DESCRIPTION

d.vect displays GRASS vector data in the active frame on the graphics monitor.

NOTES

d.vect can simply be used typing d.vect map=vector_map. There are a large variety of optional parameters which allow the user to specify vector type, colors, data fields, SQL queries, label size and justification, etc.

By default d.vect fills in holes in polygons (islands). If you only want to show active areas limit the features with, e.g., "d.vect cats=1-999999".

In order to display attributes in the map, display=attr must be specified in addition to the column name (attrcol parameter).

Colors may be specified in an attribute table column named 'GRASSRGB' (which is a varchar column containing RRR:GGG:BBB values), see the flag -a.

A table for a vector map might look like this: 

  echo "select * from testisola" | db.select
  cat|label|GRASSRGB
  0|no data|255:255:255
  90|FRASSILONGO|23:245:67
  104|LEVICO|23:145:67
  139|PERGINE VALSUGANA|223:45:237
  168|SANT'ORSOLA|223:45:67
  190|TENNA|123:45:67

To add the GRASSRGB color column, the SQL alter function is used: 

  echo "ALTER TABLE testisola ADD COLUMN GRASSRGB varchar(11)" | db.execute

To add/change a color, the SQL update function is used: 

  echo "update testisola set GRASSRGB='123:45:237' where cat=139" | db.execute

A much simpler method of color coding is by using the -c flag which displays vector elements of like category number with a random color.

This module can use FreeType/TrueType fonts if they have already been selected with d.font.freetype.

EXAMPLES

d.vect map=vectmap display=shape,cat lcolor=green
d.vect map=markveggy.vegtype where="VEGTYPE = 'IFA'"
d.vect -c map=soils display=shape,attr attrcol=label

SEE ALSO

d.erase, d.what.vect, d.rast, d.font.freetype
GRASS SQL interface

AUTHOR

Radim Blazek, ITC-Irst, Trento, Italy

Last changed: $Date$