This page presents the
procedures for Vector Edition or Topological
Edition. Thus, the same toolbar is used to edit ILs of the Thematic,
Cadastral, Network or Numerical model, diverging only in some small details.
Basically the user is able
to:
See first the editing tools
for each data model.
Other Options: Update Indexes and Update
Area/Perimeter.
NOTE: Thematic and cadastral maps
will be presented together, because editing them is basically the same
operation, with a small difference in the entities association (classes
for thematic maps and objects for cadastral maps). Later, it will be
presented how to edit networks and DTM maps.
See about
Digitalization using the SPRING
See
also:
The SPRING Conceptual Model
About Vector Edition
How to calibrate the digitizing table
About the vector elements
ASCII-SPRING format
The figure below presents the Vector
Edition toolbar.
Caption:
1) Type Button (Graphical Edition or Verify);
2) Contour Button;
3) Adjusted Nodes Button;
4) Not Adjusted Nodes Button;
5) Edition Button
(Lines or Points);
6) Edition Properties Button (Mode, Topology, Digit. Step and Tolerance);
7) Create Button;
8) Edit Button;
9) Remove Button;
10) Contour Curves Button;
11) Add Turn Restriction Button;
12) Remove Turn Restriction Button;
13) Tools Button; 14) Update Button;
15) Undo Button; 16) Save Button; 17) Show/Hide the Toolbar of Vector Edition Operations Button; 18) Exit Vector Edition Button; 19) Help Vector Edition Button. For a faster access to the Vector Edition Operations (as, for
instance, Add Point, Move Point, Move Area and Remove Point) it has also been created a toolbar
compounded by these operations. Caption: 1) Create Line Button; 2) Create Closed Line Button; 3) Create Circle Button; 4) Create Rectangle Button; 5) Add Point to a line Button; 6) Move Line Button; 7) Move Area Button; 8) Move Point of a line Button; 9) Break Line Button; 10) Join Line Button; 11) Concatenate Line Button; 12) Concatenate Area Button;
13) Change Orientation Button; 14) Properties of a line Button; 15) Remove Line Button; 16) Remove Area Button; 17) Remove Point of a
line Button; 18) Create Point Button; 19) Move Point Button; 20) Remove Point Button; 21) Adjust Button; 22) Generate Polygons Button. A thematic or cadastral map
has regions geographically defined by entities: points, lines and polygons.
The digitalization process in both cases is the same; the only difference is in
the application of each entity. A thematic map usually has
qualitative information about a unique theme, such as, vegetation classes, soil
etc. These data are obtained from field measures and later added in the system
either using Digitalization or from automatic image classification. A thematic map has to be
associated to a thematic model category, where the spatial modeling process is
defined by geo-fields, represented by homogeneous delimited areas (polygons),
polygonal lines or points. Each Geo-field is associated to a single spatial
variable value, that is, in a soil map, each point in the map is associated to
a specific soil type (e.g. Dusk Red Latosol). A cadastral map helps
getting information such as urban cadastral data, rural cadastral data etc.
This map has to be associated to a cadastral model category, where the spatial
model process is defined by geographical objects. The difference for a thematic
map is related to the fact that it does not have themes and considers its
elements as geographical objects with attributes, and can be represented in
several maps using different scales or projections. For instance, the lots in a
city are elements in the geographical space with several attributes (owner,
address, tax etc.) and they can be represented in several maps each using a
different scale. In the cadastral map, the
objects are usually defined a priori and its geographical location can be done
a posteriori. For example, it is possible to mention the objects "S�o Jos�
dos Campos Schools", and, more specifically, the "XXY High Scholl".
Such objects exist independently of their map representation; they are usually
created from their attributes and they will be located in space only in the
next step. Another example is the
object class hospital in a cadastral map, which can be a public or private hospital.
The hospital class attributes are inherited by the sub-classes public hospital
and private hospital, which might have their own attributes. Notes about thematic
and cadastral maps: A thematic map can be
stored in the vector or raster form (all entities are divided into cells of a
fixed size, and each cell has a corresponding value related to the most
frequent theme in that spatial location). However, in a cadastral map we have
only a vector representation. A topological representation
for thematic or cadastral maps, in the vector format has the type edge-node-region.
