Key Framed Animation Part 5

Please be sure to review Key Framed Animation – Part 1 and Key Framed Animation – Part 2 and Key Framed Animation - Part 3 and Key Framed Animation - Part 4 before you continue with this final part of this series. You can also review the demonstration scene .

In Part 3 we constructed the underwater environment for our demonstration scene. In Part 4 we created the swimming cycle for our fish and we animated his swimming into the scene using a motion guide. The storyline calls for Filbert, the fish, to tread water briefly after he reaches mid-scene before he reacts to seeing the shark. To accentuate the surprise factor of this scene we have determined in the storyboards that animating the camera is appropriate at this time. In a cinematic scene we may stay within a common setting but the use of multiple shots or view points is useful in adding to the storytelling. We are going to move in close on Filbert before he reacts and then after his reaction fills the screen, we will “hard cut” back to a reveal shot of the source of his panic.

In order to animate the camera we need to attach the camera element to a peg element, the easiest way to do that is to use the “add parent peg” icon at the top of the timeline track label list while we have the camera element’s track selected. Once the camera is attached to a parent peg, which is named Camera-P a standard naming convention for a single element parent peg, we need to go to frame 1 of Camera -P and make the transform tool active and set our initializing keyframe. This is to lock down our starting characteristics for the camera. It is always a good practice to set a transform group of keyframes on the first frame of any peg to initialize the peg. This is true for separate peg elements or integrated pegs on image or drawing elements. Next we will move to frame 671 on the Camera-P peg and add a second key frame being sure the transform tool is still active. Again prior to starting a camera move it is advised to lock down the end of any previous shot. We will start out trucking in shot on frame 672. We need to make the motion tool active and set a motion keyframe. The camera’s point of view at frame 672 is the beginning of our trucking shot.

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Next we need to move to the ending frame of the shot at frame 710. With the motion tool still active we need to set a key frame. Now we can execute the shot by selecting the end of the motion path at frame 710 and dragging it to position our camera view point to the ending view of this shot. I usually do this in Top view first while visually watching the view point change in Camera view. I may, and usually do, make additional adjustments by dragging the end of the motion guide in the Side view as well.

Now that I have "trucked in" to the ending position of this shot, I need to go back to frame 672, the beginning position and on the Camera-P peg, I want to set the segment between frames 672’s motion key and frame 710’s motion key to be a non-constant segment. I set my TBS preferences to always create constant segments on my pegs as I prefer to set my non-constant segments manually when needed. Be sure you still have the motion tool active when setting this segment to tell TBS you are setting a motion key segment. The solid line between the motion keyframes indicates the segment is now a non-constant segment.

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Below you can see the motion paths with their corresponding spacing indicated in both the Side and Top view panels. I left the velocity function as the default even spacing because this is a really short duration move and it works well that way. Had it been a longer move I probably would have used an ease-in ease-out velocity function.

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Filbert's screaming reaction starts at frame 723. I animated this similarly to the way I animated his swimming cycle in drawing view by drawing the various cells to create the scream. So now I just need to insert that element and these cells into the timeline starting with frame 723. I need to be sure to have the select tool active before I start trying to position this Filbert screaming element. The hardest part of keyframe animation is making sure you always have the best tool selected for what you are trying to do. You have to be paying attention to your active tool or you can make inadvertent mistakes really easily.

The shark is also animated as an element in drawing view and I have placed his swimming cycle into the time line but he is currently off camera because we are still "trucked" in tight on Filbert.

At frame 770 on the Camera-P peg I want to set a new motion key, so I have to make the motion tool active. I add a keyframe and reposition the camera’s view point to the "reveal" of the shark. I want this camera shot to be a “hard cut” so I will leave the segment between frame 710’s motion key and frame 770’s motion key as a constant segment.

