pdf.js/src/canvas.js

1236 lines
39 KiB
JavaScript

/* -*- Mode: Java; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* vim: set shiftwidth=2 tabstop=2 autoindent cindent expandtab: */
'use strict';
// <canvas> contexts store most of the state we need natively.
// However, PDF needs a bit more state, which we store here.
var TextRenderingMode = {
FILL: 0,
STROKE: 1,
FILL_STROKE: 2,
INVISIBLE: 3,
FILL_ADD_TO_PATH: 4,
STROKE_ADD_TO_PATH: 5,
FILL_STROKE_ADD_TO_PATH: 6,
ADD_TO_PATH: 7
};
var CanvasExtraState = (function CanvasExtraStateClosure() {
function CanvasExtraState(old) {
// Are soft masks and alpha values shapes or opacities?
this.alphaIsShape = false;
this.fontSize = 0;
this.textMatrix = IDENTITY_MATRIX;
this.leading = 0;
// Current point (in user coordinates)
this.x = 0;
this.y = 0;
// Start of text line (in text coordinates)
this.lineX = 0;
this.lineY = 0;
// Character and word spacing
this.charSpacing = 0;
this.wordSpacing = 0;
this.textHScale = 1;
this.textRenderingMode = TextRenderingMode.FILL;
// Color spaces
this.fillColorSpace = new DeviceGrayCS();
this.fillColorSpaceObj = null;
this.strokeColorSpace = new DeviceGrayCS();
this.strokeColorSpaceObj = null;
this.fillColorObj = null;
this.strokeColorObj = null;
// Default fore and background colors
this.fillColor = '#000000';
this.strokeColor = '#000000';
// Note: fill alpha applies to all non-stroking operations
this.fillAlpha = 1;
this.strokeAlpha = 1;
this.old = old;
}
CanvasExtraState.prototype = {
clone: function canvasextra_clone() {
return Object.create(this);
},
setCurrentPoint: function canvasextra_setCurrentPoint(x, y) {
this.x = x;
this.y = y;
}
};
return CanvasExtraState;
})();
function ScratchCanvas(width, height) {
var canvas = document.createElement('canvas');
canvas.width = width;
canvas.height = height;
return canvas;
}
function addContextCurrentTransform(ctx) {
// If the context doesn't expose a `mozCurrentTransform`, add a JS based on.
if (!ctx.mozCurrentTransform) {
// Store the original context
ctx._originalSave = ctx.save;
ctx._originalRestore = ctx.restore;
ctx._originalRotate = ctx.rotate;
ctx._originalScale = ctx.scale;
ctx._originalTranslate = ctx.translate;
ctx._originalTransform = ctx.transform;
ctx._transformMatrix = [1, 0, 0, 1, 0, 0];
ctx._transformStack = [];
Object.defineProperty(ctx, 'mozCurrentTransform', {
get: function getCurrentTransform() {
return this._transformMatrix;
}
});
Object.defineProperty(ctx, 'mozCurrentTransformInverse', {
get: function getCurrentTransformInverse() {
// Calculation done using WolframAlpha:
// http://www.wolframalpha.com/input/?
// i=Inverse+{{a%2C+c%2C+e}%2C+{b%2C+d%2C+f}%2C+{0%2C+0%2C+1}}
var m = this._transformMatrix;
var a = m[0], b = m[1], c = m[2], d = m[3], e = m[4], f = m[5];
var ad_bc = a * d - b * c;
var bc_ad = b * c - a * d;
return [
d / ad_bc,
b / bc_ad,
c / bc_ad,
a / ad_bc,
(d * e - c * f) / bc_ad,
(b * e - a * f) / ad_bc
];
}
});
ctx.save = function ctxSave() {
var old = this._transformMatrix;
this._transformStack.push(old);
this._transformMatrix = old.slice(0, 6);
this._originalSave();
};
ctx.restore = function ctxRestore() {
var prev = this._transformStack.pop();
if (prev) {
this._transformMatrix = prev;
this._originalRestore();
}
};
ctx.translate = function ctxTranslate(x, y) {
var m = this._transformMatrix;
m[4] = m[0] * x + m[2] * y + m[4];
m[5] = m[1] * x + m[3] * y + m[5];
this._originalTranslate(x, y);
};
ctx.scale = function ctxScale(x, y) {
var m = this._transformMatrix;
m[0] = m[0] * x;
m[1] = m[1] * x;
m[2] = m[2] * y;
m[3] = m[3] * y;
this._originalScale(x, y);
};
ctx.transform = function ctxTransform(a, b, c, d, e, f) {
var m = this._transformMatrix;
this._transformMatrix = [
m[0] * a + m[2] * b,
m[1] * a + m[3] * b,
m[0] * c + m[2] * d,
m[1] * c + m[3] * d,
m[0] * e + m[2] * f + m[4],
m[1] * e + m[3] * f + m[5]
];
ctx._originalTransform(a, b, c, d, e, f);
};
ctx.rotate = function ctxRotate(angle) {
var cosValue = Math.cos(angle);
var sinValue = Math.sin(angle);
var m = this._transformMatrix;
this._transformMatrix = [
m[0] * cosValue + m[2] * sinValue,
m[1] * cosValue + m[3] * sinValue,
m[0] * (-sinValue) + m[2] * cosValue,
m[1] * (-sinValue) + m[3] * cosValue,
m[4],
m[5]
];
this._originalRotate(angle);
};
}
}
var CanvasGraphics = (function CanvasGraphicsClosure() {
// Defines the time the executeIRQueue is going to be executing
// before it stops and shedules a continue of execution.
