mediawiki-extensions-Math/modules/MathJax/jax/output/HTML-CSS/autoload/multiline.js
2012-03-01 01:21:20 +00:00

540 lines
21 KiB
JavaScript

/*************************************************************
*
* MathJax/jax/output/HTML-CSS/autoload/multiline.js
*
* Implements the HTML-CSS output for <mrow>'s that contain line breaks.
*
* ---------------------------------------------------------------------
*
* Copyright (c) 2010-2012 Design Science, Inc.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
MathJax.Hub.Register.StartupHook("HTML-CSS Jax Ready",function () {
var VERSION = "2.0";
var MML = MathJax.ElementJax.mml,
HTMLCSS = MathJax.OutputJax["HTML-CSS"];
//
// Penalties for the various line breaks
//
var PENALTY = {
newline: 0,
nobreak: 1000000,
goodbreak: [-200],
badbreak: [+200],
auto: [0],
toobig: 500,
nestfactor: 400,
spacefactor: -100,
spaceoffset: 2,
spacelimit: 1, // spaces larger than this get a penalty boost
fence: 500,
close: 500
};
var ENDVALUES = {linebreakstyle: "after"};
/**************************************************************************/
MML.mbase.Augment({
HTMLlinebreakPenalty: PENALTY,
/****************************************************************/
//
// Handle breaking an mrow into separate lines
//
HTMLmultiline: function (span) {
//
// Find the parent element and mark it as multiline
//
var parent = this;
while (parent.inferred || (parent.parent && parent.parent.type === "mrow" &&
parent.parent.data.length === 1)) {parent = parent.parent}
var isTop = ((parent.type === "math" && parent.Get("display") === "block") ||
parent.type === "mtd");
parent.isMultiline = true;
//
// Default values for the line-breaking parameters
//
var VALUES = this.getValues(
"linebreak","linebreakstyle","lineleading","linebreakmultchar",
"indentalign","indentshift",
"indentalignfirst","indentshiftfirst",
"indentalignlast","indentshiftlast"
);
if (VALUES.linebreakstyle === MML.LINEBREAKSTYLE.INFIXLINEBREAKSTYLE)
{VALUES.linebreakstyle = this.Get("infixlinebreakstyle")}
VALUES.lineleading = HTMLCSS.length2em(VALUES.lineleading,1,0.5);
//
// Remove old color and break the span at its best line breaks
//
this.HTMLremoveColor(span);
var stack = HTMLCSS.createStack(span);
var state = {
n: 0, Y: 0,
scale: this.HTMLgetScale(),
isTop: isTop,
values: {},
VALUES: VALUES
},
align = this.HTMLgetAlign(state,{}),
shift = this.HTMLgetShift(state,{},align),
start = [],
end = {
index:[], penalty:PENALTY.nobreak,
w:0, W:shift, shift:shift, scanW:shift,
nest: 0
},
broken = false;
while (this.HTMLbetterBreak(end,state) &&
(end.scanW >= HTMLCSS.linebreakWidth || end.penalty == PENALTY.newline)) {
this.HTMLaddLine(stack,start,end.index,state,end.values,broken);
start = end.index.slice(0); broken = true;
align = this.HTMLgetAlign(state,end.values);
shift = this.HTMLgetShift(state,end.values,align);
if (align === MML.INDENTALIGN.CENTER) {shift = 0}
end.W = end.shift = end.scanW = shift; end.penalty = PENALTY.nobreak;
}
state.isLast = true;
this.HTMLaddLine(stack,start,[],state,ENDVALUES,broken);
//
// Make top-level spans 100% wide.
