Compositing mode question

[Ian Stark]

I have a piece of generated media which I have resized into a bar that I want to float down over a list of text.

It's a simple Solid Color with about 50% opacity (set in the media). I resized and shaped the generated media using Track Motion and keyframed the path of the bar using Track Motion as well. I'm sure there are other ways to achieve the same result using pan/crop for instance. This is just the way that works for me.

I'd like to change the compositing mode of the bar (or the text?) so that as it passes over the text it darkens the text (i.e. the text is pale until the bar passes over it then the sum of the bar and the text makes the text darker). Hope I'm explaining this clearly!

No matter what I try I can't seem to get this right. Could someone who has a spare moment give me a quick break down of what I need to do in terms of setting up tracks and the correct compositing mode to use?

Much appreciated.

[Dugi Barr]

Hi!
I can do this with black as the solid colour and set to 50% Level on a track above white text.
Solid Black set to "Source alpha".
It also works with track level at 100% and Solid colour opacity at 50%

[David Jimerson]

What's the background of the text? A compositing mode will affect the entire image, not just the text.

[Ian Stark]

Yep, exactly as I have discovered!

The text background is a transparency. Underneath the text is a semi-opaque box and underneath that is footage. It's a shame that the compositing mode doesn't affect only the media as sized on that track, rather than the entire frame. That seems like a shortcoming to me, or am I not thinking this through properly?

Dugi, thanks for the input - I was really trying to do this so the text changed colour but I may now go black and white!

[Graham Bernard]

Well, is THIS what you are after?

http://dl.dropbox.com/u/20371960/DvInfo/test.mp4

Grazie

[Ian Stark]

Grazie, that's almost exactly what I'm looking to do (with different colours, but the principle is there).

How did you set that up?

Many thanks for taking the time, much appreciated.

[Ian Stark]

Just a little rider to my last post - what I had hoped for was to actually see the bar as it travels down, pauses for a moment on the first line of text, travels down to the second line, pauses etc.

Here's the sort of thing I'm trying to achieve http://www.youtube.com/watch?v=yeSRPI3vu9I (love this easy upload to YouTube!). What I did in the end was to create a separate project to achieve the effect I was looking for, but if it can all be done in one veg I'd be happier. This quick test doesn't have the pauses on each line and the colours are not as I want them, but you should get the idea.

[Graham Bernard]

The pausing is straightforward. See next.

If I could upload the VEG you could have it with pleasure . . seeesshh . .

I can't open the Youtube . . says its private . .

http://dl.dropbox.com/u/20371960/DvI...Child%202a.mp4

Grazie

[Graham Bernard]

Hah! Done it . . .

G

[Ian Stark]

Sorry Grazie, forgot you have to set it to 'unlisted'. Now why doesn't the Vegas YouTube uploader give you that option?!

Sure, the pause bit is easy - it's the compoositing bit I was struggling with.

Aha, just seen the veg is up (well done!). I'll take a look. Cheers!

[Ian Stark]

(By the way, I've changed it to unlisted now if you wanted to take a look)

[Ian Stark]

Played around with the veg and have got it almost there. Using screen mode gets me close but actually using overlay works even better, giving a nice black bar. I took out your track motion keyframes, by the way - made making the colour/shape changes a lot easier!

Here (hopefully) is the edited veg.

Thanks for the input. Not sure what I was doing wrong before, because your method is almost exactly mirroring what I had set up before in terms of child/parent relationships. I must have been having a bad moment (one of many).

Thanks again.

[Gerald Webb]

Hi Ian,
I know you mentioned doing it in one Veg, but if you just nest one veg it is so easy.
I downloaded your vid,
masked the text box and dropped in a new comp, so you just have the box with an alpha background.
Put a solid over your highlighted tex and crop to size,
Make the solids compos mode Difference, animate it to suit, save,
Drag the Veg back to your first comp over your animated background.
Done
:)

[Ian Stark]

Hi Gerald - indeed, nesting! That's what I was meaning when I mentioned how I had achieved the effect in one of the earlier posts. I am having much more success with nesting on my new whizzy box.

To be honest, my reasoning for wanting it in one veg was only a) for tidiness, b) to have less bits to lose and c) out of curiosity to learn more about compositing modes. I consider myself to be someone who pushes Vegas a fair bit, but parenting and compositing modes are areas I've never really explored.

Must try harder!

Thanks all for advice.

[Ian Stark]

By the way, Gerald, your method (as is Grazie's) is more elegant than mine. I shall keep that to myself . . . ;-)