Ferramentas Gerais¶

Escala dependente da renderização¶

A representação dependente da escala, permite especificar as escalas mínima e máxima as quais a camada será visível. Para definir uma visualização dependente da escala, abra o diálogo Propriedades, clicando duas vezes sobre a legenda da camada. Na aba Geral, clique na caixa Visibilidade dependente da Escala para ativar a função, depois coloque os valores de escala mínimo e máximo.

You can determine the scale values by first zooming to the level you want to use and noting the scale value in the QGIS status bar.

Controlando a renderização do mapa¶

Map rendering can be controlled in the various ways, as described below.

Measure length, areas and angles¶

^{Measure Line}: QGIS is able to measure real distances between given points according to a defined ellipsoid. To configure this, choose menu option Settings ‣ Options, click on the Map tools tab and select the appropriate ellipsoid. There, you can also define a rubberband color and your preferred measurement units (meters or feet) and angle units (degrees, radians and gon). The tool then allows you to click points on the map. Each segment length, as well as the total, shows up in the measure window. To stop measuring, click your right mouse button. Note that you can interactively change the measurement units in the measurement dialog. It overrides the Preferred measurement units in the options. There is an info section in the dialog that shows which CRS settings are being used during measurement calculations.

Figure Measure 1:

Measure Distance (Gnome)

^{Measure Area}: Areas can also be measured. In the measure window, the accumulated area size appears. In addition, the measuring tool will snap to the currently selected layer, provided that layer has its snapping tolerance set (see section Configurando a Tolerância de Atracção e Raio de Pesquisa). So, if you want to measure exactly along a line feature, or around a polygon feature, first set its snapping tolerance, then select the layer. Now, when using the measuring tools, each mouse click (within the tolerance setting) will snap to that layer.

Figure Measure 2:

Measure Area (Gnome)

^{Measure Angle}: You can also measure angles. The cursor becomes cross-shaped. Click to draw the first segment of the angle you wish to measure, then move the cursor to draw the desired angle. The measure is displayed in a pop-up dialog.

Figure Measure 3:

Measure Angle (Gnome)

Selecionar e desselecionar feições¶

The QGIS toolbar provides several tools to select features in the map canvas. To select one or several features, just click on and select your tool:

• ^{Select Single Feature}
• ^{Select Features by Rectangle}
• ^{Select Features by Polygon}
• ^{Select Features by Freehand}
• ^{Select Features by Radius}

To deselect all selected features click on ^{Deselect features from all layers}.

^{Select feature using an expression} allow user to select feature using expression dialog. See Expressões chapter for some example.

Users can save features selection into a New Memory Vector Layer or a New Vector Layer using Edit ‣ Paste Feature as ... and choose the mode you want.

Malha¶

^Grid allows you to add a coordinate grid and coordinate annotations to the map canvas.

Figure Decorations 1:

The Grid Dialog

1. Selecionar do menu Ver ‣ Decorações ‣ Malha. O diálogo abre (veja figure_decorations_1).

2. Marque a guia Abilitar Malha e coloque as definições da malha de acordo as camadas carregadas na tela do mapa.

3. Marque a guia Desenhar anotações e coloque as definições de anotações, de acordo as camadas carregadas na tela do mapa.

4. Click [Apply] to verify that it looks as expected.
5. Click [OK] to close the dialog.

Rótulo Copyright¶

^{Copyright label} adds a copyright label using the text you prefer to the map.

Figure Decorations 2:

The Copyright Dialog

1. Selecionar no menu Ver ‣ Decorações ‣ Etiqueta de Propriedade Intelectual. O diálogo abre (veja figure_decorations_2).

2. Entre o texto que deseja colocar no mapa. Pode usar HTML como mostrado no exemplo.

3. Choose the placement of the label from the Placement combo box.

4. Confirme que a caixa Abilitar Etiqueta Direito de Cópia está selecionada.

5. Click [OK].

In the example above, which is the default, QGIS places a copyright symbol followed by the date in the lower right-hand corner of the map canvas.

