NAME

       d.rast.edit  - Interactively edit cell values in a raster map.

KEYWORDS

       display, raster

SYNOPSIS

       d.rast.edit
       d.rast.edit help
       d.rast.edit  input=name  output=name  [aspect=name]   [width=integer]   [height=integer]   [size=integer]
       [rows=integer]   [cols=integer]   [--overwrite]  [--verbose]  [--quiet]

   Flags:
       --overwrite
           Allow output files to overwrite existing files

       --verbose
           Verbose module output

       --quiet
           Quiet module output

   Parameters:
       input=name
           Name of input raster map

       output=name
           Name for output raster map

       aspect=name
           Name of aspect raster map

       width=integer
           Width of display canvas
           Default: 640

       height=integer
           Height of display canvas
           Default: 480

       size=integer
           Minimum size of each cell
           Default: 12

       rows=integer
           Maximum number of rows to load
           Default: 100

       cols=integer
           Maximum number of columns to load
           Default: 100

DESCRIPTION

       The d.rast.edit program allows users to interactively edit cell category values in  a  raster  map  layer
       displayed to the graphics monitor using a mouse cursor.

USAGE

   Overview window
       An  overview  window  shows the entire map with a box showing the current editing region. The edit window
       shows the cells within the selected area.  Click on a new spot on the overview window to move the editing
       area.  Moving the editing view can take a while.

   Mouse and menus
       Cell editing is done using a mouse cursor to choose menu selections and indicate areas on  the  displayed
       raster map that are to be edited.

       Selections available at the top of the edit window are Save and Exit.

       As  the mouse travels over the cells in the edit window you are shown the current coordinates and current
       cell values under the cursor.

       To change the value of a cell put the new value to use in the "New value" box at the bottom left  of  the
       edit window under the coordinate information bar. A value of "*" indicates a NULL value should be used.

   Arrows
       This  function  is  available  for  users editing aspect maps.  The d.rast.arrow program is called, which
       draws arrows over the displayed cells to indicate the downslope direction of the cell.  You can  set  the
       aspect  map  to  use  on  the command line.  Aspect maps are expected to be in regular "GRASS" format, as
       produced by r.slope.aspect; i.e. degrees counter-clockwise from east.

NOTES

       There is no "undo" command or way to exit edit mode without saving changes.

       Any MASK in place will be respected when writing the new raster map layer, including  any  edits  to  the
       MASKed areas.

   Geographic Region Concerns
       d.rast.edit  reads  the  region  definition  for the raster map layer being edited from its internal cell
       header file. The new, edited copy of the raster layer will be created with the same resolution and region
       dimensions.

       The primary bane of the d.rast.edit program involves large map layers with  lots  of  rows  and  columns)
       and/or  slow  computers,  since the program must read and write raster map layers row by row for the full
       size of the map layer as dictated by its region size and resolution.  (The  current  region  settings  of
       north, south, east, and west will not limit the size of the edited copy of the map layer, since by use of
       the overview selection these values may change several times during the editing session).

TODO

       It  would be nice to incorporate a scrollable version of d.legend (such that one could see a label legend
       for files with many categories on a standard size sub-frame).  It would be  even  nicer  to  be  able  to
       select the category values from a graphical legend when editing cell values (thereby saving a trip to the
       text frame to type in the new value).

       Perhaps  method(s)  for  multiple   or  mass cell edits would be useful.  This could be done by providing
       modes in which the user may:
       1) edit a block of cells to a given value by drawing a box;
       2) be able to choose a given value which is automatically used as the new value on each cell chosen until
       a different value is desired.

       There is no interrupt handling.  This could leave files in .tmp or (rarely) result in  half-baked  raster
       maps.   The original file would survive unscathed by an interrupt at most any point in execution.  Beware
       of exiting the program by means other than using exit on the Main Menu.

SEE ALSO

        d.rast.arrow, d.rast.num

AUTHOR

       Tcl/Tk version: Glynn Clements
       Replaces Xdriver version in C by Chris Rewerts, Agricultural Engineering, Purdue University

       Last changed: $Date: 2011-11-08 03:29:50 -0800 (Tue, 08 Nov 2011) $

       Full index

       © 2003-2013 GRASS Development Team

GRASS 6.4.3                                                                                  d.rast.edit(1grass)