I believe what John has described has to do with reversing things like Gobo Rotate.
As far as I know, you can't reverse Effects. (With one exception, see below) And you can obtain symmetrical effects depending on the rig setup.
For instance, with a row of Movers under a truss; Get the desired Effect running, like a Tilt Effect Press and hold FAN and then select Center from the bottom right monitor. While still holding Fan adjust the Effects Offset Encoder.
With movers on either side of the rig; If you apply a Sine Effect to the Pan then you will need to enter a 180 degree offset on one side of the rig. Because it is a Sine wave the result is an apparent "reversing" of the Effect on that side.
I can't believe that it has been twenty years, since the start of the whole hog range and there is still not a reverse direction for the effects engine.
It's all how the fixtures are selected (or fanned).
For example, rainbow effect running left to right...
Select fixtures left to right Hit Rainbow and fan 0 thru 270
For rainbow effect running right to left...
Select fixtures right to left Hit Rainbow and fan 0 thru 270
OR
Select fixtures left to right Hit rainbow and fan 270 thru 0
Now it's going reverse.
Change the direction of the fan and it will go the other way.
You can also split from center by using 0 thru 270 thru 0
The engine is powerful and you can pretty much do what you want. Just takes a little practice and playtime. Once you understand the use of offset and ranges, you'll get places in no time.
