Title reveal is easy enough. The masking tool is readily available in the Effects panel under the "Text" item you're working on. Use motion and the title is revealed as it enters into the mask. I want to do exactly the same thing with a png graphic logo, but I cannot figure out how to mask. Google keeps giving me opacity masking options that are not relevant. You're help will be most appreciated!
Is it PNG with alpha channel? Or it has some uniform background?
With alpha channel
I'm using CC 2015 and I'm not entirely clear on the issue so forgive me if this isn't what you're asking, but for a basic reveal mask in '15 I'd do the following;
Make your mask as a shape layer (so use the rectangle tool or the pen tool, or what have you depending on what shape you need the mask to be. Position the shape layer where you want the mask to be. Make sure your shape layer has a fill (I usually set it to White)
Put the shape layer directly above your .png file. Now on your .png layer, go to the track matte option next to the 'mode' column on your layer editor (you may have to hit 'toggle switches / modes' at the bottom if you don't see a TrkMat option) and select either 'Alpha Matte' if you want the Shape layer to be where the .png is revealed, or 'Alpha Inverted Matte' if you want the shape layer to hide the .png and then you can animate the .png outside of the shape layer (which at this point is basically a mask). You can then precomp these two layers (the shape layer and the .png) so that it's one entity if you'd like.
Is that helpful?
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