var kExecutionTime = 50;
function CanvasGraphics(canvasCtx, objs, textLayer) {
this.ctx = canvasCtx;
this.current = new CanvasExtraState();
this.stateStack = [];
this.pendingClip = null;
this.res = null;
this.xobjs = null;
this.ScratchCanvas = ScratchCanvas;
this.objs = objs;
this.textLayer = textLayer;
if (canvasCtx) {
addContextCurrentTransform(canvasCtx);
}
}
var LINE_CAP_STYLES = ['butt', 'round', 'square'];
var LINE_JOIN_STYLES = ['miter', 'round', 'bevel'];
var NORMAL_CLIP = {};
var EO_CLIP = {};
CanvasGraphics.prototype = {
slowCommands: {
'stroke': true,
'closeStroke': true,
'fill': true,
'eoFill': true,
'fillStroke': true,
'eoFillStroke': true,
'closeFillStroke': true,
'closeEOFillStroke': true,
'showText': true,
'showSpacedText': true,
'setStrokeColorSpace': true,
'setFillColorSpace': true,
'setStrokeColor': true,
'setStrokeColorN': true,
'setFillColor': true,
'setFillColorN_IR': true,
'setStrokeGray': true,
'setFillGray': true,
'setStrokeRGBColor': true,
'setFillRGBColor': true,
'setStrokeCMYKColor': true,
'setFillCMYKColor': true,
'paintJpegXObject': true,
'paintImageXObject': true,
'paintImageMaskXObject': true,
'shadingFill': true
},
beginDrawing: function canvasGraphicsBeginDrawing(mediaBox) {
var cw = this.ctx.canvas.width, ch = this.ctx.canvas.height;
this.ctx.save();
switch (mediaBox.rotate) {
case 0:
this.ctx.transform(1, 0, 0, -1, 0, ch);
break;
case 90:
this.ctx.transform(0, 1, 1, 0, 0, 0);
break;
case 180:
this.ctx.transform(-1, 0, 0, 1, cw, 0);
break;
case 270:
this.ctx.transform(0, -1, -1, 0, cw, ch);
break;
}
// Scale so that canvas units are the same as PDF user space units
this.ctx.scale(cw / mediaBox.width, ch / mediaBox.height);
this.textDivs = [];
this.textLayerQueue = [];
// Prevent textLayerQueue from being rendered while rendering a new page
if (this.textLayerTimer)
clearInterval(this.textLayerTimer);
},
executeIRQueue: function canvasGraphicsExecuteIRQueue(codeIR,
executionStartIdx, continueCallback) {
var argsArray = codeIR.argsArray;
var fnArray = codeIR.fnArray;
var i = executionStartIdx || 0;
var argsArrayLen = argsArray.length;
// Sometimes the IRQueue to execute is empty.
if (argsArrayLen == i) {
return i;
}
var executionEndIdx;
var endTime = Date.now() + kExecutionTime;
var objs = this.objs;
var fnName;
var slowCommands = this.slowCommands;
while (true) {
fnName = fnArray[i];
if (fnName !== 'dependency') {
this[fnName].apply(this, argsArray[i]);
} else {
var deps = argsArray[i];
for (var n = 0, nn = deps.length; n < nn; n++) {
var depObjId = deps[n];
// If the promise isn't resolved yet, add the continueCallback
// to the promise and bail out.
if (!objs.isResolved(depObjId)) {
objs.get(depObjId, continueCallback);
return i;
}
}
}
i++;
// If the entire IRQueue was executed, stop as were done.
if (i == argsArrayLen) {
return i;
}
// If the execution took longer then a certain amount of time, shedule
// to continue exeution after a short delay.
// However, this is only possible if a 'continueCallback' is passed in.
if (continueCallback && slowCommands[fnName] && Date.now() > endTime) {
setTimeout(continueCallback, 0);
return i;
}
// If the IRQueue isn't executed completly yet OR the execution time
// was short enough, do another execution round.
