|Rummaging in the Toolbox: Rotating Symbols|
|We're always looking for a better way to tell our story using MapInfo Professional. Many of us rely on features such as thematic mapping and labelling to get the message out.|
Another visualization capability, to add an additional dimension to your maps, is a tool called "Rotate Symbols". This allows you to rotate symbols based on either a column of numeric values. A fixed value can be specified as well but for this article we will emphasise linking a value in the data to the amount that the symbol is rotated.
Here are "before and after" screenshots.
The symbols in the map above have not been rotated.
This is easy to do! The default drawing style accessed from the Layer Properties dialog box. In Layer Control, Double-click the layer name or select the layer and click the Layer Properties button.
In this map, the symbols have been rotated, according to a value in the table.
First, run the tool by navigating to Tools > Tool Manager and load Rotate Symbols. Next, open a table of points. If you have table with numeric values, use that for experimental purposes.
First, save a copy of your table (File > Save Copy As). Open this new copy. This is necessary because the Rotate Symbols tool makes permanent changes to your table.
Navigate to Tools > Rotate Symbols. The following dialog will appear.
Be sure to save a copy of your table first!
Here you'll choose the table to process. Within the Rotation group box, specify the column to use or a fixed rotation value in degrees. Within the Symbol group, identify if you only want to rotate TrueType symbols, only rotate those symbols that are "rotatable" or replace all existing objects with a new symbol.
Keep in mind this tool will only work with TrueType fonts. This is basically all symbols with the exception of custom symbols (which are bit maps and other image files) and the MapInfo 3.0 Compatible symbols.
Also, once again, this tool will edit original symbols. Consider using File > Save Copy As on the original table to create a backup. You can also use File > Revert Table to undo the edits you have made.
If you are satisfied with the changes you have made then use File > Save Table to save the changes you have made.
Looking for good symbols to rotate?
The MapInfo Cartographic font has a number of good arrows or other "pointy" symbols you might choose.
Also the WingDings font has some good possibilities. Rotate Symbols uses an arrow from Wingdings as the default choice. Check out rows 24 through 27.
Want even more MapBasic tools?
Check out all of the articles in this section of the journal for many more useful tools and utilities.
Here is a link to the archive of all of the previous issues of "The MapInfo Professional" journal.
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Article by Sue Disy, Senior Sales Engineer
When not writing articles for "The MapInfo Professional" journal, Sue works with Pitney Bowes Customers all over North America as a Sales Engineer. When not working Sue enjoys staying active. You may find her horseback riding in the Adirondack mountains, practicing yoga, enjoying personal travel or staying home and cooking in her kitchen.