// Finish up the space and add the color again
//
if (isTop) {
stack.style.width = "100%";
if (parent.type === "math") {span.bbox.width = "100%"}
}
this.HTMLhandleSpace(span);
this.HTMLhandleColor(span);
span.bbox.isMultiline = true;
return span;
},
/****************************************************************/
//
// Locate the next linebreak that is better than the current one
//
HTMLbetterBreak: function (info,state) {
if (this.isToken) {return false} // FIXME: handle breaking of token elements
if (this.isEmbellished()) {
info.embellished = this;
return this.CoreMO().HTMLbetterBreak(info,state);
}
if (this.linebreakContainer) {return false}
//
// Get the current breakpoint position and other data
//
var index = info.index.slice(0), i = info.index.shift(),
m = this.data.length, W, scanW = info.W,
broken = (info.index.length > 0), better = false;
if (i == null) {i = -1}; if (!broken) {i++; info.W += info.w};
info.w = 0; info.nest++;
//
// Look through the line for breakpoints,
// (as long as we are not too far past the breaking width)
//
while (i < m && info.W < 1.33*HTMLCSS.linebreakWidth) {
if (this.data[i]) {
if (this.data[i].HTMLbetterBreak(info,state)) {
better = true; index = [i].concat(info.index); W = info.W;
if (info.penalty === PENALTY.newline) {info.index = index; info.nest--; return true}
}
if (!broken) {
var span = this.data[i].HTMLspanElement();
scanW += span.bbox.w;
if (span.style.paddingLeft) {scanW += parseFloat(span.style.paddingLeft)}
if (span.style.paddingRight) {scanW += parseFloat(span.style.paddingRight)}
info.W = info.scanW = scanW;
}
}
info.index = []; i++; broken = false;
}
info.nest--; info.index = index;
if (better) {info.W = W}
return better;
},
/****************************************************************/
//
// Create a new line and move the required elements into it
// Position it using proper alignment and indenting
//
HTMLaddLine: function (stack,start,end,state,values,broken) {
//
// Create a box for the line, with empty BBox
// fill it with the proper elements,
// and clean up the bbox
//
line = HTMLCSS.createBox(stack);
line.bbox = this.HTMLemptyBBox({});
state.first = broken; state.last = true;
this.HTMLmoveLine(start,end,line,state,values);
this.HTMLcleanBBox(line.bbox);
//
// Get the alignment and shift values
//
var align = this.HTMLgetAlign(state,values),
shift = this.HTMLgetShift(state,values,align);
//
// Add in space for the shift
//
if (shift) {
HTMLCSS.createBlank(line,shift,(align !== MML.INDENTALIGN.RIGHT));
line.bbox.w += shift; line.bbox.rw += shift;
}
//
// Set the Y offset based on previous depth, leading, and current height
//
if (state.n > 0) {
var LHD = HTMLCSS.FONTDATA.baselineskip * state.scale;
var leading = (state.values.lineleading == null ? state.VALUES : state.values).lineleading;
state.Y -= Math.max(LHD,state.d + line.bbox.h + leading);
}
//
// Place the new line
//
HTMLCSS.alignBox(line,align,state.Y);
//
// Save the values needed for the future
//
state.d = line.bbox.d; state.values = values; state.n++;
},
/****************************************************************/
//
// Get alignment and shift values from the given data
//
HTMLgetAlign: function (state,values) {
var cur = values, prev = state.values, def = state.VALUES, align;
if (state.n === 0) {align = cur.indentalignfirst || prev.indentalignfirst || def.indentalignfirst}
else if (state.isLast) {align = prev.indentalignlast || def.indentalignlast}
else {align = prev.indentalign || def.indentalign}
if (align === MML.INDENTALIGN.INDENTALIGN) {align = prev.indentalign || def.indentalign}
if (align === MML.INDENTALIGN.AUTO) {align = (state.isTop ? this.displayAlign : MML.INDENTALIGN.LEFT)}
return align;
},
HTMLgetShift: function (state,values,align) {
if (align === MML.INDENTALIGN.CENTER) {return 0}
var cur = values, prev = state.values, def = state.VALUES, shift;
if (state.n === 0) {shift = cur.indentshiftfirst || prev.indentshiftfirst || def.indentshiftfirst}
else if (state.isLast) {shift = prev.indentshiftlast || def.indentshiftlast}
else {shift = prev.indentshift || def.indentshift}
if (shift === MML.INDENTSHIFT.INDENTSHIFT) {shift = prev.indentshift || def.indentshift}
if (shift === "auto" || shift === "") {shift = (state.isTSop ? this.displayIndent : "0")}
return HTMLCSS.length2em(shift,0);
},
/****************************************************************/
//
// Move the selected elements into the new line's span,
// moving whole items when possible, and parts of ones
// that are split by a line break.