}
},
endDrawing: function canvasGraphicsEndDrawing() {
this.ctx.restore();
var textLayer = this.textLayer;
if (!textLayer)
return;
var self = this;
var textDivIndex = 0;
var renderTextLayer = function canvasRenderTextLayer() {
var finished = false;
var textDivs = self.textDivs;
if (textDivIndex < textDivs.length) {
var textDiv = textDivs[textDivIndex++];
if (textDiv.dataset.textLength > 1) { // avoid div by zero
textLayer.appendChild(textDiv);
// Adjust div width (via letterSpacing) to match canvas text
// Due to the .offsetWidth calls, this is slow
textDiv.style.letterSpacing =
((textDiv.dataset.canvasWidth - textDiv.offsetWidth) /
(textDiv.dataset.textLength - 1)) + 'px';
}
}
else
finished = true;
return finished;
}
var textLayerQueue = this.textLayerQueue;
textLayerQueue.push(renderTextLayer);
// Lazy textLayer rendering (to prevent UI hangs)
// Only render queue if activity has stopped, where "no activity" ==
// "no beginDrawing() calls in the last N ms"
this.textLayerTimer = setInterval(function renderTextLayerQueue() {
// Render most recent (==most relevant) layers first
for (var i = textLayerQueue.length - 1; i >= 0; i--) {
var finished = textLayerQueue[i].call();
if (finished)
textLayerQueue.splice(i, 1);
}
if (textLayerQueue.length == 0)
clearInterval(this.textLayerTimer);
}, 1);
},
// Graphics state
setLineWidth: function canvasGraphicsSetLineWidth(width) {
this.ctx.lineWidth = width;
},
setLineCap: function canvasGraphicsSetLineCap(style) {
this.ctx.lineCap = LINE_CAP_STYLES[style];
},
setLineJoin: function canvasGraphicsSetLineJoin(style) {
this.ctx.lineJoin = LINE_JOIN_STYLES[style];
},
setMiterLimit: function canvasGraphicsSetMiterLimit(limit) {
this.ctx.miterLimit = limit;
},
setDash: function canvasGraphicsSetDash(dashArray, dashPhase) {
this.ctx.mozDash = dashArray;
this.ctx.mozDashOffset = dashPhase;
},
setRenderingIntent: function canvasGraphicsSetRenderingIntent(intent) {
TODO('set rendering intent: ' + intent);
},
setFlatness: function canvasGraphicsSetFlatness(flatness) {
TODO('set flatness: ' + flatness);
},
setGState: function canvasGraphicsSetGState(states) {
for (var i = 0, ii = states.length; i < ii; i++) {
var state = states[i];
var key = state[0];
var value = state[1];
switch (key) {
case 'LW':
this.setLineWidth(value);
break;
case 'LC':
this.setLineCap(value);
break;
case 'LJ':
this.setLineJoin(value);
break;
case 'ML':
this.setMiterLimit(value);
break;
case 'D':
this.setDash(value[0], value[1]);
break;
case 'RI':
this.setRenderingIntent(value);
break;
case 'FL':
this.setFlatness(value);
break;
case 'Font':
this.setFont(state[1], state[2]);
break;
case 'CA':
this.current.strokeAlpha = state[1];
break;
case 'ca':
this.current.fillAlpha = state[1];
this.ctx.globalAlpha = state[1];
break;
}
}
},
save: function canvasGraphicsSave() {
this.ctx.save();
var old = this.current;
this.stateStack.push(old);
this.current = old.clone();
},
restore: function canvasGraphicsRestore() {
var prev = this.stateStack.pop();
if (prev) {
this.current = prev;
this.ctx.restore();
}
},
transform: function canvasGraphicsTransform(a, b, c, d, e, f) {
this.ctx.transform(a, b, c, d, e, f);
},
// Path
moveTo: function canvasGraphicsMoveTo(x, y) {
this.ctx.moveTo(x, y);
this.current.setCurrentPoint(x, y);
},
lineTo: function canvasGraphicsLineTo(x, y) {
this.ctx.lineTo(x, y);
this.current.setCurrentPoint(x, y);
},
curveTo: function canvasGraphicsCurveTo(x1, y1, x2, y2, x3, y3) {
this.ctx.bezierCurveTo(x1, y1, x2, y2, x3, y3);
this.current.setCurrentPoint(x3, y3);
},
curveTo2: function canvasGraphicsCurveTo2(x2, y2, x3, y3) {
var current = this.current;
this.ctx.bezierCurveTo(current.x, current.y, x2, y2, x3, y3);
current.setCurrentPoint(x3, y3);
},
curveTo3: function canvasGraphicsCurveTo3(x1, y1, x3, y3) {
this.curveTo(x1, y1, x3, y3, x3, y3);
this.current.setCurrentPoint(x3, y3);
},
closePath: function canvasGraphicsClosePath() {
this.ctx.closePath();
},
rectangle: function canvasGraphicsRectangle(x, y, width, height) {
this.ctx.rect(x, y, width, height);
},
stroke: function canvasGraphicsStroke(consumePath) {
consumePath = typeof consumePath !== 'undefined' ? consumePath : true;
var ctx = this.ctx;
var strokeColor = this.current.strokeColor;
// For stroke we want to temporarily change the global alpha to the
// stroking alpha.
