OK, next, labeling. Labeling seems to be undergoing some changes in QuantumGIS at the moment so there are two different labeling subsystems.
The first is under the layer properties as a tab. Turn on the labelling with the check box and select an attribute to use. You can also set a "buffer" around the text to make it more visible, adjust the positioning, and so on.
The newer system uses the labeling toolbar. Pick the label tool ("ABC" on top of a blue line)
This new tool uses a more advanced layout system that tries to position the label intelligently and with consideration to of the shape of the feature and the presence of other labels, both on the same layer and on other layers. You can pick a specific layout strategy and indicate which layers have priority of placement under the advanced tab. For instance, you might want to give country labels priority over city ones.
Now down at the bottom, you should see a status bar with several items on it. First a set of coordinates for the present location of your mouse, second, is the current scale, third are some controls for re-rendering, which can be useful when large data sets cause the program to lag, and fourth is the current coordinate system, which should be greyed out.
The current coordinate reference system (CRS) should be EPSG:4236, or if you hover over it, it should tell you that's WGS84. EPSG is the European Petroleum Survey Group, an organization which has listed a large set of common coordinate systems and given each a specific number, in this case they have assigned the number 4326 to the WGS84 datum, one of the most widely used datums for worldwide use. If you look at the coordinates box, you'll see that they are in the range of -180 to 180, and -90 to 90. That is, they are the latitude an longitude.
Now lets change to a projected coordinate system. Click the little globe icon beside the CRS indicator. This will bring up the CRS properties.
Now, so far the data in the shapefiles has been in the same coordinate system as the map. They have both been WGS84. Now we are going to change that, but we need to tell QGIS to adjust everything to match automatically. This can be slow, and sometimes a little buggy so it is turned off by default. Click the check box at the top to enable it and then click apply. In the main window, the CRS indicator should turn from grey to black.
Now, open Projected Coordinate Systems, Equidistant Cylindrical, and select WGS84 Plate Carree. Then click apply again.
The map is now in the Plate Carree projection. This means that distances along the equator, or straight north-south are correct, and in this case measured in metres. Close the properties and go back to the main widow. You may need to zoom in or out to make things update. Now, where you had degrees, you now have metres, so everything is much, much bigger. In fact you probably only see one big field of colour from a single feature. So Zoom Full to see the whole map.
That really doesn't look all that different, but it is. Move your mouse and watch the coordinates. They are now up in the millions because it's all in metres now. The first is in distance along the equator, and the second is north or south. Both have had large numbers added to them to eliminate negative numbers. Obviously, the scale doesn't work for other distances, the poles have been stretched out by the projection. Select Canada from the countries layer and zoom to it. The arctic islands are a very good example of the distortion. Lets pick another projection to fix that.
Open the CRS properties again and change to Lambert Conformal Conic. There are a lot of LCC projections so to find the one we want so lets do a search. Down at the bottom of the list, select Search by Name, enter "Statistics Canada" and click Find. This should bring up NAD83 / Statistics Canada Lambert. If not, click Find again until you get it.
Apply, close the properties, and Zoom to Selection to re-centre on Canada.
That looks much better, although the ocean has disappeared. Also, if you zoom out, you'll see that other parts of the world have very serious distortion. Antarctica has even been turned inside out. Try turning the countries and land off, and you'll find the same thing has happened to the ocean. Normally we would be working with shapefiles that only contain regional data when making a regional map, which would solve this problem. I'll cover creating a clipped and reprojected shapefile later.
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