C H A P T E R 2

LaserWriter Select 310 Software

packedarray

Syntax

any0...anyn-1packedarray packedarray

Definition

This operator creates a packed array object of length n. The array object

 

contains the objects any0 through anyn-1as elements. The packed array

 

operator first removes the non-negative integer n from the operand stack,

 

creates a packed array containing those objects as elements, and finally

 

pushes the resulting packed array object onto the operand stack.

 

The resulting object has a type of packedarraytype, a literal attribute,

 

and read-only access. In all other respects, its behavior is identical to that

 

of an ordinary array object.

Error

rangecheck, stackunderflow, typecheck, VMerror

setcacheparams

Syntax

mark lower upper setcacheparams -

Definition This operator sets cache parameters as specified by the integer objects above the topmost mark on the stack, and then removes all operands and the mark object as if by cleartomark.

The number of cache parameters is variable. If more operands are supplied to setcacheparams than are needed, the topmost ones are used and the remainder ignored. If fewer are supplied than are needed, setcacheparams implicitly inserts default values between the mark and the first operand supplied.

The upper operand specifies the maximum number of bytes that may be occupied by the pixel array of a single cached character. The lower operand specifies the threshold at which characters are stored in compressed form rather than as full pixel arrays. If a character’s pixel array requires more bytes than specified by lower bytes to represent it, it is compressed in the cache and reconstituted from the compressed representation each time it is needed.

Setting lower to zero forces all characters to be compressed, permitting more characters to be stored in the cache, but increasing the amount of work required to print them. Setting lower to a greater value than upper disables compression.

Errors rangecheck, unmatchedmark

Setting Compatibility Operators

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Apple 310 manual Packedarray, Setcacheparams