KEYWORDS

       Anna Petrasova, NCSU GeoForALL Laboratory
       Tomas Zigo (standalone module)

RasterDigitizer is a simple tool to quickly draw lines, areas, and circles and save these features in a
       raster map. It is accessible from the Map Display toolbar (from the combo box on the right).

       RasterDigitizer currently allows you to:

           •   draw polygons, lines and points

           •   set category value of the feature you are drawing

           •   set feature width (width of currently digitized line or diameter of  a  digitized  point  in  map
               units)

           •   create a new raster from scratch or from an already existing raster

           •   undo edits and save edits before leaving the digitizer

       The typical workflow includes these steps:

       1      Set computational region as needed.

       2      Switch to Raster Digitizer and select a map to create.  Select either a new raster or create a new
              raster from existing raster, also select raster type (CELL, FCELL, DCELL)

       3      Specify category value and width before drawing a feature

       4      Specify digitizing tool (area, line, point)

       5      Start digitizing and when you want to finish area or line, userightclick6      Change color of temporary overlay depending on your needs

       7      Set different category and repeat

       8      At any point you can use Undo or Save9      If  existing  raster is used for the new raster, digitized areas will respect the color table, but
              you can always set different color table.

       In the following figures we start with elev_lid792_1m raster map in North  carolina  sample  dataset  and
       digitize  two  buildings,  one rectangular and one with circular footprint.  Both buildings have the roof
       level at 130 m. We set the width when digitizing the point to 50 meters which  results  in  the  building
       having  50  m in diameter.  When we are done with digitizing, we save the result and explore cast shadows
       of the buildings with r.sun module:
       g.region raster=elev_lid792_1m
       # now create elev_edited raster by digitizing and save
       r.slope.aspect elevation=elev_edited slope=elev_slope aspect=elev_aspect
       r.sun elevation=elev_edited aspect=elev_aspect slope=elev_slope beam_rad=beam day=172 time=6
       Figure:Stepstodigitizenewbuildingsonelev_lid792_1mrastermap.

       display, GUI, raster, editing, digitizer

       Raster Digitizer respects computational region including the currently set resolution.

wxGUI,wxGUIcomponents,r.in.poly(backendofdigitizer),g.gui.vdigit

       Available at: wxGUI Raster Digitizer source code (history)

       Accessed: Friday Apr 04 01:21:40 2025

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GRASS 8.4.1                                                                                 wxGUI.rdigit(1grass)