|
Steps - How to start? - Step 6
|
|
VISUALIZING OTHER
CATEGORIES
In this project that we
are studying there are other categories. Lets first consider Drainage
and Distances.
These categories have a
kind of data called thematic. These type of data has the ability to divide
the space into themes or classes. For instance, an "Uso do Solo"
map, divides the space represented in the map into themes, such as forest
agricultural areas, industrial areas, urban areas, or lakes. The data from
the "Drenagem" (Drainage) category have this same pattern
with just a small difference, not all areas are labeled, but only the ones we
are interested on, that is, Lakes and Rivers. All the other themes are set
aside, although they exist in the real world. The same method was used to
create the "Distancias" (Distancies) category, where only
some distance intervals were indicated. All the others were ignored, which
creates a generic theme called "background".
The following steps allow
to select and to visualize the Information Layers associated to these
categories.
VISUALIZING THEMATIC DATA
To Visualize the Thematic Drainage
Data :
-
click View in the main menu andselect Control Panel, or use the button
in the toolbar;
-
select the "Drenagem" (Drainage) category and the IL "Mapa Rios", select
the buttons Classes and Lines (see figure below);

-
click the Draw button
, so you can visualize the IL selected in main display, which is
currently active.
To visualize the
"Distancias" Thematic data:
-
keep the IL Mapa Rios
selected in the panel
-
select the "Distancias"
(Distances)
category and the IL "Mapa_dis_Drenagem", select the Classes and the Lines buttons (as it is shown in the IL above);
-
click the Draw button
to visualize both
selected ILs in main display.
NOTE: the IL "Mapa_dis_Drenagem" overlaps
the IL "Mapa Rios". This happens because it is required
to define the visualization priority;
-
activate the IL "Mapa_dist_Drenagem"
and change the Priority. An IL priority value less than
another means that one will be displayed first in the visualization
window;

-
click the Draw button
. Notice that the IL "Mapa_dist_Drenagem" is now
shown first over the IL "Mapa Rios".
NOTE: Although both ILs belong to the
same thematic model, the IL "Mapa Rios" was obtained by
manual digitalization from a topographic chart from this area, and the IL
"Mapa_dist_Drenagem" was obtained from a SPRING process.
-
unmark both IL selected for
visualization clicking twice over the categories "Drenagem"
and "Distancias", next another data model will be
presented.
VISUALIZING NUMERICAL
DATA
Data in this category
represents what is known as Digital Terrain Model (DTM). The numerical data
category, as designed in the SPRING system, allows association of a
numerical value for each point in the terrain considered. For instance:
altimetry associates height to each point in the terrain. We are constrained
to model just the topography, a numerical category can be used to describe
how acid is a soil by indicatng its "Ph" level for each
point in the terrain. Different forms of representation can be used in a
computer in order to represent a numerical category. It is possible to store
numerical data by: Sampling - values are obtained from points in the space or
from lines with the same values, Grid - a matriz representing points spread
uniformily in space, or TIN - a triangle network used to model a surface.
Lets test each one of
these representation forms.
Visualizing
the Digital Model Data:
-
click on View in the main
menu and enable the Control Panel, option or use the
button
in the toolbar, if the option is not visible in the
main menu.
-
select the "Altimetria" (Altimetry)
category and the IL "Mapa Altimetrico". Mark the
Samples check box (as shown in the figure below)

-
click the Drawing button
in the tools bar in the main menu to visualize the selected Plan
in display 1, which is activated.
-
deselect the Samples option by,
unchecking the Samples
check box.
-
check now the Grid check
box
-
click the Drawing button
-
deselect the Grid option.
-
select the TIN option
-
click the Drawing button

You have seen different
ways to visualize a numerical Information Layer (IL).
VISUALIZING DERIVATIVE
DATA
Numerical data can be
processed, and new derivative data can be obtained. In this data base we
generate a declive data and, starting from this plan we can generate a
declive thematic map indicating declive layers from the terrain. Depending on
these declive layers defined at the moment the thematic map was generated, it
is possible to define, for instance, adequated areas for construction and
other inadequate areas.
You can visualize the
existing decliving map after selecting it. The thematic maps can also be
respresented using several formats. When it is selected data from categories "Drenagem" (Drainage) and Rede_Viaria, we can see how to visualize data in
the vectorial form, produced from polygons, lines, and points. Now we will
see how to visualize stored data in a matrix form. In this case it will be
presented the indicator Raster
in the control panel. Both representation forms are equivalent and can be
used indistinctivelly to represent the thematic data. Selecting the best
representation will depend on the desired goal, so there is no
"best" representation without an aplication. The Spring System
allows storage of different representation forms for the same data. The
selection of one or other representation will be done depending on the
required efficiency related to data manipulation, precision, or even the
volume of storage data. In the first trial these details can be neglected.
Visualizing Derivative Data for a Digital Model:
-
click in View in the main
menu and enable the Control Panel, or use the button
in the toolbar, if the Control Panel is not visible.
-
select the Declividade
category and the IL Mapa_declividade.
-
select the Image button

-
click the Drawing button
to
visualize the required Plan in main display, which is activated.
Note: Thematic models map, like the
declive one, can have a legend associated to it, which facilitates the color
interpretation used in the map. Click in View - Legend ... in
the main menu and click the little triangle button to the left of the
IL (see figure below).

-
unselect all the ILs selected for
visualization with a double click over the corresponding categories,
because next it will be seen the cadastral data model.
OTHER
VISUALIZATION RESOURCES VISUALIZING CADASTRAL DATA
Topics
|