Improving Out-of-Pegs inbetweening system

[D.T. Nethery]

I realize this has been discussed before , but it's been a while since the topic came up and I think it is time to talk about it again.

For inbetweening "out of pegs" (aka "off pegs" ... for "shift & trace") if I do it on paper with drawings shifted off the pegs

inbetween off pegs.jpg (77.25 KiB) Viewed 29764 times

when I put the drawings back on the pegs, the inbetween drawing will be in registration with the other two drawings , half-way in the middle of the other two drawings, because of the pegs.

But in TVPaint when the drawings are returned to their original position the inbetween drawing position is still shifted out of place (not positioned in the middle) and then it must be manually re-positioned using the Transform Tool. (which is not ideal for clean-up inbetweening because Transform Tool subtly degrades the line quality, especially if the drawing has been shifted out-of-pegs and transformed several times). What I would like to request as an improvement for the Out Of Pegs feature is that when the drawings that have been shifted "out of pegs" are returned to their original position, the newly created inbetween drawing will automatically snap to the correct position between the other two drawings. Could this be done by using the peg holes symbols as a tracker that aligns the drawings ?

(in my note on the screenshot, where I wrote: "#7 also has peg hole symbols which are
aligned to the other two drawings" I meant to put it in the from of a question:
"Could #7 also have peg hole symbols that are aligned with the other two drawings ?" )

Then when the drawings are returned to their original position, the new inbetween drawing should snap
into position , half-way between the other two drawings -

[Thierry]

But in TVPaint when the drawings are returned to their original position the inbetween drawing position is still shifted out of place (not positioned in the middle) and then it must be manually re-positioned using the Transform Tool. (which is not ideal for clean-up inbetweening because Transform Tool subtly degrades the line quality, especially if the drawing has been shifted out-of-pegs and transformed several times).

Ok, so I'm in the same situation:

light-table_pegs_shift.PNG (80.04 KiB) Viewed 29754 times

My image on the right is tilted, like yours.


But when I go to the next image, the image is no longer shifted, even if the tilt parameters (the angle) are still in the Light Table, as you can see in the screenshot:

light-table_pegs_shift2.PNG (79.61 KiB) Viewed 29754 times

I'm not sure I understood the problem correctly

[slowtiger]

If I understand correctly, you are moving only 1 drawing out of pegs - then draw the inbetween - and then expect the inbetween to snap into position? This can't happen because you didn't tell the program where to snap to!

When I use this method, I first indicate the position of the inbetween (that's frame 0 in lightbox). Then I shift drawings 1 and -1 from the pegs (and tilt if necessary). Then I do the inbetween, then I press 0, and the two outer drawings snap into place - and the inbetween stays in the middle.

I think you expect TVP to somehow guess how much you want the inbetween tilted and moved, which is not possible. Only drawings which already exist and had a position before you put them off the pegs can snap back.

[D.T. Nethery]

When I use this method, I first indicate the position of the inbetween (that's frame 0 in lightbox). Then I shift drawings 1 and -1 from the pegs (and tilt if necessary). Then I do the inbetween, then I press 0, and the two outer drawings snap into place - and the inbetween stays in the middle.

Then I may have been doing it wrong all along ...

So I'm trying to it exactly as you say, but I don't understand what you mean by you "indicate the position of the inbetween" ... the inbetween frame is blank , so how do you mean you indicate the position of the inbetween ?

When I shift drawing 1 and -1 and do the inbetween, then click the X under frame 0 the two outer drawings snap back to their former non-shifted positions, but the inbetween is not in the middle , so I have to manually shift it using the Transform tool to get it to be in the middle.

Here is the process I'm following . Where am I going wrong ? ---

STEP 1 -

STEP 2 -

STEP 3 -

STEP 4 -

STEP 5 -

.

[slowtiger]

When I do inbetweens, especially those with wide spacing between frames, I first indicate the inbetween position of the character/object, just top and bottom, or a circle for the main mass. This way I mark the path of action and the spacing, before I shift anything off the pegs and do the clean stuff.

offpegs.JPG (69.83 KiB) Viewed 29734 times

As you can see, the blue sketch indicates where I want my #7 inbetween. Then I take frame 1 and 13 off the pegs, draw what I need, and put them on pegs again and add the rest. No need for shifting the inbetween because it never left its place.

