Continuously rasterize a layer containing vector, Graphics – Adobe After Effects CS4 User Manual
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USING AFTER EFFECTS CS4
Layers and properties
Last updated 12/21/2009
To toggle between Best and Draft quality of selected layers, click the Quality switch in the Timeline panel. To choose
from all three options, choose Layer
> Quality:
Best
Displays and renders a layer using subpixel positioning, anti-aliasing, 3D shading, and complete calculation of
any applied effects. Best requires the most time for rendering—both for previews and for final output.
Draft
Displays a layer so that you can see it, but only at rough quality. Draft quality displays and renders a layer without
anti-aliasing and subpixel positioning, and some effects are not precisely calculated.
Wireframe
Displays a layer as a box, without layer contents. Layer wireframes are displayed and rendered faster than
layers rendered with Best or Draft settings.
Subpixel positioning
Property values (like Position and Anchor Point) in After Effects are not restricted to integer values; they can have
fractional values, too. This allows for smooth animation, as a value is interpolated from one keyframe to another. For
example, if a Position value goes from [0,0,0] at a keyframe at time 0 to a value of [0,0,80] at time 1 second in a 25-
frames-per-second composition, then the value at frame 1 is [0,0,3.2].
After Effects calculates all spatial values, like Position and effect control points, to a precision of 1/65,536 of a pixel.
This is called subpixel precision.
If the pixels of a layer aren't positioned directly on the pixel boundaries of the composition, a small amount of blur
occurs—very similar to anti-aliasing. This blur is not a problem for an object in motion, because objects in motion
have motion blur, but it can soften fine details in a static image. Also, if an image is moving slowly or at just the wrong
speed, the image can appear to oscillate between sharpness and blurriness.
Because the default anchor point for a layer is the center of an object, odd-sized objects have non-integer anchor points
and appear soft when positioned at integer values. To minimize blurriness and in-and-out of focus result, follow these
guidelines:
•
Create graphics with odd or even dimensions, based on the dimensions of the composition. For example, if the
composition is 640x480 pixels, create graphics with even dimensions (such as 100x100 pixels); if the composition
is 99x99 pixels, create graphics with odd dimensions (such as 75x53 pixels).
•
Set the position information for graphics (including the hold position and final position keyframes) to integers and
not fractional numbers.
More Help topics
Layer switches and columns in the Timeline panel
Continuously rasterize a layer containing vector graphics
When you import vector graphics, After Effects automatically rasterizes them. However, if you want to scale a layer
that contains vector graphics above 100%, then you need to continuously rasterize the layer to maintain image quality.
You can continuously rasterize vector graphics in layers based on Illustrator, SWF, EPS, and PDF files. Continuously
rasterizing causes After Effects to rasterize the file as needed based on the transformation for each frame. A
continuously rasterized layer generally produces higher-quality results, but it may render more slowly.
Shape layers and text layers are always continuously rasterized.