[Indigo]<CaminoReal>MathToTioga.mesa!2

MathToTioga.mesa

Carl Waldspurger, September 1, 1986 3:52:09 pm PDT

Rick Beach, September 2, 1987 9:53:44 am PDT

DIRECTORY

TEditFormat,

TextNode USING [Location],

NodeStyle USING [Ref],

NodeStyleOps USING [OfStyle],

NodeProps USING [PutProp],

Rope USING [ROPE, Cat, Find],

Convert USING [RopeFromReal, RealFromRope, Error],

Commander USING [Register, CommandProc],

TextEdit USING [GetCharProp],

Imager USING [DoSaveAll, Move, Context],

MathBox,

MathExpr USING [ExprFromRope, EXPR, parseError],

MathConstructors,

MathDisplayExpr USING [DisplayExpr, DisplayExprFromExpr, Format, Paint],

Evaluator,

AlgebraClasses,

ViewExpr;

MathToTioga: CEDAR PROGRAM

IMPORTS TEditFormat, TextEdit, Imager, Rope, MathBox, MathConstructors, MathExpr,
MathDisplayExpr, NodeProps, Convert, Commander, AlgebraClasses, Evaluator, ViewExpr ~

BEGIN

Abbreviations For Imported Types

ROPE: TYPE ~ Rope.ROPE;

BOX: TYPE ~ MathBox.BOX;

EXPR: TYPE ~ MathExpr.EXPR;

DisplayExpr: TYPE ~ MathDisplayExpr.DisplayExpr;

CharacterArtworkClass: TYPE ~ TEditFormat.CharacterArtworkClass;

CharacterArtworkClassRep: TYPE ~ TEditFormat.CharacterArtworkClassRep;

CharacterArtwork: TYPE ~ TEditFormat.CharacterArtwork;

CharacterArtworkRep: TYPE ~ TEditFormat.CharacterArtworkRep;

Private Type Defs (local to module)

PaintInfo: TYPE ~ REF PaintInfoRep;

PaintInfoRep: TYPE ~ RECORD [

expr: DisplayExpr ← NIL,

box: BOX ← NIL

];

Control evaluation

EvalFirst: BOOL ← FALSE;

Procedures

RegisterMathExprArtworkClass: PROC[] ~ {

effects: Registers $MeddleExpr as a Tioga character artwork class.

create the class

class: CharacterArtworkClass ← NEW[CharacterArtworkClassRep ←

[name: $MeddleExpr, format: FormatMathExpr, data: NIL]];

register it

TEditFormat.RegisterCharacterArtwork[class];

};

UnRegisterMathExprArtworkClass: PROC[] ~ {

effects: Unregisters $MeddleExpr as a Tioga character artwork class.

TEditFormat.UnregisterCharacterArtwork[$MeddleExpr];

};

FormatMathExpr: PROC[class: CharacterArtworkClass, loc: TextNode.Location, style: NodeStyle.Ref, styleOps: NodeStyleOps.OfStyle] RETURNS[CharacterArtwork] ~ {

effects: Formats math expression artwork represented by ROPE at loc.

Returns character artwork for formatted expression.

local declarations

TeXToTioga: REAL ~ 20.0; -- default scaling factor from unit-sized TeX Fonts to Tioga

mathExpr: EXPR ← NIL;

object: AlgebraClasses.Object;

displayExpr: DisplayExpr ← NIL;

displayBox: BOX ← NIL;

charArtwork: CharacterArtwork;

postfixValue, leading, topLeading, bottomLeading: ROPE ← NIL; -- for postfix properties

pointSize: REAL ← TeXToTioga; -- point size to use when rendering MEDDLE expr

linearExpr: ROPE ← NARROW[TextEdit.GetCharProp[node: loc.node, index: loc.where, name: $MeddleExpr]];

if the user specified a point size to use, get it and use it

exprPointSize: ROPE ← NARROW[TextEdit.GetCharProp[node: loc.node, index: loc.where, name: $MeddlePtSize]];

