Outils généraux¶

Rendu dépendant de l’échelle¶

Le rendu dépendant de l’échelle permet de spécifier des échelles minimale et maximale auxquelles la couche doit être visible. Pour définir une échelle de rendu, ouvrez la fenêtre de Propriétés en double-cliquant sur une couche dans la légende et dans l’onglet Général, cochez la case Visibilité dépendante de l’échelle puis saisissez les valeurs voulues.

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.

Contrôler le rendu¶

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 Définir le rayon de tolérance d’accrochage et de recherche). 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)

Sélectionner et désélectionner des entités¶

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 Expressions 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.

Grille¶

^Grille vous permet d’ajouter un graticule et des coordonnées à la carte.

Figure Decorations 1:

The Grid Dialog

1. Sélectionnez via le menu Vue ‣ Décorations ‣ Grille. La fenêtre s’affiche (voir figure_decorations_1).

2. Cochez la case Activer la grille et définissez les paramètres de la grille en fonction des couches chargées dans le canevas de carte.

3. Cochez la case Dessiner une annotation et définissez les propriétés de l’annotation en fonction des couches chargées dans le canevas de carte.

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

Étiquette de Copyright¶

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

Figure Decorations 2:

The Copyright Dialog

1. Sélectionnez via le menu Vue ‣ Décorations ‣ Étiquette de Copyright. La fenêtre s’affiche (voir figure_decorations_2).

2. Entrez le texte que vous souhaitez afficher sur la carte. Vous pouvez utiliser du code HTML comme le montre l’exemple.

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

4. Assurez-vous que la case Activer l’étiquette des droits d’auteur est cochée.

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.

Flèche du nord¶

^{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

Échelle graphique¶

^{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.

Pour ajouter une échelle graphique :

1. Sélectionnez le menu Vue ‣ Décorations ‣ Échelle graphique. Une fenêtre s’affiche (voir 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. Assurez-vous que la case Activer l’échelle graphique est cochée.

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

Annotations 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.

Annotations 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.

Formulaire d’annotation¶

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

Créer un signet¶

Pour créer un signet :

1. Déplacez-vous sur la zone concernée.

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

3. Entrez un nom pour décrire le signet (jusqu’à 255 caractères).

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

Notez que vous pouvez avoir plusieurs signets portant le même nom.

Travailler avec les signets¶

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.

Intégrer des couches¶

La fenêtre suivante vous permet d’intégrer des couches provenant d’autres projets QGIS :

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

Bien que les couches intégrées soient éditables, vous ne pouvez pas en modifier le style et l’étiquetage.

Supprimer des couches intégrées¶

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