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Issue 4.2


Control Panel Library

Circular Gauge Class

Issue: 4.2 (November/December 2005)
Author: Joe Nastasi
Author Bio: Joe Nastasi is the president of Pyramid Design, the developers of A-OK! The Wings of Mercury, A-OK! Spacecraft Simulation System, and FTP Suite.
Article Description: No description available.
Article Length (in bytes): 7,029
Starting Page Number: 36
Article Number: 4217
Resource File(s):

Download Icon 4217.zip Updated: 2013-03-11 19:07:59

Related Link(s): None

Excerpt of article text...

In this installment of Topographic Apprentice, we'll take a look at the final control panel element, the CircularGaugeClass. As we shall see, this class is a bit more complicated than the other two control panel elements.


The CircularGaugeClass can display multiple values at once. Each value is assigned to a needle in the gauge. An altimeter, for example, can have two or three needles, each representing a different range. In the example project there are two needles, one for 0 to 1000 feet and the other for 0 to 10,000 feet. As with the others, it is based on the PanelEntityClass, which provides basic functionality and properties.


GaugeStart as Double -- A local property that indicates where the zero location will be, as indicated by an angle of 0 to 360 degrees, where 0 is at the top of the gauge.

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