strange videoplane behavior...?

vodstrup's icon

It's been a while since I've worked in Max, and I hopefully am just making a simple error but...

I'm using the alpha in the color attribute to fade a videoplane. This is something I've done in many other patches, but I cannot figure out why it isn't working here... It should be simple. When I turn on the metro to put the sampled matrix through, the videoplane/jit.window stays black.

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Max 6.0.8
on a MBP running 10.7.5
AMD Radeon HD 6770M

Rob Ramirez's icon
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you are passing an alpha plane of 0 (the output from the absdiff of two fully opaque alpha planes is 0). simply pack in the alpha plane prior to the subtraction:

vodstrup's icon

Much thanks! I think I'm grasping this - though I don't recall ever having had to do this before (as such, I'm thinking that several old patches need an update...)

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Could I please ask one more favour? Is this the way it might work best in a slab?