Re: [LCtalk] Fwd: Clear Cue

[Fokko van Duin]

At 18:07 +0200 08-08-2007, P. Koelman wrote:
> Ok, so:
> you tell a layer to set a certain set of dmx-channels to a value you 
> give tell a higher layer to set the same set of dmx-channels to a 
> different value then the mixer applies the rules for the layers and 
> decides which value should go to the dmx-output.

Correct, if the highest layer is Copy, lower layers are disappeared. 
If it was in e.g. HTP mode the highest value of the current layer and 
the result of lower layer incl mixer will be the new result.


> BUT, the mixer ONLY looks at the active channels.
> So if a channel is active with value 255 in Layer A, and with the 
> command g0a inactivate all channels, the mixer will see no change, and 
> the output willl still be 255 on that channel.
> Is this correct?

Yes.


> I allways have a 'Background' layer as a bottom layer, so the mixer 
> will allways see a value for each channel.

correct.


> Just out of curiousity, why does the mixer not recognise an inactive 
> channel as set to zero? Is there a situation where you want the mixer 
> to remember the last known status of a channel before inactivation?

A layer is like a desk for n channels. If n has become 0, there are 
no channels for this layer. Remembering the last state in the mixer 
is essential for calculating fades with a newly started cue. Also for 
moving heads all 0 is be a very bad idea (shutter closed, head moving 
to max left top corner)


> Is there anyway to clear or reset the mixer to set all channels to 
> zero?

Yes, create 1 cue with all zeros, or better create a cue representing 
black-out. I would bring moving head to center, or use no change for 
pan/tilt (left them where they are).



Fokko van Duin,
CDS advanced technology bv,
http://www.lanbox.com/