Question about Sequential Key Framing

[garrick]

Hi, I've been trying to figure how to do a video like the one of the cat in varying poses (http://www.synthetik.com/blog/Site/Blog/68DEB9E4-9805-447A-9993-AD3B489FEE0A.html) but am struggling to figure exactly how. I have read the explanation many times but cannot seem to recreate it no matter how many times I try. I would be extremely grateful if anyone might help. Please forgive my lack of expertise. It is not for want of trying. You see, I'm a writer and teacher, not a computer person but I am, if anything, patient. Thank you so much to anyone out there! Garrick

[Synthetik]

There are a number of different approaches you can take to create something like the cat animation. I'm going to describe an approach here that mirrors the approach taken in the Vectorized Paint Tween Animation video tutorials on SA 3.5 tutorial disk #2, so if you watch those 3 tutorial videos i think that will help you understand what i'm going to describe below.. You could also do this style of animation by encapsulating the bezier paths in a single autopaint PASeq action step, but that's probably a little more involved to understand if you are just getting started.

The animation was created from a series of manual drawing of different cat poses. So first you would put together the image sequence you are interested in (unless you are free-drawing everything without the use of any source photos). I worked off of the source photo sequence so that i could use the onion skin capabilities.

So you would open the first source image. Then you can use the canvas : onion skin : toggle on/off menu to turn the onion skin on or off. You want a source onion in this case, so you'd switch to that if you had it set up to one of the other options.

Then, if you want your manually drawn paint strokes to be recorded as vector paths in the layer's current bezier path frame, you need to make sure the path : path layer record options : mouse draw menu flag is turned on. When this menu flag is turned on then every manual paint stroke you draw gets converted into a bezier path and saved in the bezier path frame after the drawing of the stroke is completed. You need to be aware that the bezier conversion code does not deal with non-contiguous paths very well, so the conversion process will fail if you have path randomize settings turned on. So you should use paint presets that are not using path randomization if you want to do this style of bezier animation.

Then you draw your sketch. You can draw as many paint strokes as you want for each source image you work with. When you are done with your sketch, in SA 3.5 you can option click the appropriate bezier keyframe in hte layer timeline that you want to store the bezier paths associated with the free sketch you created in. When you do this the keyframe should turn red.

When you move to your next keyframe source image to start your next free sketch, you will need to erase the existing bezier path frame as well as the raster paint canvas. In SA 3.5 the leftmost eraser button at the top right corner of the canvas does a full erase, so it erases the bezier path frame as well as sets the canvas to the default background setting (the popup next to it).

You then draw your next free sketch, record the bezier keyframe, etc. until you have recorded all of your bezier keyframes. So now you have a series of recorded bezier keyframes. You want to have a series of blank frames between each keyframe so you have a certain # of frames for the various poses to transform in. You could have recorded your keyframes with the spacing you want. Often i record contiguous keyframes with no spacing to make things easy when drawing and then add the spacing after the fact. You can use the canvas : layer timeline commands : time expand all timelines menu command to stretch out your timelines adding spaces between existing keyframes in SA 3.5.

At this point it's probably worth running the recorded animation to see what you are initially working with. Studio Artist interpolates between the bezier paths recorded in the bezier keyframes by their storage index in the recorded keyframe. So if one keyframe has 5 paths and the second keyframe has 15 paths then only 5 paths will be interpolated and the last 10 indexed paths in the second keyframe will be ignored until the animation timing gets to that specific keyframe.

Now if you look at the cat animation you will see that is not what happens. The drawn paths split apart so that there is full interpolation of the drawings, as opposed to sets of paths jumping into existence when keyframes at reached (what would happen when you initially run the animation after recording the keyframes).

There are some menu commands that let you normalize the number of paths in a set of keyframes so that all of the keyframes will have the same number of paths. you can recycle paths (they get duplicated), or split paths (they get split in half). If you look in the layers : layer timeline commands menu you will see those 2 normalize all bezier keyframe curve count menus. I used the split option for the cat animation.

