To manipulate an Information Layer

A set of objects which have basic common characteristics makes an Information Layer (IL). In a project each IL is associated to a Category and consequently it is referred to single data model (thematic, numeric, image, cadastral, or network). The IL representations are differentiated as a function of the data model they belong; for instance, an IL of the numeric category can have as representations: samples (points and lines), regular grid, triangular grid (TIN) or contour lines.

An IL has to belong to a single category and, thus, to a single data model; it has to have an bounding box less or equal to the project bounding box, and has to have a scale (for the thematic, cadastral and network categories) and spatial pixel size (for numeric and image category) compatible with the data.

The options for an IL manipulation are:

 

Each Information Layer can have different representations, depending on the model to which it belongs. Next the possible representations and the code used in the "Control Panel" (see about IL's visualization) are presented:

THEMATIC

Points (P) - show all 2D points; Lines (L) - show all lines defining a polygon or not; Matrix (M) - vectors formatted as a matrix; Classes (C) - presents points/lines/polygons that are associated to classes, with its corresponding visual aspects; Text (T) - toponimy automatically generated or edited.

NUMERIC

Samples (A) - spot heights and imported contour lines or edited; Grid (G) - rectangular grid; TIN (Ti) - triangular grid "Triangular Irregular Network"; Contour Lines (I) - contour lines generated from a grid; Image (Im) - gray level image of the grid; Text (T) - toponimy automatically generated or edited.

IMAGE

M (M) - monochromatic channel, R (R) - red channel, G (G) - green channel, B (B) - blue channel; Text (T) - edited toponimy over the image; Synthetic (S) - three band coding into a single image; Classified (C) - image created by a classification process; Labeled (R) - lines created by image segmentation.

NETWORK

Lines (L) - show all lines; Objects (O) - show lines/nodes that are associated to objects, with its corresponding visual aspects; Text (T) - toponimy automatically generated or edited.

CADASTRAL

Points (P) - show all 2D points; Lines (L) - show all lines defining a polygon or not; Objects (O) - presents points/lines/polygons that are associated to the objects, with the corresponding visual aspects; Text (T) - toponimy automatically generated or edited.


See below how to create, change and remove an information layer.


See also:
SPRING Conceptual Model
Modeling Processes


Creating an Information Layer

In order to create an IL do not forget that the database has to have a category corresponding to the model where the IL will be created. In case the procedure to create an IL while importing a data is used or when executing a LEGAL program, it is required also to define a category in the active database.


Creating an Information Layer:

  • click on Edit - Infolayer... in the main menu or in , to open the "Infolayer" window;
  • select in the Category list, the category that will be used to create an information layer. Notice that in the Model field the model associated to a category is presented;
  • type the Information Layer name. The IL name can have at most 32 characters , including blank spaces.
  • click on Bounding Box... if the IL has an area smaller than the project. Attention, because the default option is to use the same area of the active IL ( see details about how to handle this window);
  • click on Apply to confirm the new coordinates;
  • in Scale: type a value (for instance : 100000 - without a decimal point or a blank space). Only for the information layer of the thematic, cadastral and networks categories. The scale value will be useful mainly when the lines simplification function is used (see details about simplification) in or during the continuous mode digitization (see editing details);
  • Pixel Size: has to be provided for the information layer of the numeric, thematic, and image categories to specify the grid cell size in meters;
  • click on Create after providing all the required information.


NOTE: When the "Information Layer" window is opened, the active IL will be available in this window for any action about the IL; for instance, remove the IL. In case the user try to create an IL without changing the corresponding field, it will be informed that the IL already exists, requesting the removal of the representations of this layer.


NOTICE: click on Representations... to verify the information related to the selected information layer (active). When an IL is created, because there is no data, no representation will be available.


NOTICE: Click on Visual... to change the visualization characteristics of the active IL. Each IL can have different visualization characteristics for the points, lines, grids, sample, contour lines and labeled images entities. Changing the IL visual aspects allow that its entities can be seen with different colors, even if there is no association to classes or objects.
For example, it is possible to change the visual aspects of lines of a labeled image from a segmentation resulting process, or the number size in a rectangular grid, or even, the size and color of the associated texts in an IL.

HINT: For samples of the numeric model (contour lines) can be useful that each contour line is presented using a different color. This facilitates the error identification in the contour line height. This resource depends on the IL scale to generate the colors range, and, to enable it, the visual aspects has to be changed to the EMPTY type.

See also:
How to create a Project.
How to create a Database.

Information Layer Manipulation


Changing an Information Layer

The option to change an IL will allow the user to redefine the IL name, the pixel size and the scale.

  • Change the name is allowed to any data model, as far as it is not of the same category as the project. Different categories in the same project can have ILs with the same name.
  • Change the pixel size of the ILs numeric, thematic or image model is allowed, only if there is no data associated, that is, a grid, matrix or image respectively.
  • Change the scale is allowed for all categories that work with vector data, but the category for the image model.

NOTICE: Remember that when changing a scale in an IL, the parameters used for lines simplification or digitization will be changing too.

The table below presents the changing possibilities for name, pixel size or scale, as a function of the data model

 

Name

Pixel Size (meters)

Scale

Thematic

YES

YES (if there is no matrix associated yet)

YES

Numerical

YES

YES (if there is no grid associated yet)

YES

Image

YES

YES (if there is no image associated yet)

NO

Cadastral

YES

NO

YES

Networks

YES

NO

YES


Changing an Information Layer:

  • active an IL in the "Control Panel" ;
  • click on Edit - Infolayer... in the main menu or ;
  • change the active IL name, pixel size and/or scale, depending on the permissions presented in the table above;
  • click on Change to make the changes.


NOTE: Remember that any change in this window, it will always be executed on the active IL in the "Control Panel".


See also:
How to change a Project.

Information Layer Manipulation.


Activating an Information Layer

Activating an IL means that this IL will be available for any operation through the main menu. An active IL does not need, necessarily, to be visible in a drawing area.

Activating an Information Layer:

  • click on the Category list and next on the Infolayer in the "Control Panel";
  • notice that the name of the active IL is presented in the footnote in the main window and also in the "Infolayer" window with the respective representations already created.


See also:
How to activate a Project.
How to activate a Database.

Information Layer Manipulation.


Removing an Information Layer

Removing an IL means to erase all or some of the available representations in the information layer. The system allows to delete only the vector representation of a thematic IL, for instance. WARNING- As a "default" it will be eliminated all the representations, if a specific representation is not informed.

Depending on the model that the IL belongs to, there are the following representations to select:

  • * IL for the thematic category: Matrix, Vector and Text.
  • * IL for the image category: Matrix and Text.
  • * IL for the cadastral or network category: Vector and Text.
  • * IL for the numeric category: Samples (contour lines and points), Grid, TIN, Contour Lines (resulting from the grid interpolation) and Text.


Removing an IL:

  • active an IL in the "Control Panel" atalho_painel.gif - 967 Bytes;
  • click on Edit - Infolayer... in the main menu or atalho_pi.gif - 949 Bytes;
  • click on Remove to remove the information layer and all its representation of the active project, or selecting one of the representations before removing it.


NOTE: If the IL is unique for a given category, the IL name and corresponding category will disappear from the "Control Panel". However, the category will be kept in its active Database.



See also:
How to remove a Project.
How to remove a Database.

Information Layer Manipulation