ctx.globalAlpha = this.current.strokeAlpha;
if (strokeColor && strokeColor.hasOwnProperty('type') &&
strokeColor.type === 'Pattern') {
// for patterns, we transform to pattern space, calculate
// the pattern, call stroke, and restore to user space
ctx.save();
ctx.strokeStyle = strokeColor.getPattern(ctx);
ctx.stroke();
ctx.restore();
} else {
ctx.stroke();
}
if (consumePath)
this.consumePath();
// Restore the global alpha to the fill alpha
ctx.globalAlpha = this.current.fillAlpha;
},
closeStroke: function canvasGraphicsCloseStroke() {
this.closePath();
this.stroke();
},
fill: function canvasGraphicsFill(consumePath) {
consumePath = typeof consumePath !== 'undefined' ? consumePath : true;
var ctx = this.ctx;
var fillColor = this.current.fillColor;
if (fillColor && fillColor.hasOwnProperty('type') &&
fillColor.type === 'Pattern') {
ctx.save();
ctx.fillStyle = fillColor.getPattern(ctx);
ctx.fill();
ctx.restore();
} else {
ctx.fill();
}
if (consumePath)
this.consumePath();
},
eoFill: function canvasGraphicsEoFill() {
var savedFillRule = this.setEOFillRule();
this.fill();
this.restoreFillRule(savedFillRule);
},
fillStroke: function canvasGraphicsFillStroke() {
this.fill(false);
this.stroke(false);
this.consumePath();
},
eoFillStroke: function canvasGraphicsEoFillStroke() {
var savedFillRule = this.setEOFillRule();
this.fillStroke();
this.restoreFillRule(savedFillRule);
},
closeFillStroke: function canvasGraphicsCloseFillStroke() {
this.closePath();
this.fillStroke();
},
closeEOFillStroke: function canvasGraphicsCloseEOFillStroke() {
var savedFillRule = this.setEOFillRule();
this.closePath();
this.fillStroke();
this.restoreFillRule(savedFillRule);
},
endPath: function canvasGraphicsEndPath() {
this.consumePath();
},
// Clipping
clip: function canvasGraphicsClip() {
this.pendingClip = NORMAL_CLIP;
},
eoClip: function canvasGraphicsEoClip() {
this.pendingClip = EO_CLIP;
},
// Text
beginText: function canvasGraphicsBeginText() {
this.current.textMatrix = IDENTITY_MATRIX;
this.current.x = this.current.lineX = 0;
this.current.y = this.current.lineY = 0;
},
endText: function canvasGraphicsEndText() {
},
setCharSpacing: function canvasGraphicsSetCharSpacing(spacing) {
this.current.charSpacing = spacing;
},
setWordSpacing: function canvasGraphicsSetWordSpacing(spacing) {
this.current.wordSpacing = spacing;
},
setHScale: function canvasGraphicsSetHScale(scale) {
this.current.textHScale = scale / 100;
},
setLeading: function canvasGraphicsSetLeading(leading) {
this.current.leading = -leading;
},
setFont: function canvasGraphicsSetFont(fontRefName, size) {
var fontObj = this.objs.get(fontRefName).fontObj;
if (!fontObj) {
throw 'Can\'t find font for ' + fontRefName;
}
var name = fontObj.loadedName || 'sans-serif';
this.current.font = fontObj;
this.current.fontSize = size;
var name = fontObj.loadedName || 'sans-serif';
var bold = fontObj.black ? (fontObj.bold ? 'bolder' : 'bold') :
(fontObj.bold ? 'bold' : 'normal');
var italic = fontObj.italic ? 'italic' : 'normal';
var serif = fontObj.serif ? 'serif' : 'sans-serif';
var typeface = '"' + name + '", ' + serif;
var rule = italic + ' ' + bold + ' ' + size + 'px ' + typeface;
this.ctx.font = rule;
},
setTextRenderingMode: function canvasGraphicsSetTextRenderingMode(mode) {
if (mode >= TextRenderingMode.FILL_ADD_TO_PATH)
TODO('unsupported text rendering mode: ' + mode);
this.current.textRenderingMode = mode;
},
setTextRise: function canvasGraphicsSetTextRise(rise) {
TODO('text rise: ' + rise);
},
moveText: function canvasGraphicsMoveText(x, y) {
this.current.x = this.current.lineX += x;
this.current.y = this.current.lineY += y;
},
setLeadingMoveText: function canvasGraphicsSetLeadingMoveText(x, y) {
this.setLeading(-y);
this.moveText(x, y);
},
setTextMatrix: function canvasGraphicsSetTextMatrix(a, b, c, d, e, f) {
this.current.textMatrix = [a, b, c, d, e, f];
this.current.x = this.current.lineX = 0;
this.current.y = this.current.lineY = 0;
},
nextLine: function canvasGraphicsNextLine() {
this.moveText(0, this.current.leading);
},
applyTextTransforms: function canvasApplyTransforms() {
var ctx = this.ctx;
var current = this.current;
var textHScale = current.textHScale;
var fontMatrix = current.font.fontMatrix || IDENTITY_MATRIX;
ctx.transform.apply(ctx, current.textMatrix);