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This causes the shot to “snap” from the "trucked in" close up to the reveal shot when the movie reaches frame 770

Now it is time to have Filbert make a strategic retreat. Actually he is going to “zip” out of there for his life!! Things will happen so fast that I can save myself a lot of work by just reusing the same swim cycle I used earlier in the scene. I made it a template, so reusing it is just a matter or dragging and dropping it from my library to the timeline.

It is just one 12 frame cycle. Now you might be wondering why I used a second instance of the swimming template rather than adding to the time line of the first instance I used at the beginning of the scene. That instance has static values I applied to it to position and flip the fish. If I just advance the timeline for that instance and repositioned Filbert with the scene planning select tool so that he was facing the opposite direction it would be a global change and mess up the first bit of animation I made. It is just cleaner and easier to reuse the template as a new series of tracks just for this short “zip” off.

So, I place Filbert swimming into the scene starting at frame 795. I use the select tool to scale him to 50% but I don’t need to flip him horizontally this time. Using the transform tool I put a starting and ending keyframe on his main character peg just for good measure and I selected the 12 frames with the main character peg collapsed and copied them. I moved to the end of the cycle and pasted them using “paste special” to extend the exposure of the first cycle to a second cycle. This second cycle will totally never be seen but I wanted the extra frames to help with my “zip” motion. Now I will attach the second instance of Filbert swimming to a peg element which I added and named “Zipaway”. This is going to be my motion guide. I collapse the Zipaway peg and make the motion tool active and go to frame 795 on the Zipaway peg and set a motion key. I then move to frame 819 on the Zipaway peg and set a second motion key. I move the motion guide's end to position Filbert off screen using the Top view and Side view to get the desired location. Then I return to frame 795 on the Zipaway peg and with the motion tool active, set the segment between these two motion keys to be a non-constant segment.

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I want the spacing for this "zip" action to be different from the default even spacing, so I need to create a different velocity curve from the default linear velocity curve.

With the “Zipaway” peg selected in the timeline, I open the function editor; I have the function editor set up as keyboard short cut key “J” which makes opening and closing the panel really convenient. I first need to select "velocity" as my function because this is a motion segment. If it had been a scale segment I would have chosen H-scale or V-scale, for a rotation segment I would have chosen Rotation, and for a skew segment I would have chosen Skewing. They are all used to set the spacing for the “tweening” just for different attribute types. I zoom in on my frames for this segment and using the "reshape" pull down at the top right corner of the function editor window, I chose a fast out/in curve shape. I’m not interested in the end of the motion’s spacing because it will be off camera, but the beginning spacing is important to getting the desired action. I want the in betweens to be farther apart as the beginning to add speed to the action.

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I added a special effect with bubbles in element " Bubbles 3" to give the "zip" an extra impact as Filbert is really stirring up the water as he makes for cover. That’s pretty much it for this scene. I certainly hope that this series on Key Framed Animation has given you a sound foundation on keyframing and how to use this technique in animating. There are plenty of additional aspects to key framed animation but those are for future articles.

Above is a view of the track label list with pegs mostly collapsed but I wanted to show you the tracks that were the same template reused twice as well as the motion guide peg elements.

Key Framed Animation Part 2

In Part 1 we discussed the basics of key framed animation. In part 2 we will begin to discuss how key framed animation is implemented and controlled in Toon Boom Studio.

First we want to review some background concepts.

Pictures are composed of multiple picture elements

As we all discussed in It's Elemental Part 1, animation is created by rendering a series of pictures in a sequence and displaying those pictures at a sufficient rate of speed so as to generate the phenomena called “persistence of vision”. Basically our goal is to optically blend sequential images together to create the visual effect of continuous motion. The individual pictures themselves can be a single element or a combination of many picture elements. In most animations, the pictures in the sequence, also referred to as the frames in the sequence, are constructed as compositions of many layered picture elements. In traditional hand drawn animation, these picture elements are arranged in an overlapping layered stack under a rostrum camera for photographing.