Edges are connected among themselves through nodes (starting and ending points)
so they make polygons (regions), or the edges only represent polygonal lines and
the points only geographical features which can not be represented in their
dimension. The line Digitalization
happens when the user wants to have an IL with vector elements in the form of
lines and/or polygons. If the lines don't define a polygon, it is neither
required the polygonalization nor the automatic adjustment, if the lines
extremes do not demand the connection. See next the procedure for
editing a thematic or cadastral map. NOTE 1: During a line editing (edge),
small circles (red) will be displayed around each point in the line. The size of
these circles depends on the value selected for the Digit. Step.
For a line previously created it is also possible to see its points, just
clicking on it using the mouse RB. NOTE 2: During the line editing as
"default", the green color (for the Continuous Mode) and red color (for the Step Mode) will be used until the end of the editing process, then
the line will turn red. Next, see the procedure to
change or fix the lines of a Thematic or
Cadastral Map. All edited lines will be
displayed using the red color. In order to store them and their changes in the
SPRING vector structure one needs to click on the "Save" button. Then, the lines
will be displayed using the color defined in the IL visualization aspects. NOTE
1: After
saving the lines it is not possible to use the "Undo" operation. Editing thematic and
cadastral points is useful for features representation or for objects that can
not be represented by polygons. In the same way as lines, points can be edited
using a digitizer table or a mouse. Remember that, in order to use a digitizer
table it is first required to calibrate it. The figure below shows two
points with different symbolism, one thematic (left) and another cadastral
(right). In the thematic case, it is only required that the point exists in
order to associate it with a class previously defined. However, if the point is
cadastral it is required to select an existing object and associate it using a
label and a name defined by the user. Details about the association with
objects or classes can be found here. As when dealing with lines,
points will exist in the SPRING vector structure after clicking on the "Save" button.
Once the points are saved it is not possible to Undo operation. NOTE: The edited points are displayed as
red circles. After saving
them, they are displayed using the
color and style defined in the IL visualization,
depending on the category they belong. During the geographical
entities Digitalization in a map, it is possible to change the visual aspects
of lines and points being edited. NOTE: The procedure to change the
entities visual aspects can also be obtained at Edit - Information Layer
in the menu, or using the Adjusting the nodes will
guarantee that they will be placed at the ending points of lines. The algorithm
uses a precision defined by the user, which corresponds to a distance
value centered at each node. If there is another node inside the square area
defined by the precision, they will be adjusted into a single node. This
procedure is valid for all nodes. The higher the precision,
the smaller the error possibilities and the smaller the possibility to mix up
neighbor nodes. The user should use the highest precision and, if required,
adjust other points using the manual adjustment procedure (Join Lines) using the Edit Button, or go to the Join Lines Button using the Operations toolbar. Depending on the precision
being used, some nodes, at the line ending points, may disappear, because there
will be only one node inside the square area defined by the precision. The
figure below shows what happens with the nodes at the ending points of a line. The figure below shows four
lines (1 through 4) when, after executing the adjustment procedure using
a certain precision value, one can observe that the adjustment procedure was
not enough to adjust the node in line 3. The "A" node, after
the adjustment procedure, has only the lines 1, 2 and 4. If possible and desirable one
can try a new node adjustment using a smaller precision. ATTENTION: Be careful when making adjustments
with smaller precision values, because some connections might change the line
pattern. For instance, in the figure above, the union of line 3 with the others
might not be desirable. Another example (figure
below) shows a common error performed by the user while digitizing several
islands, for instance: a cadastral map showing urban lots. Note what might
happen when using a small precision during the node adjustment. When closing
two or more islands, their shapes might change. During the lines edition
step, or lines correction for closing polygons, the user might click on the Adjusted
Nodes or Not Adjusted Nodes
button in the "Topology Editor" toolbar. After activating this
option click on Execute - Draw or click on the NOTA: There is also the option to
display the active IL Contour; just check the Contour button at the
toolbar. Once all nodes were
adjusted, the final topology must be defined through the polygonalization
procedure. The lines, which were considered as single structures so far, will
be considered as part of polygons, with a neighborhood relationship among them. The polygonalization option
assumes that the nodes were previously adjusted so, later on, polygon
identification can be performed with either as thematic classes or as cadastral
objects. ATTENTION: It only makes sense to generate
polygons when the map has entities of the polygon type. After defining the polygons
they can be associated to thematic classes, previously defined in the Database,
or they can be associated to cadastral objects. See how to proceed in both
cases. This is a map that uses the
arc-node topology and that stores the location and the symbolization
which is associated to structures linearly connected. The networks graphical
information is stored using only vector coordinates. A network map can be
associated to information of the following types: This map allows generating
a continuous cartographic base from information distributed in several maps.
