Archive for July, 2006

Wednesday, July 26th, 2006

iTools identifier browser

Every component in the iTools has a unique identifier placing it in a hierarchy of components for the tool. This identifier is necessary to programmatically use the component. So how do you find the identifier of some component? The standard technique is to use the IDLitTool::findIdentifiers method. Alternatively, MG_ITBROWSER allows interactive browsing of all the […]

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Tuesday, July 25th, 2006

Timer events to process a task in the background

This program is an example of using timer events to do a task in the background while allowing the the user interface to still respond to events. This technique requires the background task to be split into parts which are short enough for each part to complete quickly enough for a user to not notice […]

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Friday, July 21st, 2006

Rendering order in the iTools

When rendering object graphics atoms with transparency, the order the atoms are rendered (i.e. the order the atoms are created and added to the hierarchy) determines what can be seen. You want to draw the atoms from back to front when the front items are transparent. The same principle holds true for iTools since they […]

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Monday, July 17th, 2006

Create isosurfaces programmatically in iVolume

The iTools are easy to use interactively (O.K., easy once you learn some of the conventions and jargon). But they also have the ability to be extended and controlled programmatically. I have given a couple examples of extending an iTool with new operations (data operation, general operation). I’ll post more extending iTools visualizations, file readers/writers, […]

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Friday, July 14th, 2006

12 tips for beginning IDL programmers

I have accumulated the following tips over years of dealing with new IDL users. They are all fairly simple ways to get more out of IDL. Some of them can’t really be described in a paragraph, but it gives you a starting point of something you might want to check out later. If you have […]

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Tuesday, July 11th, 2006

Perceptual Edge website

Perceptual Edge has a library of excellent articles written by the Stephen Few, author of the site. His examples were also informative; each example analyzes and redesigns a statistical graphic. The discussion groups have some thoughtful ideas, but are not as useful as Tufte’s Ask E.T. forum. (By the way, I wish the website was […]

2 Comments » - Posted in Visualization by

Friday, July 7th, 2006

Overview files for IDLdoc’ed libraries

Overview files are a simple way to give an introduction to a viewer of your IDLdoc’ed library. The main overview file is simple to specify when you run IDLdoc. For example, to specify the file “overview” in the current directory, use: idldoc, root=my_root, overview=’overview’ when you IDLdoc your library. There are also directory specific overview […]

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