//
HTMLmoveLine: function (start,end,span,state,values) {
var i = start[0], j = end[0];
if (i == null) {i = -1}; if (j == null) {j = this.data.length-1}
if (i === j && start.length > 1) {
//
// If starting and ending in the same element move the subpiece to the new line
//
this.data[i].HTMLmoveSlice(start.slice(1),end.slice(1),span,state,values,"paddingLeft");
} else {
//
// Otherwise, move the remainder of the initial item
// and any others up tp the last one
//
var last = state.last; state.last = false;
while (i < j) {
if (this.data[i]) {
if (start.length <= 1) {this.data[i].HTMLmoveSpan(span,state,values)}
else {this.data[i].HTMLmoveSlice(start.slice(1),[],span,state,values,"paddingLeft")}
}
i++; state.first = false; start = [];
}
//
// If the last item is complete, move it,
// otherwise move the first part of it up to the split
//
state.last = last;
if (this.data[i]) {
if (end.length <= 1) {this.data[i].HTMLmoveSpan(span,state,values)}
else {this.data[i].HTMLmoveSlice([],end.slice(1),span,state,values,"paddingRight")}
}
}
},
/****************************************************************/
//
// Split an element and copy the selected items into the new part
//
HTMLmoveSlice: function (start,end,span,state,values,padding) {
//
// Get rid of color, if any (added back in later)
// Create a new span for the slice of the element
// Move the selected portion into the slice
// If it is the last slice
// Remove the original (now empty) span
// Rename the Continue-0 span with the original name (for HTMLspanElement)
// Add back the color
//
this.HTMLremoveColor();
var slice = this.HTMLcreateSliceSpan(span);
this.HTMLmoveLine(start,end,slice,state,values);
slice.style[padding] = "";
this.HTMLcombineBBoxes(slice,span.bbox);
this.HTMLcleanBBox(slice.bbox);
if (end.length === 0) {
span = this.HTMLspanElement();
span.parentNode.removeChild(span);
span.nextMathJaxSpan.id = span.id; var n = 0;
while (span = span.nextMathJaxSpan) {
var color = this.HTMLhandleColor(span);
if (color) {color.id += "-MathJax-Continue-"+n; n++}
}
}
return slice;
},
/****************************************************************/
//
// Create a new span for an element that is split in two
// Clone the original and update its ID.