Again, bezier paths are interpolated based on their storage index in the keyframe. So the paths will initially be interpolated in the order you draw them in. So if you were clever when drawing and always draw the same # of paths in each keyframe, then you would have full control over which paths interpolate to which. But this is hard to do when you are drawing free sketches with arbitrary numbers of paint strokes. However, there are also menu commands to let you reorder the recorded bezier paths so that they are reordered so that paths in adjacent keyframes that are spatially close to one another will be re-indexed so they have the same storage index and will then interpolated between each other in an animation. that's the reorder all bezier keyframe curves - minimal distance menu in layer timeline commands.

So first you run the normalize keyframe curves menu command, and then the reorder keyframe curves menu command. After doing this you will have a set of bezier keyframes and associated bezier paths that smoothly animate.

As far as running the animation, again there are a number of different ways you could do that. In SA 3.5 you could use the paint animation timeline animation operation mode. Action : Generate Frames : Run Paint Animation menu command will run this for you. Or you could record a PASeq that uses the Path : Paint Paths : Full Layer menu command recorded as an action step.

If you are recording a PASeq, you would probably want to record a set background initial action step to erase the canvas before drawing in the bezier paths. Or you could build a PASeq that fades and feathers the previous drawn frame if you want to get a little more sophisticated. If you are using the paint animation timeline animation op mode, then there's a checkbox in that control panel that you can turn on to redraw background each frame to do the erasing for you automatically.

Once you get the animation working the way you want it to, you could then run it while you had a movie stream open and it would be recorded into the open movie stream.


There are menu commands similar to what i describe above for PASeq action steps as well. these commands normalize or reindex bezier paths embedded within the action steps in a paseq. the paint synthesizer has an internal bezier path memory, so you can record a set of bezier paths in that internal path memory and they are stored in each autopaint paseq action step. so you could do what i describe above using paseq paint action steps. just a single paseq action step with a series of keyframes is enough to build the complete animation as i describe above. the advantage of using PASeq to do the animation is that you can break up sketch features into specific chunks (for even smoother interpolation), or you can use different paint presets for different parts of the sketch.

Note that i didn't use any of the PASeq sequential keyframe record features in my instructions above. I think it's probably conceptually easier to get a handle on what i described above before trying it that way. I'll do another post here that talks about the PASeq approach more later, but i did want to get an initial answer up quickly for you. The sequential keyframe record features can let you work quicker after you understand the basic ideas that are being used to generate this style of animation, but they aren't necessary to generate this style animation.

Version 4 gets rid of the dual layer and PASeq timelines and just uses a single PASeq timeline that lets you do everything. Version 4 has PASeq contexts that let you do everything you could do in the old SA 3.5 layer timeline in a PASeq. So doing this kind of animation is easier in version 4. More on that later as well.

[garrick]

Thank you so much for the prompt reply. I'll try this tomorrow and send you any questions that come up. Again, much appreciated!

[Synthetik]

Here's an old blog entry that talks about the vectorizer transition tutorial example and the use of the layer timeline commands to normalize and reindex the bezier curves.

If you want to have extreme control over every paint stroke and what it transforms to then you could record each individual paint stroke as a separate action step in a PASeq. This is where the sequential keyframe recording is helpful. So, you'd turn on PASeq recording and paint the first set of strokes for the first source image. Then, you'd load your next source image. Then you'd turn on the seq keyframe checkbox in the PASeq palette (keeping the rec button on). Then if you mouse down in the first action step's keyframe you want to record it turns selected, which means it's waiting for you to draw the new paint stroke for the keyframe. After drawing the paint stroke the selection moved down to the next action step's keyframe at that frame time and that keyframe is highlighted. So, you can record your new drawing without having to option click each new keyframe to record it. The recording and movement to the next keyframe happens automatically when using the sequential keyframe feature. When the selection moves to the next action step after you hand draw a stroke in seq keyframe recording, the paint preset will adjust itself automatically if you used different paint presets for the different paint strokes. Again, this is a huge time saver over having to do that manually.