IF exprPointSize # NIL THEN pointSize ← Convert.RealFromRope[exprPointSize ! Convert.Error => CONTINUE];

convert linear form of expression to internal form

mathExpr ← MathExpr.ExprFromRope[ViewExpr.StripHeader[linearExpr] ! MathExpr.parseError => {mathExpr ← MathConstructors.MakePlaceHolder[]; CONTINUE}];

check for evaluation flag

IF EvalFirst THEN {

object ← Evaluator.Eval[mathExpr];

mathExpr ← AlgebraClasses.ApplyLkpNoRecastExpr[$toExpr, object.class, LIST[object] ];

};

convert immutable expression to mutable display form

displayExpr ← MathDisplayExpr.DisplayExprFromExpr[mathExpr];

format expression and get box dimensions

displayBox ← displayExpr.Format[normal];

scale box dimensions from TeX unit sizes to some reasonable size

displayBox ← MathBox.Scale[displayBox, [pointSize, pointSize]];

compute appropriate postfix point values to place on current node

in order to set a maximum value, the following JaM code fragment does this

mumble pt the leading 2 .copy .gt 3 1 .roll .ifelse leading

leading ← Convert.RopeFromReal[displayBox.Height[]];

topLeading ← Convert.RopeFromReal[displayBox.Extents[].ascent + 12.0];

bottomLeading ← Convert.RopeFromReal[displayBox.Extents[].descent + 12.0];

postfixValue ← Rope.Cat[leading, " pt the leading 2 .copy .gt 3 1 .roll .ifelse leading "];

postfixValue ← Rope.Cat[postfixValue, topLeading, " pt the topLeading 2 .copy .gt 3 1 .roll .ifelse topLeading "];

postfixValue ← Rope.Cat[postfixValue, topLeading, " pt the topIndent 2 .copy .gt 3 1 .roll .ifelse topIndent "];

postfixValue ← Rope.Cat[postfixValue, bottomLeading, " pt the bottomLeading 2 .copy .gt 3 1 .roll .ifelse bottomLeading "];

put Postfix properties on node containing displayExpr to insure proper spacing

NodeProps.PutProp[loc.node, $Postfix, postfixValue];

create artwork char

charArtwork ← NEW[CharacterArtworkRep ←

[paint: PaintMathExpr, extents: displayBox.Extents[], escapement: [displayBox.Width[], 0.0], data: NEW[PaintInfoRep ← [expr: displayExpr, box: displayBox]]]];

RETURN[charArtwork];

};

PaintMathExpr: PROC[charArtwork: CharacterArtwork, context: Imager.Context] ~ {

effects: Paints charArtwork onto context.

retrieve painting information

paintInfo: PaintInfo ← NARROW[charArtwork.data];

set offset to zero (context origin)

absBox: BOX ← MathBox.ChangeOffset[paintInfo.box, [0.0, 0.0]];

local procedure to do painting within a DoSaveAll

DoPaint: PROC[] ~ {

Imager.Move[context];

MathDisplayExpr.Paint[paintInfo.expr, context, absBox, NIL];

};

pretend that current x,y position in context is origin while actually painting

Imager.DoSaveAll[context, DoPaint];

};

DoIt: Commander.CommandProc ~ {

effects: If command line contains "off" then unregisters $MeddleExpr Artwork.

Otherwise registers $MeddleExpr Artwork.

IF Rope.Find[s1: cmd.commandLine, s2: "off", case: FALSE] # -1 THEN {

UnRegisterMathExprArtworkClass[];

[] ← TEditFormat.SetArtworkEnabled[FALSE];

}

ELSE {

RegisterMathExprArtworkClass[];

[] ← TEditFormat.SetArtworkEnabled[TRUE];

};

SetEval: Commander.CommandProc ~ {

effects: Turn on evaluation before painting Tioga doc

IF Rope.Find[s1: cmd.commandLine, s2: "on", case: FALSE] # -1 THEN

EvalFirst ← TRUE

ELSE

EvalFirst ← FALSE;

};

Start Code

register command to turn $MeddleExpr artwork on and off

Commander.Register[key: "MeddleArtwork", proc: DoIt, doc: "Turns MEDDLE Artwork Interpretation On/Off for Tioga"];

register command to turn evaluation before painting on and off

Commander.Register[key: "MathEval", proc: SetEval, doc: "Turns CaminoReal Math Evaluation On/Off for Tioga"];

END.