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This means that a keyframe is set or modified each time that you change the position of a Deform pin. This is unlike most properties in After Effects, for which you must explicitly set the stopwatch switch by adding a keyframe or an expression to animate each property. The auto-animation of Deform pins makes it convenient to add them and animate them in the Composition panel or Layer panel, without manipulating the properties in the Timeline panel.
1 Select the layer that contains the image to animate.
2 Using the Puppet Pin tool, do one of the following in the Composition panel or the Layer panel:
• Click any nontransparent pixel of a raster layer to apply the Puppet effect and create a mesh for the outline created by auto-tracing the layer’s alpha channel.
• Click within a closed path on a vector layer to apply the Puppet effect and create a mesh for the outline defined by that path.
• Click within a closed, unlocked mask to apply the Puppet effect and create a mesh for the outline defined by the mask path.
• Click outside all closed paths on a vector layer to apply the Puppet effect without creating a mesh. Outlines are created for paths on the layer, though an outline is only visible when a Puppet tool pointer is over the area that the outline defines. Place the pointer over the area enclosed by a path to see the outline in which a mesh will be created if you click that point. (See “How the Puppet effect creates outlines” on page 230.) Click within an outline to create a mesh.
A Deform pin is placed where you clicked to create the mesh.
Note: If an image is too complex for the Puppet effect to generate a mesh with the current Triangle value, a “Mesh Generation Failed” message appears in the Info panel. Increase the Triangle value in the Tools panel and try again.
3 Click in one or more places within the outline to add more Deform pins.
Use as few pins as possible to achieve your desired result. The natural deformation provided by the Puppet effect can be lost if you over-constrain the image. Just add pins to the parts of the figure that you know that you want to control.
For example, when animating a person waving, add a pin to each foot to hold them to the ground, and add a pin to the waving hand.
4 Go to another time in the composition, and move the position of one or more of the Deform pins by dragging them in the Composition or Layer panel with the Puppet Pin tool. Repeat this step until you have completed your animation.
You can modify the Deform pins’ motion paths as you would any other motion paths.
AFTER EFFECTS CS3 229 User Guide See also “Work with pins and the distortion mesh” on page 231 “Creating and modifying motion paths” on page 197 Record animation by sketching motion with the Puppet Pin tool You can sketch the motion path of one or more Deform pins in real time—or at a speed that you specify—much as you can sketch the motion path of a layer using Motion Sketch.
If your composition contains audio, you can sketch motion in time with the audio.
Before you begin recording motion, you may want to configure settings for recording. To open the Puppet Record Options dialog box, click Record Options in the Tools panel.
Speed The ratio of the speed of the recorded motion to playback speed. If Speed is 100%, the motion is played back at the speed at which it was recorded. If Speed is greater than 100%, the motion plays back slower than it was recorded.
Smoothness Set this value higher to remove more extraneous keyframes from the motion path as it’s drawn.
Creating fewer keyframes makes motion smoother.
Use Draft Deformation The distorted outline that is shown during recording does not take Starch pins into account.
This can improve performance for a complex mesh.
Note: This procedure assumes that you have already placed Deform pins in the object to animate. For information on placing Deform pins, see “Manually animate an image with the Puppet tools” on page 228.
1 Select one or more Deform pins.
2 Go to the time at which to begin recording motion.
3 In the Composition panel or Layer panel, hold the Ctrl (Windows) or Command (Mac OS) key to activate the Puppet Sketch tool. Ctrl-drag (Windows) or Command-drag (Mac OS) the pins to animate.
Recording of motion begins when you click to begin the drag. Recording ends when you release the mouse button.
The color of the outline for the mesh for which motion is being sketched is the same as the color of the pin (yellow).
Reference outlines, for other meshes on the same layer, are the color of the layer’s label.
The current-time indicator returns to the time at which recording began, so that you can repeat the recording operation with more Deform pins or redo the recording operation with the same pins.
You can modify the Deform pins’ motion paths as you would any other motion paths. A pin’s motion path is shown only if it is the only pin selected.
Try creating several duplicate meshes and sketching motion for each mesh. When you have multiple meshes in the same instance of the Puppet effect, you can sketch motion for one mesh while seeing the reference outlines of the others, allowing you to follow their movements, either roughly or precisely.
How the Puppet effect creates outlines When a Puppet mesh is created, its boundaries are determined by an outline, which can be defined by any of the
following types of closed paths:
• An unlocked mask path
• A shape path on a shape layer
• A text character’s outline If a layer has no unlocked masks, shapes, or text characters on it when you apply the Puppet effect, it will use Autotrace to create paths from the alpha channel. These paths are only used by the Puppet effect in the determination of outlines and do not appear as masks on the layer. If the layer is a raster layer with no alpha channel, the result is a single rectangular path around the layer’s bounds. For a complex image, or to configure Auto-trace settings, use Auto-trace before using the Puppet tools. (See “Create a mask from a channel with Auto-trace” on page 256.) A text character that consists of multiple disjoint closed paths (such as the letter i) is treated as multiple separate paths.
A shape or character’s stroke is not used in the determination of outlines; only the path is used. To encompass a stroke within a mesh created from such items, increase the Expansion value. The default value of 3 pixels for Expansion encompasses a stroke that extends 3 pixels or less from its path.
Apply paint strokes to a layer using the Brush tool with the Paint On Transparent option. This creates a raster layer with only the paint strokes, defined by an alpha channel. You can then use the Puppet tools to animate the paint strokes. Do not use a mask on the layer.
