This tool allows the user
to create, from a cadastral or thematic IL represented by
entities of the type point or polygon, another thematic,
cadastral or numeric IL, but with entities of type point.
Generating
sampling points from a thematic IL
-
activate in the "Control
Panel" a thematic category and
an associated IL that contains polygons or vector points. IL's
with a raster representation cannot be used, but if you wish, first
convert the matrix into a vector;
-
click on Tools
- Sampling Points Generation... in the
main menu. The
associated window will be displayed;
-
click on
Output
Category...to choose the category to which the output IL will belong.
The
window "Categories List" is presented. Choose a numeric
or thematic category and click on Apply in this window;
-
type in the name of the Output Layer to be created;
-
click
on
Apply.
IMPORTANT: The operation is performed over
the IL or Cadastral Map that is active in the "Control Panel".
NOTE: Note that the new IL should be
available in the "Control Panel". If the output category is of the
numeric model, the heights of the points will be the classes associated to
the polygons or thematic points.
Generating
sampling points from a cadastral IL
-
activate in the "Control Panel" a cadastral category and an associated IL that
contains polygons or vector points
-
click on Tools
- Sampling Points Generation... in the
main menu. The
associated window will be displayed;
-
click on Output
Category...to choose the category to which the output IL will belong.
The
window "Categories List" is presented. Choose a numeric,
thematic or cadastral category and click on Apply in this
window;
-
type in the name of the Output Layer to be created;
-
in case the output category is of the model
Numeric, select
from the list Category the desired object and select also,
from the list Attributes, that will be used as the value of the
height Z of the generated point;
-
click
on
Apply.
NOTE: Note that the new IL should be
available in the "Control Panel". If the output category is
of the model numeric, the heights of the points generated correspond to the
attributes of the selected object.
Generating Sampling
Points: Concepts
When the input IL
contains polygons you can opt to generate the points from he center of mass
of the polygons or from its centroid (the point
used to identify the object or class). The figure below shows an example of a
cadastral map with polygons where sampling points were generated from the
center of mass and also from the centroid.
Cadastral Polygons
, Points - center of mass
Points - centroid
The table below presents
the possible types for the generation of sampling points. In case the input
IL contains polygons you must opt to generate the points from the center of
mass or the centroid.
Input
|
Numeric (Output)
|
Thematic (Output)
|
Cadastral (Output)
|
Cadastral
Polygons
|
3D Points (choose the
center of mass or the centroid)
Suffix (_LAB)
* the
attribute of the object will be the height Z of the point.
* only
labeled polygons will be converted into points.
|
2D Points (choose the
center of mass or the centroid)
Suffix (_LAB)
* the
point will not be associated to any class.
* every
polygon (either labeled or not) will be converted into points. BUG1
|
2D Points (choose the
center of mass or the centroid)
Suffix (_LAB)
* the
points created will keep the association with the object.
* only
labeled polygons will be converted into points.
|
Cadastral
Points
|
3D Points (the
cadastral point itself will be a numeric)
Suffix (_P2D)
* the
object attribute will be the height Z of the point.
* only
labeled points will be converted into points.
|
Cannot do that
* you
can use the cadastral point itself for the analysis, without the need to
copy into thematic.
|
Cannot do that
* you
can use the cadastral point itself for the analysis.
|
Thematic
Polygons
|
3D Points (choose the
center of mass or the centroid)
Suffix (_LAB)
* the
code of the class will be the height Z of the point.
* every
polygon (associated or not with a class) will be converted into points. Polygons
that
are
not
associated
will
have
Z = 0.
|
2D Points (choose the
center of mass or the centroid)
Suffix (_LAB)
* every
polygon (associated or not with a class) will be converted into points.
|
Cannot do that
Cadastral categories
are not presented for this option.
|
Thematic
Points
|
3D Points (the
cadastral point itself will be a numeric)
Suffix (_P2D)
* the
code of the class will be the height Z of the point.
* every
point (associated or not with a class) will be converted into points.
* points
that are not associated will have Z=0 for the spot height.
|
Cannot do that
* you
can use the thematic point itself for the analysis, without the need
to copy into another thematic.
|
Cannot do that.
Cadastral categories
are not presented for this option.
|
|