// Link the old span to the new one so we can find it later
//
HTMLcreateSliceSpan: function (span) {
var SPAN = this.HTMLspanElement(), n = 0;
var LAST = SPAN; while (LAST.nextMathJaxSpan) {LAST = LAST.nextMathJaxSpan; n++}
var SLICE = SPAN.cloneNode(false); LAST.nextMathJaxSpan = SLICE; SLICE.nextMathJaxSpan = null;
SLICE.id += "-MathJax-Continue-"+n;
SLICE.bbox = this.HTMLemptyBBox({});
return span.appendChild(SLICE);
},
/****************************************************************/
//
// Move an element from its original span to its new location in
// a split element or the new line's span
//
HTMLmoveSpan: function (line,state,values) {
// FIXME: handle linebreakstyle === "duplicate"
// FIXME: handle linebreakmultchar
if (!(state.first || state.last) ||
(state.first && state.values.linebreakstyle === MML.LINEBREAKSTYLE.BEFORE) ||
(state.last && values.linebreakstyle === MML.LINEBREAKSTYLE.AFTER)) {
//
// Move color and span
//
var color = document.getElementById("MathJax-Color-"+this.spanID+HTMLCSS.idPostfix);
if (color) {line.appendChild(color)}
var span = this.HTMLspanElement();
line.appendChild(span);
//
// If it is last, remove right padding
// If it is first, remove left padding and recolor
//
if (state.last) {span.style.paddingRight = ""}
if (state.first || state.nextIsFirst) {
delete state.nextIsFirst;
span.style.paddingLeft = "";
if (color) {this.HTMLremoveColor(span); this.HTMLhandleColor(span)}
}
//
// Update bounding box
//
this.HTMLcombineBBoxes(this,line.bbox);
} else if (state.first) {state.nextIsFirst = true} else {delete state.nextIsFirst}
}
});
/**************************************************************************/
MML.mo.Augment({
//
// Override the method for checking line breaks to properly handle <mo>
//
HTMLbetterBreak: function (info,state) {
var values = this.getValues(
"linebreak","linebreakstyle","lineleading","linebreakmultchar",
"indentalign","indentshift",
"indentalignfirst","indentshiftfirst",
"indentalignlast","indentshiftlast",
"texClass", "fence"
);
if (values.linebreakstyle === MML.LINEBREAKSTYLE.INFIXLINEBREAKSTYLE)
{values.linebreakstyle = this.Get("infixlinebreakstyle")}
//
// Adjust nesting by TeX class (helps output that does not include
// mrows for nesting, but can leave these unbalanced.
//
if (values.texClass === MML.TEXCLASS.OPEN) {info.nest++}
if (values.texClass === MML.TEXCLASS.CLOSE) {info.nest--}
//
// Get the default penalty for this location
//
var W = info.W, mo = (info.embellished||this); delete info.embellished;
var span = mo.HTMLspanElement(), w = span.bbox.w;
if (span.style.paddingLeft) {w += parseFloat(span.style.paddingLeft)}
if (values.linebreakstyle === MML.LINEBREAKSTYLE.AFTER) {W += w; w = 0}
if (W - info.shift === 0) {return false} // don't break at zero width (FIXME?)
var offset = HTMLCSS.linebreakWidth - W;
// Adjust offest for explicit first-line indent and align
if (state.n === 0 && (values.indentshiftfirst !== state.VALUES.indentshiftfirst ||
values.indentalignfirst !== state.VALUES.indentalignfirst)) {
var align = this.HTMLgetAlign(state,values),
shift = this.HTMLgetShift(state,values,align);
offset += (info.shift - shift);
}
//
var penalty = Math.floor(offset / HTMLCSS.linebreakWidth * 1000);
if (penalty < 0) {penalty = PENALTY.toobig - 3*penalty}
if (values.fence) {penalty += PENALTY.fence}
if ((values.linebreakstyle === MML.LINEBREAKSTYLE.AFTER &&
values.texClass === MML.TEXCLASS.OPEN) ||
values.texClass === MML.TEXCLASS.CLOSE) {penalty += PENALTY.close}
penalty += info.nest * PENALTY.nestfactor;
//
// Get the penalty for this type of break and
// use it to modify the default penalty
//
var linebreak = PENALTY[values.linebreak||MML.LINEBREAK.AUTO];
if (!(linebreak instanceof Array)) {
// for breaks past the width, don't modify penalty
if (offset >= 0) {penalty = linebreak * info.nest}
} else {penalty = Math.max(1,penalty + linebreak[0] * info.nest)}
//
// If the penalty is no better than the current one, return false
// Otherwise save the data for this breakpoint and return true
//
if (penalty >= info.penalty) {return false}
info.penalty = penalty; info.values = values; info.W = W; info.w = w;
values.lineleading = HTMLCSS.length2em(values.lineleading,state.VALUES.lineleading);
return true;
}
});
/**************************************************************************/
MML.mspace.Augment({
//
// Override the method for checking line breaks to properly handle <mspace>
//
HTMLbetterBreak: function (info,state) {
var values = this.getValues("linebreak");
//
// Get the default penalty for this location
//
var W = info.W, span = this.HTMLspanElement(), w = span.bbox.w;
if (span.style.paddingLeft) {w += parseFloat(span.style.paddingLeft)}
if (values.linebreakstyle === MML.LINEBREAKSTYLE.AFTER) {W += w; w = 0}
if (W - info.shift === 0) {return false} // don't break at zero width (FIXME?)
