GRASSラスター、ベクターレイヤをロードする

Loading GRASS raster and vector layers

With the GRASS plugin, you can load vector or raster layers using the appropriate button on the toolbar menu. As an example we use the QGIS alaska dataset (see Section #label_sampledata). It includes a small sample GRASS LOCATION with 3 vector layers and 1 raster elevation map. <P>

1. Create a new folder grassdata, download the QGIS alaska dataset qgis_sample_data.zip from http://download.osgeo.org/qgis/data/ and unzip the file into grassdata.
2. Start QGIS.
3. If not already done in a previous QGIS session, load the GRASS plugin clicking on Plugins > Manage Plugins and selecting GRASS. The GRASS toolbar appears on the toolbar menu.
4. In the GRASS toolbar, click the grass_open_mapsetOpen mapset icon to bring up the MAPSET wizard.
5. For Gisdbase browse and select or enter the path to the newly created folder grassdata.
6. You should now be able to select the LOCATION alaska and the MAPSET demo.
7. Click OK. Notice that some previously disabled tools in the GRASS toolbar are now enabled.
8. Click on grass_add_rasterAdd GRASS raster layer, choose the map name gtopo30 and click OK. The elevation layer will be visualized.
9. Click on grass_add_vectorAdd GRASS vector layer, choose the map name alaska and click OK. The alaska boundary vector layer will be overlayed on top of the gtopo30 map. You can now adapt the layer properties as described in chapter #sec:vectorprops, e.g. change opacity, fill and outline color.
10. Also load the other two vector layers rivers and airports and adapt their properties.

<P> As you see, it is very simple to load GRASS raster and vector layers in QGIS. See following Sections for editing GRASS data and creating a new LOCATION. More sample GRASS LOCATIONs are available at the GRASS website at http://grass.osgeo.org/download/data.php .

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