The networks (electrical, telephone, water, sewerage etc) are interconnected in
a grid system, so that it is possible to make analysis and data simulations. This map must be associated
to the network model category, similarly to the cadastral model, where the
spatial modeling process is defined by geographical objects. Each geographical
object in the network map (e.g. telephone cables, water tubes, electrical
network transformer) has an exact geographical location and it is always
associated to descriptive attributes stored in the Database. The arc attributes
indicate the flow direction while the node attributes indicate the
impedance (path cost). The network topology forms a graph which stores
information about resources that flow among distinct geographical locations.
The topology is created automatically, that is, during the lines crossing, the
nodes are created automatically, thus the node adjust operation is not
required. Example given, consider an electrical network which has the following
components: poles, transformers, substations, transmission lines and keys. The transition lines are represented topologically as arcs in an
oriented graph, all other information are stored in their nodes. The figure below shows a
small part of a city streets network. Note that each segment is connected to a
node (green circle). It will be seen that one can associate objects either to
network segment or to nodes. The
editing tools such as Mode ( Continuous or Step), Topology (Manual or Automatic), Digit.
Step Note 1: During a line editing (arc), small circles (red) will be
displayed around each point in the line. The size of these circles depends on
the value selected for the Digital Step. For a line previously created it is
also possible to see its points, just clicking on it using the mouse RB. Note 2: During the line editing as "default", the green color (for the
continuous mode) and red color (for the step mode) will be used until the end
of the editing process, then the line will turn red. Note 3: Note that the Gener. Polygons button will be
disabled while working with a network maps. Only the Adjust will
be available for the IL. Next, see the procedure to change or fix a line in a network map. All edited lines will be displayed using the red color. In order to store them
and their changes in the SPRING vector structure one needs to click on the "Save"
button. Then, the lines will be displayed using the color defined in the IL
visualization aspects. Note 1: After saving
the lines it is not possible to use the "Undo" operation; In order to have a complete network map after importing lines or digitizing
them, one has to:
The digital terrain model is a mathematical representation for the spatial
distribution of a certain characteristic attached to a real surface. In order
to get this representation it is required to perform a line and points
Digitalization, which will make the samples so, later on, it will be possible
to generate interpolations (grids) and get products, such as 3D visualizations,
profile etc. During the lines Digitalization the cursor follows the contours, opened or
closed, defined in the map. The user associates a value for the z coordinate
(height) to a line. Another line type that can be digitalized are the break lines. The break lines
are used for triangular grid generation by quantum interpolation. These lines
can be referred to surface discontinuities, represented by valleys alignment or
ridges. For instance, a river can be edited as a break line where through the
shore lines there is a relief discontinuity without a height value associated
to it. These break lines can be considered or not during the triangular grid
generation. See more information about the break
lines and
triangular grids. During the points Digitalization the digitizer cursor is manually applied to the
point, and its coordinates (x, y) are registered. The user associates a value
for the z coordinate (height) to the point. A DTM map has to be associated to a numerical model category, where the spatial
modeling process is defined by geo-fields, thus, considering a certain
geographical area, a numerical Geo-field associates, to each point in space, a
real value. A DTM map can be stored either using the vector format (when there is a
representation referred to the samples or triangular grid) or raster format
(when there is a regular grid). In the vector representation, the topology can use the arc-node format, where
arcs are connected using nodes (starting and ending points) or Triangular Grid
(TIN). In this last case, the arcs are connected using points, making a
triangular grid. The raster representation uses a rectangular grid type, that is, an area will be
divided into fixed size cells, where each cell will have a value according to
the sampled data and the interpolation method used. For more details see
DTM data types and
interpolation methods. The figure below shows part of some samples, contour lines plus spot heights.