Seta Norte¶

^{North Arrow} places a simple north arrow on the map canvas. At present, there is only one style available. You can adjust the angle of the arrow or let QGIS set the direction automatically. If you choose to let QGIS determine the direction, it makes its best guess as to how the arrow should be oriented. For placement of the arrow, you have four options, corresponding to the four corners of the map canvas.

Figure Decorations 3:

The North Arrow Dialog

Barra de Escala¶

^{Scale Bar} adds a simple scale bar to the map canvas. You can control the style and placement, as well as the labeling of the bar.

Figure Decorations 4:

The Scale Bar Dialog

QGIS only supports displaying the scale in the same units as your map frame. So if the units of your layers are in meters, you can’t create a scale bar in feet. Likewise, if you are using decimal degrees, you can’t create a scale bar to display distance in meters.

Para adicionar uma barra de escala:

1. Seleccione a partir do menu: menuselection: Ver -> Decorações -> Barra de Escala. O diálogo abre (veja figure_decorations_4).

2. Choose the placement from the Placement combo box.
3. Choose the style from the Scale bar style combo box.
4. Select the color for the bar Color of bar or use the default black color.
5. Set the size of the bar and its label Size of bar .

6. Confirme que a caixa Abilitar barra escala, está clicada.

7. Optionally, check Automatically snap to round number on resize.
8. Click [OK].

Anotações HTML¶

The ^{Html Annotation} tools in the attribute toolbar provides the possibility to place the content of an html file in a balloon on the QGIS map canvas. Using the Html Annotation tool, click into the map canvas and add the path to the html file into the dialog.

Anotações SVG¶

The ^{SVG Annotation} tool in the attribute toolbar provides the possibility to place an SVG symbol in a balloon on the QGIS map canvas. Using the SVG Annotation tool, click into the map canvas and add the path to the SVG file into the dialog.

Anotação de formulário¶

Additionally, you can also create your own annotation forms. The ^{Form Annotation} tool is useful to display attributes of a vector layer in a customized Qt Designer form (see figure_custom_annotation). This is similar to the designer forms for the Identify features tool, but displayed in an annotation item. Also see this video https://www.youtube.com/watch?v=0pDBuSbQ02o from Tim Sutton for more information.

Figure annotation 2:

Customized qt designer annotation form

Novo Favorito¶

Para criar um novo favorito:

1. Zoom ou pan na área de interesse.

2. Select the menu option View ‣ New Bookmark or press Ctrl-B.

3. Adicione um nome descritivo para o favorito (no máximo 255 caracteres).

4. Press Enter to add the bookmark or [Delete] to remove the bookmark.

Note que você pode ter vários favoritos com o mesmo nome.

Trabalhando com favoritos¶

To use or manage bookmarks, select the menu option View ‣ Show Bookmarks. The Geospatial Bookmarks dialog allows you to zoom to or delete a bookmark. You cannot edit the bookmark name or coordinates.

Zooming to a Bookmark¶

From the Geospatial Bookmarks dialog, select the desired bookmark by clicking on it, then click [Zoom To]. You can also zoom to a bookmark by double-clicking on it.

Deleting a Bookmark¶

To delete a bookmark from the Geospatial Bookmarks dialog, click on it, then click [Delete]. Confirm your choice by clicking [Yes], or cancel the delete by clicking [No].

Import or export a bookmark¶

To share or transfer your bookmarks between computers you can use the Share pull down menu in the Geospatial Bookmarks dialog.

Incorporando camadas¶

Os siguientes diálogos permitem incorporar camadas de outros projetos. Aqui um pequeno exemplo:

1. Press to look for another project from the Alaska dataset.
2. Select the project file grassland. You can see the content of the project (see figure_embed_dialog).
3. Press Ctrl and click on the layers grassland and regions. Press [OK]. The selected layers are embedded in the map legend and the map view now.

Figure Nesting 1:

Select layers and groups to embed

Enquanto as camadas incorporadas são editáveis, não podem ser mudadas suas propriedades de estilo e rotulação.

Removendo camadas incorporadas¶

Right-click on the embedded layer and choose ^Remove.