After you complete all the keyframes associated with a specific frame time in seq keyframe recording the selection goes away. You can then press the mouse on the next top keyframe time you want to start recording at and run through drawing a complete set of new paint strokes again for your next frame time drawing.

[garrick]

John,
I have completed a very rudimentary version of the cat example! Thank you!! I'm slowly starting to understand some of the basics. I do have some questions before I tackle the PAS suggestions (I attempted them but was very confused). First, when you did the cats, did you draw each line manually on the onion skin? The bezier drawings of the cat are fairly precise, whereas my lines are quite clunky. I didn't know if this was a result of choices in the program (mouse vs. autodraw), artistic ability or equipment. I am using a mouse and was wondering if I should be using a tablet for greater precision. Or maybe I can auto draw the figure and have it record bezier lines. Or perhaps there is a way to make the picture bigger so the manual strokes on the onion skin would be less reckless? Would you suggest investing in a pen/tablet Wacom product? If the latter, what do you recommend? Do you have any suggestions for what preset is good for autopainting bezier paths?
Thanks,
Garrick

[Synthetik]

I did draw each line manually using the onion skin as a reference. I just used a simple black pencil preset to do the drawing. I'm not very good at manual drawing, so the onion skin is a key to getting a good representation result for me. I knocked the drawings off very quickly.

I did use a wacom tablet. Drawing is pretty clunky with a mouse vs using a pen and tablet. I like the intuos tablets for use with studio artist since they have tilt and tilt orientation modulation as well as pressure. If you are on a really budget then they have cheaper ones that just do pressure. I use a 6x8 tablet since it fits on my desk work area, travels well, and i'm comfortable with the scale of movement i use on it to cover the screen. The size is really a personal preference, some people are more comfortable with a larger range of motion (or smaller).

You could work with a larger canvas size if you are more comfortable doing the drawings at that size. And then after generating the animated movie, you could resize it in a second pass through studio artist to you final smaller size. This is also a way to get smoother line form if you want that since the canvas is anti-aliased as it is size reduced.

[garrick]

John,
So I've slowly started to recreate this effect and have some (probably simplistic) questions. So I have a series of images that-- through using the onion skin --have made into line drawings. As I've manually completed the line drawings (I'm using the preset Fine Sketch 2), I've also made sure that the mouse draw option is selected so that Bezier strokes are recorded along with Vector strokes. So far (I believe) so good. The problem I don't understand right now is that when I'm done with the line drawing, I option click on the layer timeline. However, when I erase (using the left most erase on the upper right hand corner) and go to the next drawing, do that line drawing and then option click a red keyframe into the timeline (let's say, ten frames away), the first line drawing does not appear if I go back and click on that first keyframe. This is just my inexperience but words of advice would be much appreciated! Should I be making multiple layers for each image?
Thanks,
Garrick

[Synthetik]

If you are recording bezier keyframes in the layer timeline then clicking on one of them after you recorded it would set the current bezier path frame to the recorded bezier curves. It would not draw a paint path using the paint synthesizer. It just resets the bezier path frame with the bezier curves. If you switch to bezier edit operation mode and then click on the bezier keyframes you can see what was recorded and how they interpolate if you click on an empty keyframe cell between 2 recorded keyframes.

To paint the current bezier path frame bezier curves with the current paint preset you can use the path : paint paths : full layer menu command.

You would have to record paint strokes as PASeq action step keyframes if you wanted to to record paint strokes that playback when you click a keyframe.

[Donna Kuhn]

all i can say is that i have tried that one several times and just couldnt get it either!

[liveart]

So when do we get to use V4 and all its wonderful new toys?