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be read by the program getinfo.
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2. Scene Description
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A scene description file represents a three-dimensional
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physical environment in Cartesian (rectilinear) world coor-
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dinates. It is stored as ascii text, with the following
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basic format:
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# comment
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modifier type identifier
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n S1 S2 S3 ... Sn
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0
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m R1 R2 R3 ... Rm
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! command
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...
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A comment line begins with a pound sign, `#'.
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The scene description primitives all have the same gen-
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eral format, and can be either surfaces or modifiers. A
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primitive has a modifier, a type, and an identifier. A
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modifier is either the identifier of a previously defined
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primitive, or void. An identifier can be any string (ie.
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sequence of non-blank characters). The arguments associated
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with a primitive can be strings or real numbers. The first
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integer following the identifier is the number of string
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arguments, and it is followed by the arguments themselves.
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The next integer is the number of integer arguments, and is
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followed by the integer arguments. (There are currently no
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primitives that use them, however.) The next integer is the
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real argument count, and it is followed by the real argu-
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ments.
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A line beginning with an exclamation point, `!', is
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interpreted as a command. It is executed by the shell, and
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its output is read as input to the program. The command
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must not try to read from its standard input, or confusion
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will result.
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Blank space is generally ignored, except as a separa-
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tor. The exception is the newline character after a command
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or comment. Commands, comments and primitives may appear in
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any combination, so long as they are not intermingled.
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2.1. Primitive Types
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Primitives can be surfaces, materials, textures or pat-
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terns. Materials modify surfaces, textures and patterns
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modify textures, patterns and materials.
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2.1.1. Surfaces
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A scene description will consist mostly of surfaces.
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The basic types are given below.
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