If multiple masks, shapes, or characters overlap on the same layer, an outline is created from the union of the overlapping shapes, overlapping characters, or overlapping masks. If a mask overlaps a text character or shape, outlines are created for the entire character or shape, for the portion of the character or shape that is inside the mask, and for the mask itself.
To distort multiple disjoint characters or shapes as one object, surround the individual objects with a mask (with mask mode set to None), and use the mask path as the outline with which to create the mesh. You can delete the mask after you have created the mesh.
If the Puppet effect has already been applied to a layer, outlines appear with a yellow highlight as you move a Puppet tool pointer over them. You can choose the outline in which to place an initial pin to create a mesh. A mesh is created each time that you click within an outline with a Puppet tool.
If the Puppet effect has not already been applied to a layer, outlines for that layer have not yet been calculated. When you click, the Puppet effect calculates outlines and determines whether you have clicked within an outline. If so, it creates a mesh defined by the outline in which you clicked. Otherwise, you can move the pointer around the layer to select the outline in which to place a pin and create a mesh. This is very useful for seeing the outlines of various objects and choosing which outlines to use to create a mesh.
Work with pins and the distortion mesh
• To show the mesh for the Puppet effect, select Show in the options section of the Tools panel.
• To select or move a pin, click or drag it with the Move tool. To activate the Move tool, place the pointer on a pin while either the Selection tool or the corresponding Puppet tool is active.
• To select multiple pins, Shift-click them, or use the marquee-selection tool to drag a marquee-selection box around them. To activate the marquee-selection tool, place the pointer for a Puppet tool outside all meshes and outlines or hold the Alt (Windows) or Option (Mac OS) key.
• To select all pins of one kind (Deform, Starch, or Overlap), select one pin of that kind and press Ctrl+A (Windows) or Command+A (Mac OS).
• To delete selected pins, press the Delete key. If the pin has multiple keyframes, and only the keyframe at the current time is selected, pressing Delete will delete only that keyframe; pressing Delete again will delete the pin.
• To reset Deform pins to their original locations at the current time, click Reset for the Puppet effect in the Timeline panel or Effect Controls panel. To remove all pins and meshes from an instance of the Puppet effect, click Reset again.
Sometimes, you want to animate an image from an initial position, through an intermediate position, and back to the initial position. Rather than manually dragging the pins back to their initial positions at the end of the animation, place the current-time indicator at the end time and click Reset. Only the keyframes at the current time are reset.
• To increase or decrease the number of triangles used in a mesh, modify the Triangle value in the options section of the Tools panel or in the Timeline panel. This modifies the value for a selected mesh or, if no mesh is selected, sets the value for meshes created later.
A higher number of triangles gives smoother results but takes longer to render. Small objects, like text characters, usually distort well with only 50 triangles, whereas a large figure may require 500. The number of triangles used may not match the Triangle value exactly; this value is a target only.
• To expand the mesh beyond the original outline, increase the Expansion property in the options section of the Tools panel or in the Timeline panel. This modifies the value for a selected mesh or, if no mesh is selected, sets the value for meshes created later. Expanding the mesh is useful for encompassing a path’s stroke.
• To duplicate an object using Puppet Pin tool, click within the original outline. This creates a new mesh, with its own copy of the pixels from within the original outline. You can also duplicate a Mesh group in the Timeline panel to achieve the same result, which is sometimes easier than clicking within the original outline without clicking on the mesh to create a pin.
Overlap pin with positive In Front value (top), and Overlap pin with negative In Front value (bottom)
Each Overlap pin has the following properties:
In Front The apparent proximity to the viewer. The influence of Overlap pins is cumulative, meaning that the In Front values are added together for places on the mesh where extents overlap. You can use negative In Front values to cancel out the influence of another Overlap pin at a specific location.
Extent How far from the Overlap pin its influence extends. The influence ends abruptly; it does not decrease gradually with distance from the pin. Extent is indicated visually by a fill in the affected parts of the mesh. The fill is dark if In Front is negative; the fill is light if In Front is positive.
Unwanted distortion in figure (top left) is prevented with Starch pin (upper right and lower left)
Each Starch pin has the following properties:
Amount The strength of the stiffening agent. The influence of Starch pins is cumulative, meaning that the Amount values are added together for places on the mesh where extents overlap. You can use negative Amount values to cancel out the influence of another Starch pin at a specific location.
If you notice image tearing near a Deform pin, use a Starch pin with a very small Amount value (less than 0.1) near the Deform pin. Small Amount values are good for maintaining image integrity without introducing much rigidity.
Extent How far from the Starch pin its influence extends. The influence ends abruptly; it does not decrease gradually with distance from the pin. Extent is indicated visually by a pale fill in the affected parts of the mesh.
In addition to animating still images, you can use the Puppet effect on a layer with motion footage as its source. For example, you could distort the contents of the entire composition frame to match the motion of an object within the frame. In this case, consider creating a mesh for the entire layer, using the layer boundaries as the outline, and using the Puppet Starch tool around the edges to prevent the edges of the layer from distorting.
Chapter 9: Color
Color basics Set the color depth Color depth (or bit depth) is the number of bits per channel (bpc) used to represent the color of a pixel. The more bits for each RGB channel (red, green, and blue), the more colors can be represented.
In After Effects, you can work in 8-bpc, 16-bpc, or 32-bpc color.
In addition to bit depth, a separate characteristic of the numbers used to represent pixel values is whether the numbers are integers or floating-point numbers. Floating-point numbers can represent a larger range of numbers with the same number of bits. In After Effects, 32-bpc pixel values are floating-point values.