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chapter five
Basic Computer Animation Techniques
syed ardi syed yahya kamal2011
chapter five
Principles of Keyframe Interpolation Creating in-between positions is still a
hallmark of animation. Using techniques called interpolation
computer animation software can create the in-between positions.
This is called keyframe interpolation, and it is an essential computer animation technique used in a myriad of ways to create sequences of still frames.
chapter five
Cont.. Keyframe interpolation calculates the
in-between frames by averaging the information specified in keyframes.
Interpolation techniques can be used to calculate the position of objects in space, as well as their shapes and other attributes.
The most common types of interpolation include linear and curve interpolation.
chapter five
Cont.. Establishing a keyframe is usually
done interactively, using an animation timeline that stores the position and duration of the different moments and actions being animated.
Interpolating keyframes allows us to control the time, or speed, that is takes to get from one keyframe to another and the rate of change between frame.
chapter five
Cont.. Interpolation is commonly expressed in
the form of a graph that shows the relation between time and the parameter being animated.
Time is usually represented by the horizontal axis and the parameter in question is usually represented by the vertical axis.
The slope of the path in the graph represents the speed or rate of change.
chapter five
Cont.. Interpolation graphs are generated
automatically by most computer animation software as soon as animator specifies the animation parameters on one or several objects in the scene.
It is usually possible to edit these graphs interactively.
chapter five
Linear Interpolation Linear interpolation is the simplest and
most straightforward computer animation technique for calculating in-between frames.
Linear interpolation simply averages the parameter in the keyframes and provides as many equally spaced in-between frames as needed.
chapter five
Cont.. Linear interpolation is based on
constant speeds between the keyframes.
Constant speed is represented by the straight lines in the graph.
Linear interpolations cannot handle subtle changes in speed because the in-between frames are created at equal intervals along the path.
chapter five
Curve Interpolation Also called interpolation ease, is a
techniques for calculating in-between frames that is more sophisticated than a linear interpolation.
Curved interpolation averages the parameter in the keyframes, taking into account the variations of speed over time, known as acceleration.
chapter five
Cont.. When curved interpolation is represented
in graphical form the increase in speed, also called an ease in, is represented by a line that curves up.
An ease out, or decrease in speed, is represented by a line that curves down.
Therefore, the distribution of in-between frames along the path depends on whether the rate of change increases or decreases.
chapter five
Getting Ready For Animate Choose Appropriate Motion
Audience learn a lot about the emotions and intentions of animated characters by the way they move.
Make sure that the motion applied to the models matches the dramatic purpose of the scene.
chapter five
Cont.. Avoid Still First Frames
One or several still frames at the beginning of an animated sequence usually look like a mistake, as if when the camera starts rolling before the actors are ready.
chapter five
Cont.. Preview the Motion
Virtually all computer animation programs allow for the creation of motion flipbooks that can be played back directly onto the computer screen.
Before digital flipbooks are available, motion test could only be previewed by recording each frame onto a videotape , and playing them back on videotape player.
Those days are fortunately gone
chapter five
Cont.. Check the Preference File
Setting the preferences for file including the animation rate of frames per second, the aspect ratio of the still image and whether to load external files.
This will affect the final look of the animation project.
chapter five
Cont.. Follow the Animatic or Storyboard
When animating it is important to stick to the directions specified in the animatic or storyboard because other individuals may be working at the same time on the same sequence as you are.
chapter five
End of Chapter 5syed ardi bin syed yahya kamal
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