Alpha Matte Multiple Layers while keeping Parent Properties

[jcushman329]

I have an icon sent to me by a designer from Illustator that comes in a few parts (a bird with a body, right wing, a left wing, and a bigger icon beind it). Along with that, they also sent over masks that go behind the two wings, to prevent the reveal of the bigger image behind it. The illustration style of the wings is very stroke-like, so there's some transparency in different parts of the wings, but they want the wings to look like they're covering the image behind it.  I have the wings change position over time, to which I parented the corresponding masks to those wings, so that it would move along with it. 

I was able to Alpha Matte one of the wings to the wing mask, but I'm at a loss on how to achieve this look with the other parts of the icon, while still masking the moves of the wings and keeping those parent properties. Is there an expression I can use to achieve this?

[Warren Heaton]

I hope this isn't too obvious of a question:  Does the birt artwork have a fill as well as a stroke?  Seems like you just need to  fill to cover the layer(s) behind it.  Or, if doing the Track Matter route, use the fill as the Alpha Matte.

[jcushman329]

Hey Warren, I just posted a reply to Rick with some screenshots of my comp to help explain better. I have the background changing color with a gradient over time, so I wouldn't be able to just fill the background with a simple color. I'm also using these same icons in different places, so I'd like to be able to just throw the comp and have it be transparent to wherever I need it to go, if that makes sense. 

[Rick Gerard]

Your cropped screenshot shows nothing about your comp. What are you using for the matte? If you have two layers that have fills for the wings pre-compose both layers and use the pre-comp as a track matte for the logo or the background. The background would probably be easier. If you have multiple layers you need to matte then you can either use Set Matte on each layer and point to the pre-comp or you can duplicate the pre-comp in the main comp and start stacking things up.

This kind of layering and matting is really basic stuff. If none of what I suggested makes sense then I strongly suggest you use the Search Help panel in the upper right corner of AE to consult the user guide.

The other option is to post a screenshot of the comp with the modified properties of the layers that are giving you problems revealed. Select the layers, press UU, Take a screenshot and post it. Let us know what the Matte layers by having one of them selected in the Project Panel so we can see the preview. When we have something more than a guess to go by we can probably point you in the right direction.

[jcushman329]

Hey Rick, thanks for your quick reply. After posting I realized I could have explained a lot better.

Here's a screenshot of a similar icon, with only one element in the foreground and one in the background. I was able to achieve this with just an Alpha Inv. matte.

Here is the Dove icon, with the background pre-comped, and the foreground icon elements inside the comp. I was able to mask the sword using the same method I did for the crown icon above (alpha inv.), but I'm left with the body and left and right wing to mask. I would pre-comp them, but the body layers have their masks (shown in white) pareneted to them, as the wing rotates up and the body slides up. I want the white masks to follow the same moves as the body parts, but pre-comping removes the parenting. Hopefully this shows a little better at what I'm trying to achieve.

[Rick Gerard]

Let's just start with layer 1 Body Outlines. I see an End keyframe so I am assuming that there some kind of shape animator on that layer like animate position and rotation.

Below on layer 4, I see another shape layer named Body Mask Outlines. I am assuming that this layer has a white fill. I would know a lot more if you selected the Body Mask Outlines layer and pressed the U key twice so there was some indication of what you are doing in the layer.

I might be wrong about how you are rotating the body and moving it up. If parenting is working then you are not using a position and rotation animator, you have animated the position and rotation of the layer. If parenting is working and the move is working and the body mask moves as it should all you have to do is turn off the visibility of the body mask layer and apply Set Matte to all of the layers you want to hide. 

The screenshot helps but I still don't know exactly what you are trying to accomplish. 

If this was my project and I wanted to rotate and move the drawing of the bird in front of the bottom nested Elements comp I would just pre-compose everything that makes the bird outlines to one comp called bird and the everything you want to use as a matte for the bird into a bird matte comp, turn off the bird matte comp and use Set Matte on Elements. The other option is to group all of the mattes in a single pre-comp and use that as a track matte for the elements layer. 

If everything is moving with the same animation then you can tie things together with simple pickwhip expressions even across comps. It's pretty easy to do.

I could give you a better explanation if you gave me more workflow and design ideas. Let me take one more try. As I look at your comp and read your explanation again I think that you have a sword and a bird that move into place the way you want them to and you want them to cover the bottom layer so you don't see the lines in the element layer. I also think that you don't want to just put a black background on the sword and bird images to hide the lines of the bottom layer. If that is the case and you don't want to go through the trouble of using expressions to tie the animation in one comp to the animation in another comp then there is a much easier solution. Just add 4 copies of set matte, Left Wing, Right Wing, Body and sword mask outlines to the Elements layer and then turn off the visibility of all matte layers. All that is left is to invert the matte in every instance of Set Matte so it makes holes in the "elements" layer.

[jcushman329]

Your 5th paragraph was exactly it! I've never needed to parent across comps and totally forgot about the pick whip and set matte. I was able to get the look without having to comp each element separately in your last paragraph, just had to pre-comp the bird and its mattes. Thanks so much for your thorough explanation!