This module is designed to supply a single number which can be fed into other modules, such as OrthoSlice as the slice number. It can usefully used to allow fine control over numeric parameters - for example, a number can be single stepped by an EXACT set step in either direction. This is useful for stepping through values in an orderly fashion, as the slider widget at present doesn't allow single precise-stepping. Simply wire the Current Value outout parameter into any other parameter that you want to control.

Briefly, the VCR(well, sort of)-ish buttons are : F single steps forward. R single steps backward. FF sets value to end. RR sets value to start.

Fire starts chucking out numbers from the set bounds, according to the settings of the radio buttons.

In additon, the module can be used as a basic animation system by setting the Start and End sliders, choosing some other stuff, and hitting the Fire button. The button will simply pump out all the relevant numbers - note that it doesn't do anything fancy like using timers ! The numbers are simple thrown out on the Current Value port. This seems to work, but maybe when many many numbers are generated the sytem might get confused - ah well...Anyway, every time you hit the fire button, the module will generate the correct chain of numbers, as set up by the sliders and buttons. If you generate lots on a slow SGI, then disabling the yellow firing bar on modules is highly recommended.

Finally, this was written very quickly as a test of the Module Builder - it doesn't claim to be a brilliant bit of code, but has worked for our purposes.

It also does a bit of checking to keep Start always less than End, and keeps the bounds on the Current Value sensible.



Port: Start
Type: Slider
The start value for any animation - this is also mapped onto the lower bound of the Current Value

Port: End
Type: Slider
The end value for any animation - this is also mapped onto the upper bound of the Current Value

Port: Step
Type: Slider
This value is the step that will be applied to any operations on the VCR-type buttons.

Port: Repeat
Type: Slider
How many times to repeat the fire operation - only activated when the N-Times button is selected.

Port: Direction
Type: Radio Box
Menu Item: Forward
Menu Item: Backward
Menu Item: FlipFlop
Which way to step when the firing commences. Backwards (from End to Start), Forwards (vice versa), or FlipFlop (forward then backwards)

Port: Current Value
Type: Slider
The important slider ! This is the one you typically wire elsewhere.

Port: Fire
Type: Button
Firing/Animation sequences are only activated when this is pressed.

Port: Mode
Type: Radio Box
Menu Item: Once
Menu Item: N-Times
Whether to do the animation/firing sequence once, or N-Times (in which case the N is taken from the Repeat slider)

Port: FF
Type: Button
Set the Current Value to End.

Port: RR
Type: Button
Set the Current Value to Start.

Port: F
Type: Button
Set the Current Value one step unit higher.

Port: R
Type: Button
Set the Current Value one step unit lower.



Not really any problems, except that its not the best module under the sun.

If you start a module firing on a long sequence of numbers, it may take an age to get through them, and you can't interrupt the flow !


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© The Numerical Algorithms Group Ltd, Oxford UK. 1996