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(11) 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, use v.db.addcol:
v.db.addcol testisola col="GRASSRGB varchar(11)"
To add/change a color, use v.db.update:
v.db.update testisola col=GRASSRGB val="123:45:237" where="cat=139"
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.
# display roads with category numbers: d.vect roads display=shape,cat lcolor=green # display randomly colorized soils map with attributes d.vect -c soils disp=attr attrcol=label # display randomly colorized selected vectors from soils map d.vect -c soils where="label='VBF'" display=shape,attr attrcol=label
3D points, 3D lines and 3D polygons colorized according to z height:
g.region rast=elevation.10m r.random elevation.10m n=5000 vector=random3d -d d.mon x0 # display as black points d.vect random3d # display 3D points colorized according to z height d.vect -z random3d zcol=gyr # 3D contour lines r.contour elevation.10m out=contour20m step=20 d.vect -z contour20m zcol=gyr # generate 3D triangles v.delaunay random3d out=random3d_del # display 3D polygons colorized according to z height d.vect -z random3d_del type=area zcol=gyr
Last changed: $Date$