{"id":1922,"date":"2018-03-15T08:11:03","date_gmt":"2018-03-15T08:11:03","guid":{"rendered":"http:\/\/blogs.lincoln.ac.nz\/gis\/?p=1922"},"modified":"2023-05-07T03:36:25","modified_gmt":"2023-05-07T03:36:25","slug":"contour-labels-made-not-so-easy","status":"publish","type":"post","link":"https:\/\/blogs.lincoln.ac.nz\/gis\/contour-labels-made-not-so-easy\/","title":{"rendered":"Contour Labels Made Not So Easy!"},"content":{"rendered":"

In previous posts we looked at deriving elevation contours and creating index contours for display.\u00a0 This time we look at the not quite so straightforward task of labeling our contours.<\/em><\/p>\n

So previously we’ve covered how to derive contours<\/a> from elevation data and then create some nice index contours<\/a>.\u00a0 The last piece of this puzzle is labeling, which turns out to be a bit more challenging than one would hope, so let’s finish this off so we can move on to other topics.\u00a0 We’ll continue working with our nicest set of contours from our previous efforts.<\/p>\n

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Recall how I foolishly set my indices as ‘Bret’ and ‘Jemaine’.\u00a0 What was I thinking?\u00a0 Let’s start things off by labeling all my contours using the attribute values in the Contour layer.\u00a0 We get at the labels by going to Properties > Labels:<\/p>\n

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I’ve already set the Label Field to Contour.\u00a0 To turn the labels on I can tick the wee box at upper left: “Label all features in this layer” with this result:<\/p>\n

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It’s a bit of a mish mash and I can go a long way to improve these.\u00a0 First off, I’d like to change the font colour so that it matches my contours a bit better – that’s easily done from the Labels tab:<\/p>\n

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This is only a slight improvement.\u00a0 Next up I’d like to set my labels in the middle of my contours rather than all being horizontal.\u00a0 I can do this from the Placement Properties button on the Labels tab:<\/p>\n

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Notice that I’ve set the Orientation to “Parallel” and the Position to “On the line”.\u00a0 Here’s what I get:<\/p>\n

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Now we’re getting somewhere!\u00a0 One more little tweak and we can almost call it quits.\u00a0 See how the line goes through the label?\u00a0 To have the labels interrupt the contour line, I’ll create a “halo” around them.\u00a0 From the Labels tab click on Symbol:<\/p>\n

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Then on the next window, click “Edit Symbol”<\/p>\n

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And then click over to the Mask tab:<\/p>\n

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Tick the “Halo” button and adjust the size to your liking.\u00a0 Increasing the size makes the halo around the label wider (if only it were so easy in real life…).\u00a0 Here’s the result:<\/p>\n

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That’s looking nice, eh?\u00a0 A bit more professional.\u00a0 National Geographic, here I come.<\/p>\n

Ah, but wait.\u00a0 Most topographic maps you’ll see only label the index contours, just to cut down on all the clutter.\u00a0 All is not lost – we can make use of our Index attribute values to only label the index contours.\u00a0 Back in the Labels tab, I’ll change the Method to “Define classes of features and label each class differently”<\/p>\n

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This adds some new options onto the tab, one of which is “SQL Query…”\u00a0 Those of you who love doing queries (and who doesn’t) will recognise the window that pops up when we click that button:<\/p>\n

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It’s our old friend the query window.\u00a0 We can use this to build a query to find all the contours where the Index value is “Bret”:<\/p>\n

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When we click OK and eventually get back to the map, here’s what we get:<\/p>\n

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Sweet as, bro.\u00a0 Now only my index contours are labelled and they sit nicely in line with the contours.\u00a0 I should probably leave well enough alone but there’s just one more tweak I’d like apply.\u00a0 Because labeling is such an important part of mapping, there’s (not surprisingly) a specific toolbar for labels.\u00a0 You get to it in the normal way of either right-clicking on the grey menu area and selecting the the Labeling toolbar or going to Customize > Toolbars and adding it.\u00a0 It’s deceptively simple looking:<\/p>\n

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There are several things about this toolbar I’ll ignore but the one I will focus on is the Maplex Labeling Engine<\/a>.\u00a0 Turning this on gives you some more labeling options and a few that are contour-specific.\u00a0 Turn it on from the Labeling menu:<\/p>\n

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Selecting :Use Maplex Label Enginer” turns it on and gives us a few more options in the Labels tab, particularly with the Placement Properties, which now looks like this:<\/p>\n

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In this image you can see the different placement options and one specifically for contours.\u00a0 Again, lots of tabs and menus to delve into but we’ll keep it pretty limited.\u00a0 With “Contour Placement” selected, click on Position and you can see how we can choose different placements – I picked “Centered Curved”:<\/p>\n

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I also set it to use “laddering” from the Options button:<\/p>\n

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After ALL that…:<\/p>\n

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Well I hope that this isn’t too underwhelming after such a big build up – some very subtle changes have been made and I have to say that I’m pretty happy with the outcome.<\/p>\n

NB: and it’s a pretty big NB: once we start adding other layers, we might well be getting some conflicts with other features.\u00a0 There are some conflict resolution options with Maplex that will help but if it starts getting complex, you may well end up manually placing labels, but let’s not even think about that one.<\/p>\n

So over these three contouring posts we’ve covered a fair bit of ground.\u00a0 Starting from a DEM, we derived our contours, smoothed them to get a nice effect (good for mapping, not analysis!), then set up some index contours and finished off with labeling.\u00a0 Hopefully there are some other useful skills we’ve hit upon that can be used on many types of layers, not just contours.<\/p>\n

Keep those cards and letters coming!<\/p>\n

C<\/p>\n","protected":false},"excerpt":{"rendered":"

In previous posts we looked at deriving elevation contours and creating index contours for display.\u00a0 This time we look at the not quite so straightforward task of labeling our contours. So previously we’ve covered how to derive contours from elevation data and then create some nice index contours.\u00a0 The last piece of this puzzle is […]<\/p>\n","protected":false},"author":3,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[1],"tags":[],"class_list":["post-1922","post","type-post","status-publish","format-standard","hentry","category-uncategorized"],"_links":{"self":[{"href":"https:\/\/blogs.lincoln.ac.nz\/gis\/wp-json\/wp\/v2\/posts\/1922","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/blogs.lincoln.ac.nz\/gis\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/blogs.lincoln.ac.nz\/gis\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/blogs.lincoln.ac.nz\/gis\/wp-json\/wp\/v2\/users\/3"}],"replies":[{"embeddable":true,"href":"https:\/\/blogs.lincoln.ac.nz\/gis\/wp-json\/wp\/v2\/comments?post=1922"}],"version-history":[{"count":1,"href":"https:\/\/blogs.lincoln.ac.nz\/gis\/wp-json\/wp\/v2\/posts\/1922\/revisions"}],"predecessor-version":[{"id":4124,"href":"https:\/\/blogs.lincoln.ac.nz\/gis\/wp-json\/wp\/v2\/posts\/1922\/revisions\/4124"}],"wp:attachment":[{"href":"https:\/\/blogs.lincoln.ac.nz\/gis\/wp-json\/wp\/v2\/media?parent=1922"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/blogs.lincoln.ac.nz\/gis\/wp-json\/wp\/v2\/categories?post=1922"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/blogs.lincoln.ac.nz\/gis\/wp-json\/wp\/v2\/tags?post=1922"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}