ctx.scale(1, -1);
ctx.translate(current.x, -1 * current.y);
ctx.transform.apply(ctx, fontMatrix);
ctx.scale(textHScale, 1);
},
getTextGeometry: function canvasGetTextGeometry() {
var geometry = {};
var ctx = this.ctx;
var font = this.current.font;
var ctxMatrix = ctx.mozCurrentTransform;
if (ctxMatrix) {
var bl = Util.applyTransform([0, 0], ctxMatrix);
var tr = Util.applyTransform([1, 1], ctxMatrix);
geometry.x = bl[0];
geometry.y = bl[1];
geometry.hScale = tr[0] - bl[0];
geometry.vScale = tr[1] - bl[1];
}
geometry.spaceWidth = font.spaceWidth;
return geometry;
},
pushTextDivs: function canvasGraphicsPushTextDivs(text) {
var div = document.createElement('div');
var fontSize = this.current.fontSize;
// vScale and hScale already contain the scaling to pixel units
// as mozCurrentTransform reflects ctx.scale() changes
// (see beginDrawing())
var fontHeight = fontSize * text.geom.vScale;
div.dataset.canvasWidth = text.canvasWidth * text.geom.hScale;
div.style.fontSize = fontHeight + 'px';
div.style.fontFamily = this.current.font.loadedName || 'sans-serif';
div.style.left = text.geom.x + 'px';
div.style.top = (text.geom.y - fontHeight) + 'px';
div.innerHTML = text.str;
div.dataset.textLength = text.length;
this.textDivs.push(div);
},
showText: function canvasGraphicsShowText(str, skipTextSelection) {
var ctx = this.ctx;
var current = this.current;
var font = current.font;
var glyphs = font.charsToGlyphs(str);
var fontSize = current.fontSize;
var charSpacing = current.charSpacing;
var wordSpacing = current.wordSpacing;
var textHScale = current.textHScale;
var fontMatrix = font.fontMatrix || IDENTITY_MATRIX;
var textHScale2 = textHScale * fontMatrix[0];
var glyphsLength = glyphs.length;
var textLayer = this.textLayer;
var text = {str: '', length: 0, canvasWidth: 0, geom: {}};
var textSelection = textLayer && !skipTextSelection ? true : false;
var textRenderingMode = current.textRenderingMode;
// Type3 fonts - each glyph is a "mini-PDF"
if (font.coded) {
ctx.save();
ctx.transform.apply(ctx, current.textMatrix);
ctx.translate(current.x, current.y);
ctx.scale(textHScale, 1);
if (textSelection) {
this.save();
ctx.scale(1, -1);
text.geom = this.getTextGeometry();
this.restore();
}
for (var i = 0; i < glyphsLength; ++i) {
var glyph = glyphs[i];
if (glyph === null) {
// word break
this.ctx.translate(wordSpacing, 0);
continue;
}
this.save();
ctx.scale(fontSize, fontSize);
ctx.transform.apply(ctx, fontMatrix);
this.executeIRQueue(glyph.codeIRQueue);
this.restore();
var transformed = Util.applyTransform([glyph.width, 0], fontMatrix);
var width = transformed[0] * fontSize + charSpacing;
ctx.translate(width, 0);
current.x += width * textHScale;
text.str += glyph.unicode;
text.length++;
text.canvasWidth += width;
}
ctx.restore();
} else {
ctx.save();
this.applyTextTransforms();
if (textSelection)
text.geom = this.getTextGeometry();
var width = 0;
for (var i = 0; i < glyphsLength; ++i) {
var glyph = glyphs[i];
if (glyph === null) {
// word break
width += wordSpacing;
continue;
}
var char = glyph.fontChar;
var charWidth = glyph.width * fontSize * 0.001 + charSpacing;
switch (textRenderingMode) {
default: // other unsupported rendering modes
case TextRenderingMode.FILL:
case TextRenderingMode.FILL_ADD_TO_PATH:
ctx.fillText(char, width, 0);
break;
case TextRenderingMode.STROKE:
case TextRenderingMode.STROKE_ADD_TO_PATH:
ctx.strokeText(char, width, 0);
break;
case TextRenderingMode.FILL_STROKE:
case TextRenderingMode.FILL_STROKE_ADD_TO_PATH:
ctx.fillText(char, width, 0);
ctx.strokeText(char, width, 0);
break;
case TextRenderingMode.INVISIBLE:
break;
}
width += charWidth;
text.str += glyph.unicode === ' ' ? '&nbsp;' : glyph.unicode;
text.length++;
text.canvasWidth += charWidth;
}
current.x += width * textHScale2;
ctx.restore();
}
if (textSelection)
this.pushTextDivs(text);
return text;
},
showSpacedText: function canvasGraphicsShowSpacedText(arr) {
var ctx = this.ctx;
var current = this.current;
var font = current.font;
var fontSize = current.fontSize;
var textHScale = current.textHScale;
if (!font.coded)
textHScale *= (font.fontMatrix || IDENTITY_MATRIX)[0];
var arrLength = arr.length;
var textLayer = this.textLayer;
var text = {str: '', length: 0, canvasWidth: 0, geom: {}};
