ImagerTypeface.mesa
Copyright © 1985 by Xerox Corporation. All rights reserved.
Doug Wyatt, November 11, 1985 4:47:33 pm PST
Michael Plass, February 25, 1986 3:33:26 pm PST
DIRECTORY
Basics,
Imager USING [Context],
ImagerFont,
Rope USING [ROPE],
Vector2 USING [VEC];
ImagerTypeface: CEDAR DEFINITIONS
~ BEGIN
VEC: TYPE ~ Vector2.VEC;
ROPE: TYPE ~ Rope.ROPE;
BYTE: TYPE ~ Basics.BYTE;
XChar: TYPE ~ ImagerFont.XChar;
Version: TYPE ~ ImagerFont.Version;
CorrectionType: TYPE ~ ImagerFont.CorrectionType;
Extents: TYPE ~ ImagerFont.Extents;
Typeface: TYPE ~ REF TypefaceRep;
TypefaceRep:
TYPE ~
RECORD [
class: TypefaceClass,
data: REF
];
TypefaceClass: TYPE ~ REF TypefaceClassRep;
TypefaceClassRep:
TYPE ~
RECORD [
FullName: PROC [self: Typeface] RETURNS [ROPE],
Contains: PROC [self: Typeface, char: XChar] RETURNS [BOOL],
NextChar: PROC [self: Typeface, char: XChar] RETURNS [next: XChar],
Escapement: PROC [self: Typeface, char: XChar] RETURNS [VEC],
Amplified: PROC [self: Typeface, char: XChar] RETURNS [BOOL],
Correction: PROC [self: Typeface, char: XChar] RETURNS [CorrectionType],
BoundingBox: PROC [self: Typeface, char: XChar] RETURNS [Extents],
FontBoundingBox: PROC [self: Typeface] RETURNS [Extents],
Ligature: PROC [self: Typeface, char, successor: XChar] RETURNS [XChar],
NextLigature: PROC [self: Typeface, char, successor: XChar] RETURNS [XChar],
Kern: PROC [self: Typeface, char, successor: XChar] RETURNS [VEC],
NextKern: PROC [self: Typeface, char, successor: XChar] RETURNS [XChar],
Mask: PROC [self: Typeface, char: XChar, context: Imager.Context]
];
Masks: TYPE ~ REF MasksRep;
MasksRep:
TYPE ~
RECORD [
class: MasksClass,
data: REF,
name: ROPE,
version: Version
];
MasksClass: TYPE ~ REF MasksClassRep;
MasksClassRep:
TYPE ~
RECORD [
type: ATOM,
Path: PROC [self: Masks, char: XChar, moveTo: ImagerPath.MoveToProc,
lineTo: ImagerPath.LineToProc, curveTo: ImagerPath.CurveToProc,
conicTo: ImagerPath.ConicToProc, arcTo: ImagerPath.ArcToProc],
Mask: PROC [self: Masks, char: XChar, context: Imager.Context]
];
Creator: TYPE ~ REF CreatorRep;
CreatorRep:
TYPE ~
RECORD [
type: ATOM, -- $KS, $SD, etc.; matches version.representation
MetricVersion: PROC [self: Creator, name: ROPE] RETURNS [Version],
MaskVersion: PROC [self: Creator, name: ROPE] RETURNS [Version],
NewTypeface: PROC [self: Creator, name: ROPE, version: Version] RETURNS [Typeface],
NewMasks: PROC [self: Creator, name: ROPE, version: Version, typeface: Typeface] RETURNS [Masks],
priority: INTEGER ← 0,
data: REF
];
RegisterCreator:
PROC [creator: Creator];
The MetricVersion and MaskVersion procs of the registered creators are called in priority order, each getting a chance to claim the typeface by returning a non-null Version. In case of a priority clash, the last one registered is tried first. Only one creator of a given type is registered at any given time.
LookupVersions:
PROC [name:
ROPE]
RETURNS [metricVersion, maskVersion: Version];
Finds the version stamps for the metrics and masks with the given name.
NewMetrics:
PROC [name:
ROPE, version: Version]
RETURNS [Metrics];
NewMasks:
PROC [name:
ROPE, version: Version, metrics: Metrics]
RETURNS [Masks];
END.