Each picture element traditionally was created separately on a clear transparent plastic sheet called a cell. The stacking order of the cells creates the visual effect of depth by allowing some picture elements to overlap other picture elements producing perspective in a 2D picture. In order to position each picture element’s cell relative to the other elements of that composite picture, there is the need for some means of element registration. The accurate registration of picture elements to avoid unintentional shifting is critical because any variation in the positioning of a picture element photographed in successive frames of an animated sequence creates the illusion of motion. To accomplish this accurate positioning, a cell registration device had to be invented, and thus the registration peg and the registration peg bar were created. By punching registration holes in each cell that matched the registration peg pins of the peg bar, it was possible to insure accurate positioning of each and every drawing element in the layered composition stack for each photographed frame of the animation. Additionally by utilizing multiple peg bars, some which were held stationary and some which could be incrementally repositioned, it became possible to create the illusion of motion by simple frame by frame repositioning of selected image elements. These incrementally movable peg bars became known as traveling peg bars.

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Besides having multiple traveling peg bars, a photographic animation camera stand also has an incrementally movable picture composition surface, the picture plane, that is capable of producing compound movements in all horizontal directions (North, South, East and West) including 360 degree rotational movements. The creation of the multi-plane camera stand, by the addition of multiple picture composition planes, provides additional photographic depth between picture elements. Traveling peg bars in conjunction with the compound directional movements of the picture planes of the camera stand are the ancestors of Toon Boom Studios peg element motion guides .

Pegs

So as we discussed in Part 1, we can direct computer aided animation using keyframes but we need a way to connect an element to many different types of keyed frame values as well as a way to specify the length of our connecting segments between each beginning and ending keyed frame pair. We also need a place to tie a velocity function curve to each connecting segment. In Toon Boom Studio we have a container for keyed frame values and inbetweening instructions and that container is called a peg. Looking back to the origin of the registration peg, we can see that pegs and peg bars were originally created as registration devices, and we are still using them in that way in our virtual version too. We are registering animation attribute values and instructions to art work elements for specified frame sequences.

In Toon Boom Studio beginning with version 3.5, we can have pegs in two forms. We can have them as independent element tracks in our timeline or we can have them as integrated parts of other element tracks where the peg is included inside of a drawing or image element track. The important point here is that any usage of pegs for containing information and instructional registration is a part of compositing and planning and therefore only useful in the timeline directly associating the pegs with Camera View for scene planning. Pegs have no real meaning with respect to the exposure sheet which is primarily used to manage drawing organization and Drawing View. Don’t forget to review It’s Elemental Part 2 for more information on the uses of the exposure sheet and the timeline panel.

A peg, whether an independent element or integrated into a drawing or image element, can contain multiple different types of attributes of keyed frame values at each individual frame in a scene (location, scale, rotation, or skew values). TBS provides specific visual indicators on a timeline track display for each type of keyed value present at each single frame. Conceptually a peg element is a collection of pegs, each of which is a multi-valued container. Each frame position of a peg element is a peg container. For simplification we just refer to the peg element and its individual peg containers as a peg. So just like the term keyframe can be singular or plural depending on the context of our use, the same thing is true for the term peg. And a peg element can contain many connecting segments as defined by each occurrence of a starting and ending key framed value for the same type of attribute. This means that even though three segments, one for scale and one for rotation and one for location, might all start at the same frame they don’t have to be the same length, they can each end on different frames. Each segment does not have to have the same type of inbetweening method either, some could be constant and the others non-constant, and each non-constant segment has its own unique velocity function curve that controls the in between image spacing. That’s a lot of flexibility for us as animators to be able to direct.