var textSelection = textLayer ? true : false;
if (textSelection) {
ctx.save();
// Type3 fonts - each glyph is a "mini-PDF" (see also showText)
if (font.coded) {
ctx.transform.apply(ctx, current.textMatrix);
ctx.scale(1, -1);
ctx.translate(current.x, -1 * current.y);
ctx.scale(textHScale, 1);
} else
this.applyTextTransforms();
text.geom = this.getTextGeometry();
ctx.restore();
}
for (var i = 0; i < arrLength; ++i) {
var e = arr[i];
if (isNum(e)) {
var spacingLength = -e * 0.001 * fontSize * textHScale;
current.x += spacingLength;
if (textSelection) {
// Emulate precise spacing via HTML spaces
text.canvasWidth += spacingLength;
if (e < 0 && text.geom.spaceWidth > 0) { // avoid div by zero
var numFakeSpaces = Math.round(-e / text.geom.spaceWidth);
if (numFakeSpaces > 0) {
text.str += '&nbsp;';
text.length++;
}
}
}
} else if (isString(e)) {
var shownText = this.showText(e, true);
if (textSelection) {
if (shownText.str === ' ') {
text.str += '&nbsp;';
} else {
text.str += shownText.str;
}
text.canvasWidth += shownText.canvasWidth;
text.length += e.length;
}
} else {
malformed('TJ array element ' + e + ' is not string or num');
}
}
if (textSelection)
this.pushTextDivs(text);
},
nextLineShowText: function canvasGraphicsNextLineShowText(text) {
this.nextLine();
this.showText(text);
},
nextLineSetSpacingShowText:
function canvasGraphicsNextLineSetSpacingShowText(wordSpacing,
charSpacing,
text) {
this.setWordSpacing(wordSpacing);
this.setCharSpacing(charSpacing);
this.nextLineShowText(text);
},
// Type3 fonts
setCharWidth: function canvasGraphicsSetCharWidth(xWidth, yWidth) {
// We can safely ignore this since the width should be the same
// as the width in the Widths array.
},
setCharWidthAndBounds: function canvasGraphicsSetCharWidthAndBounds(xWidth,
yWidth,
llx,
lly,
urx,
ury) {
// TODO According to the spec we're also suppose to ignore any operators
// that set color or include images while processing this type3 font.
this.rectangle(llx, lly, urx - llx, ury - lly);
this.clip();
this.endPath();
},
// Color
setStrokeColorSpace: function canvasGraphicsSetStrokeColorSpace(raw) {
this.current.strokeColorSpace = ColorSpace.fromIR(raw);
},
setFillColorSpace: function canvasGraphicsSetFillColorSpace(raw) {
this.current.fillColorSpace = ColorSpace.fromIR(raw);
},
setStrokeColor: function canvasGraphicsSetStrokeColor(/*...*/) {
var cs = this.current.strokeColorSpace;
var color = cs.getRgb(arguments);
var color = Util.makeCssRgb.apply(null, cs.getRgb(arguments));
this.ctx.strokeStyle = color;
this.current.strokeColor = color;
},
getColorN_IR_Pattern: function canvasGraphicsGetColorN_IR_Pattern(IR, cs) {
if (IR[0] == 'TilingPattern') {
var args = IR[1];
var base = cs.base;
var color;
if (base) {
var baseComps = base.numComps;
color = [];
for (var i = 0; i < baseComps; ++i)
color.push(args[i]);
color = base.getRgb(color);
}
var pattern = new TilingPattern(IR, color, this.ctx, this.objs);
} else if (IR[0] == 'RadialAxial' || IR[0] == 'Dummy') {
var pattern = Pattern.shadingFromIR(this.ctx, IR);
} else {
throw 'Unkown IR type';
}
return pattern;
},
setStrokeColorN_IR: function canvasGraphicsSetStrokeColorN(/*...*/) {
var cs = this.current.strokeColorSpace;
if (cs.name == 'Pattern') {
this.current.strokeColor = this.getColorN_IR_Pattern(arguments, cs);
} else {
this.setStrokeColor.apply(this, arguments);
}
},
setFillColor: function canvasGraphicsSetFillColor(/*...*/) {
var cs = this.current.fillColorSpace;
var color = Util.makeCssRgb.apply(null, cs.getRgb(arguments));
this.ctx.fillStyle = color;
this.current.fillColor = color;
},
setFillColorN_IR: function canvasGraphicsSetFillColorN(/*...*/) {
var cs = this.current.fillColorSpace;
if (cs.name == 'Pattern') {
this.current.fillColor = this.getColorN_IR_Pattern(arguments, cs);
} else {
this.setFillColor.apply(this, arguments);
}
},
setStrokeGray: function canvasGraphicsSetStrokeGray(gray) {
if (!(this.current.strokeColorSpace instanceof DeviceGrayCS))
this.current.strokeColorSpace = new DeviceGrayCS();
var color = Util.makeCssRgb(gray, gray, gray);
this.ctx.strokeStyle = color;
this.current.strokeColor = color;
},
setFillGray: function canvasGraphicsSetFillGray(gray) {
if (!(this.current.fillColorSpace instanceof DeviceGrayCS))
this.current.fillColorSpace = new DeviceGrayCS();
