Datasheet

The number of frames that are played back per second determines the frame rate of an
animation. This is denoted as fps, or frames per second. The three standard frame rates for
media are:
• NTSC: 30fps
• PAL: 25fps
• Film: 24fps
Knowing what your final output medium is going to be before you begin your project
is pretty important. It is not crucial by any means, but knowing what the screen will look
like (i.e., whether it will be a small web window or a large television) will help you better
compose your scenes. You can always change your frame rate and render resolution later,
but it is much simpler to begin with it already worked out.
Playing back a 24fps animation at 30fps will yield a slower-moving animation and will
either require repeating some frames to fill in the gaps or ending the animation early.
Conversely, playing a 30fps animation at 24fps will create a faster-moving animation that
will either skip some frames or end later than it should.
Games do not typically have a set playback rate for animation. When a scene is created
for a game, the assets in the scene are rendered and played back on the user’s computer
system in real time; therefore, many factors contribute to the playback speed of scenes
created for games.
On the Internet, typical playback speeds for animated content on websites average
about 12 to 15 frames per second, about half of what you would see on a TV or film
screen. This saves the viewer considerable download time because the files are much
smaller.
Coordinate Systems
Coordinates are numerical representations of where an object is in 3D space. Every object
in 3ds Max has a coordinate of where it exists. Without this coordinate, it would be gone—
poof—into thin air! Max’s 3D space is organized with the Cartesian coordinate system,
which uses a three-pronged axis to define width, height, and depth as X, Y, and Z, respec-
tively. The overall coordinate system in Max is called the world coordinate system. It is an
absolute coordinate system that is fixed and unchangeable.
Objects in Max can have their own coordinate systems as well. When an object is created,
it has its own width, height, and depth, again expressed as X, Y, and Z. Upon creation, the
local coordinate system (belonging to the created object) and the world coordinate system
are aligned. However, when the object is rotated, its Local Coordinate System rotates with
it. Because of this, an object created in a Front viewport (for instance) will have a different
Local axis than if it were created in the Top viewport.
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