Tips

• When you are drawing polygons, you can draw holes inside edited polygons by holding down Shift.

• You can copy the attribute table to a spreadsheet like Excel (or any program that accepts tab-delimited data). In the attribute window, press Ctrl+A to select all the rows, then press Ctrl+C to copy the data to the clipboard. You can then go to your spreadsheet program and paste in the data.

• If you have a layer containing a single feature that you want to use for the fence, simply rename the layer to "Fence".

• If you need to pan during drawing: 1) press and hold down the "Shift" and "Alt" keys, 2) pan, 3) release the keys, 4) go on drawing

• If you want to open ECW raster image, find on web ER Mapper ECW drivers (NcsCnet.dll, NCSEcw.dll and NCSUtil.dll) and copy them in Openjump/LIB/EXT folder. Those files can be find on ER Mapper web page as a part of Image Compression SDK. Read carefully the license details. This tip works only with Windows XP/9X. However another option is to register NCSUtil, NCSCnet, and NCSEcw with the PATH environment variable (Win32), or the LD_LIBRARY_PATH (Unix). The parameters of the virtual machine can specify their location too using the VM property:

-Djava.library.path=<path_to_ncs_libraries>. 

Alternatively, a file jncsclasses.properties in the user's home directory can specify the location.

• If you copy paste big layers, you will notice that it takes much memory. A full copy of the layer is made in the clipboard. Even if you remove the source layer and the copied layer, clipboard is still full of data. If you want to clear it, simply copy an empty layer. The previous one will be replaced by an empty dataset.