var color = Util.makeCssRgb(gray, gray, gray);
this.ctx.fillStyle = color;
this.current.fillColor = color;
},
setStrokeRGBColor: function canvasGraphicsSetStrokeRGBColor(r, g, b) {
if (!(this.current.strokeColorSpace instanceof DeviceRgbCS))
this.current.strokeColorSpace = new DeviceRgbCS();
var color = Util.makeCssRgb(r, g, b);
this.ctx.strokeStyle = color;
this.current.strokeColor = color;
},
setFillRGBColor: function canvasGraphicsSetFillRGBColor(r, g, b) {
if (!(this.current.fillColorSpace instanceof DeviceRgbCS))
this.current.fillColorSpace = new DeviceRgbCS();
var color = Util.makeCssRgb(r, g, b);
this.ctx.fillStyle = color;
this.current.fillColor = color;
},
setStrokeCMYKColor: function canvasGraphicsSetStrokeCMYKColor(c, m, y, k) {
if (!(this.current.strokeColorSpace instanceof DeviceCmykCS))
this.current.strokeColorSpace = new DeviceCmykCS();
var color = Util.makeCssCmyk(c, m, y, k);
this.ctx.strokeStyle = color;
this.current.strokeColor = color;
},
setFillCMYKColor: function canvasGraphicsSetFillCMYKColor(c, m, y, k) {
if (!(this.current.fillColorSpace instanceof DeviceCmykCS))
this.current.fillColorSpace = new DeviceCmykCS();
var color = Util.makeCssCmyk(c, m, y, k);
this.ctx.fillStyle = color;
this.current.fillColor = color;
},
shadingFill: function canvasGraphicsShadingFill(patternIR) {
var ctx = this.ctx;
this.save();
ctx.fillStyle = Pattern.shadingFromIR(ctx, patternIR);
var inv = ctx.mozCurrentTransformInverse;
if (inv) {
var canvas = ctx.canvas;
var width = canvas.width;
var height = canvas.height;
var bl = Util.applyTransform([0, 0], inv);
var br = Util.applyTransform([0, height], inv);
var ul = Util.applyTransform([width, 0], inv);
var ur = Util.applyTransform([width, height], inv);
var x0 = Math.min(bl[0], br[0], ul[0], ur[0]);
var y0 = Math.min(bl[1], br[1], ul[1], ur[1]);
var x1 = Math.max(bl[0], br[0], ul[0], ur[0]);
var y1 = Math.max(bl[1], br[1], ul[1], ur[1]);
this.ctx.fillRect(x0, y0, x1 - x0, y1 - y0);
} else {
// HACK to draw the gradient onto an infinite rectangle.
// PDF gradients are drawn across the entire image while
// Canvas only allows gradients to be drawn in a rectangle
// The following bug should allow us to remove this.
// https://bugzilla.mozilla.org/show_bug.cgi?id=664884
this.ctx.fillRect(-1e10, -1e10, 2e10, 2e10);
}
this.restore();
},
// Images
beginInlineImage: function canvasGraphicsBeginInlineImage() {
error('Should not call beginInlineImage');
},
beginImageData: function canvasGraphicsBeginImageData() {
error('Should not call beginImageData');
},
paintFormXObjectBegin: function canvasGraphicsPaintFormXObjectBegin(matrix,
bbox) {
this.save();
if (matrix && isArray(matrix) && 6 == matrix.length)
this.transform.apply(this, matrix);
if (bbox && isArray(bbox) && 4 == bbox.length) {
var width = bbox[2] - bbox[0];
var height = bbox[3] - bbox[1];
this.rectangle(bbox[0], bbox[1], width, height);
this.clip();
this.endPath();
}
},
paintFormXObjectEnd: function canvasGraphicsPaintFormXObjectEnd() {
this.restore();
},
paintJpegXObject: function canvasGraphicsPaintJpegXObject(objId, w, h) {
var domImage = this.objs.get(objId);
if (!domImage) {
error('Dependent image isn\'t ready yet');
}
this.save();
var ctx = this.ctx;
// scale the image to the unit square
ctx.scale(1 / w, -1 / h);
ctx.drawImage(domImage, 0, 0, domImage.width, domImage.height,
0, -h, w, h);
this.restore();
},
paintImageMaskXObject: function canvasGraphicsPaintImageMaskXObject(
imgArray, inverseDecode, width, height) {
function applyStencilMask(buffer, inverseDecode) {
var imgArrayPos = 0;
var i, j, mask, buf;
// removing making non-masked pixels transparent
var bufferPos = 3; // alpha component offset
for (i = 0; i < height; i++) {
mask = 0;
for (j = 0; j < width; j++) {
if (!mask) {
buf = imgArray[imgArrayPos++];
mask = 128;
}
if (!(buf & mask) == inverseDecode) {
buffer[bufferPos] = 0;
}
bufferPos += 4;
mask >>= 1;
}
}
}
this.save();
var ctx = this.ctx;
var w = width, h = height;
// scale the image to the unit square
ctx.scale(1 / w, -1 / h);
var tmpCanvas = new this.ScratchCanvas(w, h);
var tmpCtx = tmpCanvas.getContext('2d');
var fillColor = this.current.fillColor;
tmpCtx.fillStyle = (fillColor && fillColor.hasOwnProperty('type') &&
fillColor.type === 'Pattern') ?