Note that both entities have to be in the same IL in order to consider them for
the interpolation process. Next, see the procedure for numerical map edition. The editing tools, such as Mode (Continuous or Step), Manual Topology
(The Automatic is not used for this kind of data), Digital Step and all Editing
options for lines and points, are the same as the ones described for cadastral
and thematic maps, one only needs to inform the Z value before starting
the Digitalization. NOTES: HINT: For
numerical models (contour lines) samples, it might be useful that each contour
line is displayed using a different color. This facilitates height errors
identification. This resource depends on the IL scale that will generate the
color variation and also to turn it on one should change the area visualization
aspects to the EMPTY type, from the "Information Layer"
window. Next, see the procedure for changing or fixing lines in a numerical map. The edited lines are presented in the red color. In order to store them in the
SPRING vector structure one have to click on the "Save"
button. The lines will be displayed using the color defined in the
visualization aspects of the IL. Note 1: After saving
the lines it is not possible to use the "Undo" operation. Editing break lines is performed in the same way as contour line edition, the
only difference is that there is no Z value for the break lines. Usually these
lines are used as mountain ridges or the bottom part of valleys
See details about using break lines. The spot heights should be in the same IL as the lines, so the system can
recognize them when using the interpolators. In the same way as the contour
lines, the spot heights can be edited using a digitizer or a mouse. If one
wants to use a digitizer to enter the points don't forget the digitizer
calibration. In the same way as lines, points will be stored in the SPRING vector structure
once the
"Save"
button was clicked on. After saving them it is not possible to use the "Undo"
operation. Note: The edited points are presented using red circles, after
saving them, they are
displayed using the
color defined in the IL
visualization aspects depending on the category they belong to. During a map digitizing process, the way contour lines and points are presented
can be changed. See next how to do it. HINT: For
numerical model (contour lines) samples it might be useful to show each contour
line using a different color. This helps error identification in the contour
line heights. This resource depends on the IL scale for generating a color
scale, in order to enable it, one should change the area visualization aspects
to the EMPTY type. A node adjustment guarantees that nodes at the end of contour lines will
coincide. The algorithm for node adjustment uses a precision defined by the
user, which corresponds to a distance value centered in each node. If another
node is placed inside the squared area defined by the precision factor, it will
be adjusted and the two nodes will become only one. The process is repeated for
all nodes. NOTE: Be careful when defining the precision value so contour lines with
different Z values will not get connected. The higher the precision the smaller
the possibility for errors and the higher the possibility to not connect all
the neighbor nodes. We suggest that the user sets a high precision value, and
if there are points not adjusted automatically then perform a manual adjust (
Join Lines) using the line editing option. During the line editing phase, or possible edge corrections which were not
closed into polygons, the user can select Show Nodes option in the "Topology
Editor" window. After activating this option click on Execute -
Draw or NOTES:
This task allows to get information related to the digitized data. Depending on
the model of the active IL we have:
For thematic or cadastral IL's the following data can be verified
at the bottom of the window:
Next the procedure for any kind of data verification is presented. NOTE: In case we are dealing with polygons, when clicking on them in the
active window, a green square highlights the polygon with a number, as
presented in the figure below. Update Indexes: This button was created in order to fix some inconsistencies
during the digitizing process. It is not known, for sure, but when using the
digitizing operations very often in the same section the line indexes file can
break in the existing IL. In this case, some lines already created just
disappear from the drawing window, although they are stored in the system.
Thus, in case this happens, just click on this button, so the system will fix
these inconsistencies.