(To word it differently: I put 1 and 13 off the pegs, whereas you put 7 and 13 off the pegs and left 1 in place.)

(When I started as assistant animator in 1990, we got some xeroxed pages with basic inbetweening knowledge. Minding the arcs was very important, so it became a habit to first indicate the position of anything, then do the drawing.)

[D.T. Nethery]

When I do inbetweens, especially those with wide spacing between frames, I first indicate the inbetween position of the character/object, just top and bottom, or a circle for the main mass. This way I mark the path of action and the spacing, before I shift anything off the pegs and do the clean stuff.

Yes, I get that . If you draw out visual markers first you can position the shifted extremes precisely. I've done that before. Thanks for clarifying that is what you meant .

So anyway, my feature request is that TVPaint would note the positions of the shifted drawings and when it snaps the two extremes back into their non-shifted positions it would also snap the inbetween into position half way between the two extremes. I know that what I'm asking for is not impossible because TB's off pegs inbetweening does it.

[slowtiger]

Ah, I've added some drawings in the meantime ...

The thing is that the inbetween is already in its correct position when you have put both outer drawings off the pegs.

[D.T. Nethery]

The thing is that the inbetween is already in its correct position when you have put both outer drawings off the pegs.

YES , but ... what I'm requesting is that the inbetween drawing, which is already in the correct position (because of the peg hole symbols embedded in it) would always snap back to the correct position because of those peg hole symbols being tracked for registration , whether or not any drawn guide marks had been previously established on the inbetween drawing . Does that make sense ?

[slowtiger]

The inbetween (the "0" drawing in the lighttable) is always in position and can't snap anywhere, not even back, because it never leaves that position. It doesn't move. You can only move the existing drawings befor and after that, and only they can snap back. I think this is the point where your thinking stumbles the whole time ...

Maybe try something with paper: tape one sheet to the table, this will be the inbetween. Get two more sheets with drawings, these are the frames before and after. You can move these two freely, but not the inbetween sheet. You could move the table with it, turn it around, but it will never leave its place on the table. But by moving the two other sheets you'll be able to inbetween any odd spacing.

[D.T. Nethery]

The inbetween (the "0" drawing in the lighttable) is always in position and can't snap anywhere, not even back, because it never leaves that position. It doesn't move. You can only move the existing drawings before and after that, and only they can snap back. I think this is the point where your thinking stumbles the whole time ...

Yes, I understand what you're saying. This works if you first plot out a rough version of the inbetween position to use as guidel to position the drawing before and the drawing after.

Maybe try something with paper: tape one sheet to the table, this will be the inbetween. Get two more sheets with drawings, these are the frames before and after. You can move these two freely, but not the inbetween sheet. You could move the table with it, turn it around, but it will never leave its place on the table. But by moving the two other sheets you'll be able to inbetween any odd spacing.

Ok, but I'm talking about is replicating what actually happens when inbetweening on peg registered animation paper. This is a new feature request , not about how the Out of Pegs function currently works.

Like the first image I posted above: I have two drawings: #1 and #9 . I'm going to draw the breakdown #5 , half-way between 1 and 9. Taking the drawings off the peg bar I use the peg holes and the edges of the paper to line up the drawings , so that the sheet of paper where I will draw #5 is positioned half-way between #1 and #9. #1 is on the bottom , next is #9 , then #5 is on top . After positioning the sheets of paper like this I tape them down at the lower edges . After I finish the inbetween and put these three drawings back on the pegs they are registered because they have the peg holes in common. Because the drawings which are off the pegs in TVPaint have peg hole shapes embedded in them I'm asking whether those peg hole shapes could be used to replicate what happens with traditional inbetweening off pegs on sheets of paper.



