rapidlasso.com/lastools/) and unzip it to a permanent location, e.g. "c:/LAStools"  
+    > **!!! Important: Please make sure the path does not contain spaces or special characters**
 2) In Qgis, go to Settings / Options.
 
 <pre>
@@ -530,6 +532,74 @@ In that case you can rename the file avoiding special characters.
 <br>
 <br>
 <br>
+<pre>TypeError: Input parameters:
+
+{ 'CRS' : QgsCoordinateReferenceSystem('EPSG:4882'), 'GPD' : True, 'InputFilelaslaz' :'C:\\LiDAR\\PointCloud.laz', 'LAS' : 'TEMPORARY_OUTPUT', 'LVD' : True, 'LowNoise' : True, 'SetCellSize' : 0.5, 'VisualisationCM' : True, 'VisualisationDFM' : True, 'VisualisationDfME' : True, 'VisualisationHS' : True, 'VisualisationOPN' : True, 'VisualisationSVF' : True, 'VisualisationVAT' : True, 'classLas' : False, 'prefix' : '' }
+
+
+
+LAStools command line
+
+C:/Folder with spaces in path/LAStools\bin\lasground -v -i "C:\LiDAR\PointCloud.laz" -ignore_class 7 -city -ultra_fine -o "C:/Users/Username/AppData/Local/Temp/processing_EgHuxH/c7a29a19bf6c4b148513db3fac318057/lasground1.laz"
+
+LAStools console output
+
+'C:/Folder' is not recognized as an internal or external command, 
+
+operable program or batch file. 
+
+
+
+Results: {'': None}
+</pre>
+
+This error is caused if the folder of the LAStools binaries has spaces in its path. Please refer 
+to [LAStools installation instructions](#lastools) on how to install them properly.
+<br>
+<br>
+<br>
+<pre>WhiteboxTools command:
+
+"C:/folder with spaces/WBT/whitebox_tools.exe" -v --run=LidarPointDensity --input="C:\Users\Username\AppData\Local\Temp\processing_EgHuxH\3b285912c0f2479997199fcd54f724ea\lasheight.las" --returns="all" --resolution=2.0 --radius=10.0 --exclude_cls="0,1,3,4,5,7,8" --output="C:\Users\Korisnik\AppData\Local\Temp\processing_EgHuxH\35588cdbcec74ec793e018ece309f90f\gpd.tif"
+
+WhiteboxTools output:
+
+********************************
+
+* Welcome to LidarPointDensity *
+
+* Powered by WhiteboxTools *
+
+* www.whiteboxgeo.com *
+
+********************************
+
+thread 'main' panicked at 'The system cannot find the file specified. (os error 2)', whitebox-tools-app\src\main.rs:72:21
+
+note: run with `RUST_BACKTRACE=1` environment variable to display a backtrace
+
+Process returned error code 101
+
+Results: {'output': 'C:/Users/Username/AppData/Local/Temp/processing_EgHuxH/35588cdbcec74ec793e018ece309f90f/gpd.tif'}
+
+Unable to execute algorithm
+
+Could not load source layer for input: C:/Users/Username/AppData/Local/Temp/processing_EgHuxH/35588cdbcec74ec793e018ece309f90f/gpd.tif not found
+
+Unable to execute algorithm
+
+Could not load source layer for input: C:/Users/Username/AppData/Local/Temp/processing_EgHuxH/35588cdbcec74ec793e018ece309f90f/gpd.tif not found
+
+Execution failed after 0.48 seconds
+
+</pre>
+
+This error is caused if the folder of the Whitebox binaries has spaces in its path.
+Please refer to [Whitebox installation instructions](#whitebox-tools) on how 
+to install them properly.
+<br>
+<br>
+<br>
 <pre>TypeError: 'fileFilter' is an unknown keyword argument
 </pre>