Invert Opacity between two values with two layers


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Invert Opacity between two values with two layers
by Chris Arnold on Feb 23, 2009 at 3:41:04 pm

I am trying to get an expression that will translate the value of one layers opacity to another layer. One layer is keyframed on each frame either being 18% or 0%. I need another layer to look at these values and everytime the keyframed layer's value is 18 percent this layers opacity should be 0%, and when the other layer is 0% this layer should be 18%.

Any help would be great!

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Re: Invert Opacity between two values with two layers
by Trent Armstrong on Feb 23, 2009 at 4:18:06 pm

temp = <opacity value>;



if (temp == 18) 0 else 18





OR





temp = <opacity value>;

Min = 0;

Max = 18;

value1 = 18;

value2 = 0;



linear(temp, Min, Max, value1, value2)

If you're using Hold Keyframes, you could use an IF statement. Otherwise you could use linear().

Trent Armstrong - Creative Cow Leader
http://www.dallasaeug.com

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Re: Invert Opacity between two values with two layers
by Chris Arnold on Feb 23, 2009 at 4:54:34 pm

Thank you, that is helpful.

It came to me probably an easier way to do this. If you pickwhip the opacity to the layer with keyframes and then subtract 18 from that value it will give what is needed.

So, (18 - Pickwhip)

Thanks

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