var offset = HTMLCSS.linebreakWidth - W;
//
var penalty = Math.floor(offset / HTMLCSS.linebreakWidth * 1000);
if (penalty < 0) {penalty = PENALTY.toobig - 3*penalty}
penalty += info.nest * PENALTY.nestfactor;
//
// Get the penalty for this type of break and
// use it to modify the default penalty
//
var linebreak = PENALTY[values.linebreak||MML.LINEBREAK.AUTO];
if (values.linebreak === MML.LINEBREAK.AUTO && w >= PENALTY.spacelimit)
{linebreak = [(w+PENALTY.spaceoffset)*PENALTY.spacefactor]}
if (!(linebreak instanceof Array)) {
// for breaks past the width, don't modify penalty
if (offset >= 0) {penalty = linebreak * info.nest}
} else {penalty = Math.max(1,penalty + linebreak[0] * info.nest)}
//
// If the penalty is no better than the current one, return false
// Otherwise save the data for this breakpoint and return true
//
if (penalty >= info.penalty) {return false}
info.penalty = penalty; info.values = values; info.W = W; info.w = w;
values.lineleading = state.VALUES.lineleading; values.linebreakstyle = "before";
return true;
}
});
//
// Hook into the mathchoice extension
//
MathJax.Hub.Register.StartupHook("TeX mathchoice Ready",function () {
MML.TeXmathchoice.Augment({
HTMLbetterBreak: function (info,state) {
return this.Core().HTMLbetterBreak(info,state);
},
HTMLmoveLine: function (start,end,span,state,values) {
return this.Core().HTMLmoveSlice(start,end,span,state,values);
}
});
});
//
// Have maction process only the selected item
//
MML.maction.Augment({
HTMLbetterBreak: function (info,state) {
return this.Core().HTMLbetterBreak(info,state);
},
HTMLmoveLine: function (start,end,span,state,values) {
return this.Core().HTMLmoveSlice(start,end,span,state,values);
},
//
// Split and move the hit boxes as well
//
HTMLmoveSlice: function (start,end,span,state,values,padding) {
var hitbox = document.getElementById("MathJax-HitBox-"+this.spanID+HTMLCSS.idPostfix);
if (hitbox) {hitbox.parentNode.removeChild(hitbox)}
var slice = this.SUPER(arguments).HTMLmoveSlice.apply(this,arguments);
if (end.length === 0) {
span = this.HTMLspanElement(); var n = 0;
while (span) {
hitbox = this.HTMLhandleHitBox(span,"-Continue-"+n);
span = span.nextMathJaxSpan; n++;
}
}
return slice;
}
});
//
// Have semantics only do the first element
// (FIXME: do we need to do anything special about annotation-xml?)
//
MML.semantics.Augment({
HTMLbetterBreak: function (info,state) {
return (this.data[0] ? this.data[0].HTMLbetterBreak(info,state) : false);
},
HTMLmoveLine: function (start,end,span,state,values) {
return (this.data[0] ? this.data[0].HTMLmoveSlice(start,end,span,state,values) : null);
}
});
/**************************************************************************/
MathJax.Hub.Startup.signal.Post("HTML-CSS multiline Ready");
MathJax.Ajax.loadComplete(HTMLCSS.autoloadDir+"/multiline.js");
});