As we learned in Part 1, key framed animation is a form of programming instructions. But in TBS we don’t write code to direct the render engine, we do it using visual tools like the scene planning tools and the function editor and the pegs themselves. How we use these visual aids dramatically effects how well we function as lead animators. So the more we understand about how they work and their interactions, the easier and more successful our directing tasks. Yes, we are animating but we are also directing the render engine and it requires significant skill and experience to do this correctly. After all we have to be the lead animator and the render engine is our obedient inbetweening assistant. That assistant does exactly what we instruct it to do, even if we inadvertently give it incorrect instructions. So it is easy to be lulled into thinking that key framed animation is really simple due to the fact that we do things visually and not by typing script code in TBS. But when you consider how detailed and complicated the directions can be which you are trying to communicate to your assistant, the render engine, you can begin to appreciate that this is not a trivial task.

Scene planning tools

Scene planning tools are used to specify or address the type or types of attributes with which you want to work. They are more than visual manipulators, they are specific selection switches. When you select a scene planning tool from your tool pallet it becomes active and it limits what type of instructions you can influence. Once a scene planning tool has been chosen you can only create, edit, copy or delete the associated type or types of attributes of keys for that specific tool. When the transform tool is active it is used as an all purpose keying tool as it addresses location, rotation, scale and skew attributes all at the same time. When the scale tool is active it only addresses scale attribute values. When the rotation tool is active it only addresses rotation attribute values. When the skew tool is active it only addresses skew attribute values. And when the motion tool is active it only addresses motion path attribute values. The scene planning selection tool doesn't address any keyed frame types at all when it is active. But it still has an very important instructional purpose which we will learn more about in Part 3.

Each matching keyed type of attribute can be viewed as part of a pair of keyframes which is connected by an inbetweening instructional segment. Each segment is created as either a constant segment or a non-constant segment. For the same element there can be multiple types of attributes keyframed and the connecting segments for each keyframe pair of common attributes can be set independently. The way a particular keyed frame attribute is specifically addressed is by the scene planning tool you select to be active. So if you only want to address a rotation pair of keyframes you would select the rotation tool to be active. Or, if you only wanted to address a scale pair of keyframes you would select the scale tool to be active. The important concept to remember when working with keyed frame attributes is that the scene planning tool you select to be active dictates which attributes you are addressing when you are creating, editing, copying or deleting keyframes or their connecting segments. We will get into more detail about this in part 3 on Key Framed Animation.

So to extend what we have learned so far, pegs are used to keyframe animate objects across time. You can attach one or more elements to a peg and you can attach pegs to other pegs to create complex hierarchies of control. Pegs are used to facilitate computer rendered inbetweening. So when you have elements attached to a peg, you can set keyframes and TBS interpolates inbetween those keyframes based on the values of those keyframes and the type of connecting segment used. And you can use velocity function curves to adjust the way the inbetweening is applied which is often called “custom easing” or "cushioning". Basically the curve specifies the rate of change between the images, their spacing.

Additionally, pegs can be controlled by motion paths which are 3D and those motion paths can have adjustable keyframes and they also can have frame independent motion control points. That allows you to have some motion control that has to happen at a specific point in time and other motion controls that are 3D space dependent and not time dependent. At this point, you should begin to see that TBS has some very sophisticated functionality that can provide a lot of flexibility for us as animators once we master the skills of directing this method of communicating instructions to the render engine.

There is a new way to use pegs in v3.5 as each image or drawing element now includes a peg as part of that image or drawing element. This means that keyframing does not require attaching elements to separate peg elements as was the case in previous TBS versions. Of course the power and flexibility of separate peg elements still exists and so this new creation of integrated peg elements is not just a simplification but is also an enhancement.

Each type of attribute of keyed frame value can be set uniquely using their own special scene planning tool. Some people misunderstand the flexibility and power of this approach. You can use the transform tool for rough keyframing and then when you go to tweak an animation action you can use the individual scene planning tools to fine tune it and not accidentally mess up other types of keyed frame attributes. Because you can individually address key framed values with specific scene planning tools on the same frame, you can selectively delete those types of key framed parameters without deleting other types of keyframed values that you want to maintain on that same frame.

So in Part 3 of Key Framed Animation we will begin to look at the ways to actually use the scene planning tools and pegs and keyframes and velocity curves.