Is there a document describing all the shapes?

[peter.rodda]

Hi,

Is there some documentation describing how each shape works?

for instance, what is the difference between Pan swing and Pan saw?

Also would be handy to have notes on which shapes need the attribute to be at a specific value to get the full effect of the shape out (e.g. having CMY attributes at 50% for rainbow shapes to work properly).

[niclights]

I suspect the answer is no.

Pan swing uses a sinewave pattern to modify values. Pan swing uses a 'sawtooth' pattern (IMO actually trianglular, but hey). So swing will smooth it off where it changes direction, saw will not.

You could open shape.xml, copy the pattern values into excel or similar and plot graphs but there aren't really that many patterns and they're fairly simple.

With the exception of the 'step' shapes, they all work on both negative and positive offsets. So it is this that you need to consider when working out what a shape will do and therefore where your origin needs to be.
The only other shape I can think of that needs specific values to get working properly is dimmer which ideally should have origin 50%, size 50%. Personally I don't like this so I wrote ones that only work on positive offsets (see tips thread). Rainbow, however, cannot be cheated in the same way.

[peter.rodda]

I never kew that about the dimmer shapes... I usually have used them at 100%.

I used to be able to put a pan swing/saw on one mode 2 fader, and a tilt swing/saw on another mode 2 fader. Then combining them would give a circle. But lately all I get is a V shape. Should I have an off set in one of the shapes? I think I have tried an offset of 180 and it didn't seem to help.

[icke_siegen]

yeah, 90° offset would give a circle. 270° offset would reverse the circle (or 0°, and 90° offset for the other shape). That's how the circle shape is created.

You may have a look at the shape.xml in the PersonalityLibrary; it will give you a quite good start. Each pattern consists of 64 steps, with values between -1000 and 1000.

[niclights]

Note that while the pattern values -1000 to +1000 are essentially arbitrary, they translate to -256 to +256 (or thereabouts) in DMX when used in a shape with size at 100%.

This is very useful as it means a channel can be offset to zero or full from any origin but it is also the reason why things like dimmer might need specific size and offsets.
For example, if you have a dimmer origin of zero and a dimmer spread at full size it will smoothly fade up to full and back down following its sine curve but when it reaches zero there will be an equal amount of delay while it performs the negative offset that cannot be seen. The opposite occurs with origin at full where it will hold during the positive part of the pattern.

Sometimes this 'chopped' wave can be deliberately used for effect (and in the case of rainbow is actually essential) but if you want a totally smooth wave then you must set an origin and size at 50%.