What I'm proposing is that if the drawings in TVPaint already have peg hole shapes embedded in them when using the Out of Pegs function why not use those embedded peg hole shape to actually register the drawings (otherwise , I wonder why are the peg hole shapes there ? What purpose is served by the embedded peg holes shapes ?) .

[slowtiger]

So you want another process added because you don't want to move that first drawing off the pegs?

It's doable, of course. In pseudocode it would be like:
- get position, rotation and scale of existing drawing -1 and drawing 1
- calculate imaginary off-peg position of inbetween 0
- set inbetween position to default when turning off off-peg.

I just don't get the benefits of that, because:
- it will only work for any straight-in-the-middle inbetween
- it will work for only 2 drawings visible in lighttable
- it will not improve line quality of the inbetween because it will be rotated/scaled in the end, thus giving you the same quality as with using the transformation tool.

[D.T. Nethery]

Thanks for pointing out the flaws in what I'm proposing . I will admit that I may be full of crap on this request and it's a request born of the false notion of fixing what is not broken.
I thought it was worth bringing up as a feature request. It would be great if a TVPaint developer could step in here to address the request and tell me if I'm completely wrong-headed in how I'm thinking about it.

However, I believe it is doable because both Toon Boom Harmony and Open Toonz do it that way. Inbetweening drawings off pegs in Harmony is much more efficient in my limited experience using Harmony. It is one of the things I actually like about Harmony. But neither Harmony or Open Toonz has drawing tools that are as good as TVPaint (and there are other things that do not make Harmony appealing to me. I prefer TVPaint , but there are things I'm saying could be improved. This is one of them, imo.)

- it will only work for any straight-in-the-middle inbetween

I don't think so , because in what I'm proposing the registration is based on the position of the embedded peg hole marks ... if you favor one extreme or the other in how you position the inbetween drawing between the extremes when it snaps the drawings back into place according to the peg hole positions , then the inb drawing will favor one or the other of the extremes, not be half-way in the middle. Just like in doing it on paper.

it will work for only 2 drawings visible in lighttable

In Harmony's version of off pegs that isn't the case. Why do you think it would be limited to only 2 visible drawings with TVPaint ?

Again, it would be nice if a developer from TVPaint could step in here and tell us if this is possible or not.

- it will not improve line quality of the inbetween because it will be rotated/scaled in the end, thus giving you the same quality as with using the transformation tool.

If that is true then that would be a huge issue and not worth pursuing this line of thinking.

[slowtiger]

Well, that last point should be obvious - with my inbetweening method, the inbetween stays in place, I draw it and it stays exactly like that. In that other method, the finished inbetween has to be transformed in some way - no problem if just shifted, but any rotation or scaling must be un-done while repositioning.

[Thierry]

- it will not improve line quality of the inbetween because it will be rotated/scaled in the end, thus giving you the same quality as with using the transformation tool.

That is my main issue with implementing David's idea (which is not a bad idea imo, as it offers another option to do inbetweenings, if I understood correctly)

Rotating and scaling bitmap drawings will always result in a quality loss, unless we can somewhat vectorize them, which I assume is what happens in Harmony.
Technically we could do that, but there's no way it can be done in the current engine (which is bitmap only).

[D.T. Nethery]

- it will not improve line quality of the inbetween because it will be rotated/scaled in the end, thus giving you the same quality as with using the transformation tool.

That is my main issue with implementing David's idea (which is not a bad idea imo, as it offers another option to do inbetweenings, if I understood correctly)

Rotating and scaling bitmap drawings will always result in a quality loss, unless we can somewhat vectorize them, which I assume is what happens in Harmony.
Technically we could do that, but there's no way it can be done in the current engine (which is bitmap only).

Ok, well, that's the end of the discussion for now.

But you did see what I was getting at, right ? It made sense ? If you've ever used Harmony's off the pegs system I think what I'm proposing should be clear. It exactly mimics how off pegs inbetweening was done on paper. I'm not interested in switching over to Harmony , but I have used it a little bit recently helping out on a short project and noticed how easy it was to use the off the pegs inbetweening function in Harmony, so I thought it would be worth asking if it were possible to do something similar in TVPaint.