Raster Edition
Thematic/Cadastral
Maps
Thematic Maps
Cadastral Maps
Line Digitalization
The figure below presents some lines that don't define a polygon and other
lines that define two polygons. The lines not defining a polygon (at left)
represent a river network, but note that the L1 line is not necessarily
segmented at the extremity of line L3. The crossing of these two lines is only
visual. However, the right part of the figure presents two polygons and the
line L2 is common to both polygons. To build this figure at right (the
polygons) it is required to edit the lines, adjust the extremities and make the
polygons. But the lines at left don't require any adjustment or
polygonalization.�Lines Digitalization in a
Thematic or Cadastral Map:
in the �Control Panel�, or click with the
mouse right button on the IL you wish to use. A dialog box will appear,
select Vector Edition;
in the main menu. In this case only the
digitizer cursor will be active;
Fixing Lines in a Thematic or Cadastral Map:
in the Control
Panel or click with the mouse right button on the IL you wish to
use. A dialog box will appear, select Vector
Edition. You can also click on the Edit menu and on Vector
Edition... to edit any active IL;
Points Digitalization
�Digitizing Points in Thematic
or Cadastral Maps:
in
the Control Panel or click
with the mouse right button on the IL you wish to use. A dialog box will
appear, select Vector Edition. You
can also click on the Edit menu
and on Vector Edition... to
edit any active IL;
n the main menu. At this
point only the digitizer cursor will be active;
�Removing Points in Thematic or Cadastral Maps:
�in the main menu. At this point only the
digitizer cursor will be active;
�Moving Points in Thematic or Cadastral Maps:
n the main menu. At this
point only the digitizer cursor will be active;
�Saving Points
The IL Visual Aspects
Changing the visual aspects
of lines and points in the active IL:
�in the active window to see the
changes.
�icon.
Adjusting Nodes
in
the active window which shows the edited lines. At the lines ending points
(nodes) a cross (X) will be displayed using the blue color if the line is not
connected to another line, and a green square when the node is connecting at
least two lines, that is, adjust of two or more lines
was correctly performed.
Generating
Polygons
�Adjusting and generating
polygons in a thematic or cadastral map:
Entity
Identification (labeling)
Network
Map
Network Maps - Lines Digitalization:
in the main menu. At this
moment only the digitizer cursor will be available;
Fixing Lines in a Network Map:
Saving lines
DTM
Sample Digitalization
Contour lines Digitalization
Contour lines Digitalization:
in the main menu. In this case
only the digitizer cursor will be active;
Fixing Lines in a Numerical Map:
Saving Contour lines
Break Lines Digitalization
Spot Heights Digitalization
Digitizing Spot Heights:
in the main menu. At this
moment on only the digitizer cursor will be enable;
Deleting Points from a Numerical Map:
in the main menu. At this
point only the digitizer cursor will be enable;
Moving Points in a Numerical Map:
in the main menu. At this
point only the digitizer cursor will be enable;
Saving Spot Heights
IL Visualization Aspects
Changing Categories Visual Aspects:
in the
active window to see the changes.
Node Adjustment
in
the active window which has the edited arcs. At the ending point of each arc
(node) a blue star (X) will be displayed when the arc is not connected to
another arc, and a green circle will be displayed if there is a connection
involving at least two arcs.
in the
active window.
Verification
For numerical and network IL's besides the information displayed
at the bottom of the window, other windows are also presented.
Verifying Data in an Active IL:
Other Window Options "Topology Editor"
Update Area/Perimeter : Object maps store the area and the
perimeter values (for cadastral models) and just the perimeter value (for
networks) in the Database. When using some of the digitizing tools
(operations), for instance, moving a point from a polygon limiting line, may
cause a change in the area and/or perimeter value. In this case the user has
two options: it is possible to adjust the line and polygon to fix the
area/perimeter value or just click this button. It is only required to adjust
lines and generate polygons again for the whole IL if the whole IL topology was
changed or broken, or when new polygons were created.
See also:
About Vector Edition
How to calibrate a digitizer
About the ASCII-SPRING format for vector elements