fillColor.getPattern(tmpCtx) : fillColor;
tmpCtx.fillRect(0, 0, w, h);
var imgData = tmpCtx.getImageData(0, 0, w, h);
var pixels = imgData.data;
applyStencilMask(pixels, inverseDecode);
tmpCtx.putImageData(imgData, 0, 0);
ctx.drawImage(tmpCanvas, 0, -h);
this.restore();
},
paintImageXObject: function canvasGraphicsPaintImageXObject(objId) {
var imgData = this.objs.get(objId);
if (!imgData) {
error('Dependent image isn\'t ready yet');
}
this.save();
var ctx = this.ctx;
var w = imgData.width;
var h = imgData.height;
// scale the image to the unit square
ctx.scale(1 / w, -1 / h);
var tmpCanvas = new this.ScratchCanvas(w, h);
var tmpCtx = tmpCanvas.getContext('2d');
this.putBinaryImageData(tmpCtx, imgData, w, h);
ctx.drawImage(tmpCanvas, 0, -h);
this.restore();
},
putBinaryImageData: function canvasPutBinaryImageData() {
//
},
// Marked content
markPoint: function canvasGraphicsMarkPoint(tag) {
TODO('Marked content');
},
markPointProps: function canvasGraphicsMarkPointProps(tag, properties) {
TODO('Marked content');
},
beginMarkedContent: function canvasGraphicsBeginMarkedContent(tag) {
TODO('Marked content');
},
beginMarkedContentProps:
function canvasGraphicsBeginMarkedContentProps(tag, properties) {
TODO('Marked content');
},
endMarkedContent: function canvasGraphicsEndMarkedContent() {
TODO('Marked content');
},
// Compatibility
beginCompat: function canvasGraphicsBeginCompat() {
TODO('ignore undefined operators (should we do that anyway?)');
},
endCompat: function canvasGraphicsEndCompat() {
TODO('stop ignoring undefined operators');
},
// Helper functions
consumePath: function canvasGraphicsConsumePath() {
if (this.pendingClip) {
var savedFillRule = null;
if (this.pendingClip == EO_CLIP)
savedFillRule = this.setEOFillRule();
this.ctx.clip();
this.pendingClip = null;
if (savedFillRule !== null)
this.restoreFillRule(savedFillRule);
}
this.ctx.beginPath();
},
// We generally keep the canvas context set for
// nonzero-winding, and just set evenodd for the operations
// that need them.
setEOFillRule: function canvasGraphicsSetEOFillRule() {
var savedFillRule = this.ctx.mozFillRule;
this.ctx.mozFillRule = 'evenodd';
return savedFillRule;
},
restoreFillRule: function canvasGraphicsRestoreFillRule(rule) {
this.ctx.mozFillRule = rule;
}
};
return CanvasGraphics;
})();
if (!isWorker) {
// Feature detection if the browser can use an Uint8Array directly as imgData.
var canvas = document.createElement('canvas');
canvas.width = 1;
canvas.height = 1;
var ctx = canvas.getContext('2d');
try {
ctx.putImageData({
width: 1,
height: 1,
data: new Uint8Array(4)
}, 0, 0);
CanvasGraphics.prototype.putBinaryImageData =
function CanvasGraphicsPutBinaryImageDataNative(ctx, imgData) {
ctx.putImageData(imgData, 0, 0);
};
} catch (e) {
CanvasGraphics.prototype.putBinaryImageData =
function CanvasGraphicsPutBinaryImageDataShim(ctx, imgData, w, h) {
var tmpImgData = ctx.getImageData(0, 0, w, h);
// Copy over the imageData pixel by pixel.
var tmpImgDataPixels = tmpImgData.data;
var len = tmpImgDataPixels.length;
while (len--) {
tmpImgDataPixels[len] = imgData.data[len];
}
ctx.putImageData(tmpImgData, 0, 0);
};
}
}