From bce760148081d955c227df9df72fdc34edf53886 Mon Sep 17 00:00:00 2001
From: Nicholas Nethercote <nnethercote@mozilla.com>
Date: Wed, 18 Jun 2014 06:59:52 -0700
Subject: [PATCH] Build up textChunk.str more efficiently.
PartialEvaluator.getTextContent() builds up textChunk strings 1 char at a time,
creating many 100s of 1000s of intermediate strings along the way. This patch
make it instead push chars to an array and then join them at the end, as we
have done in numerous other places.
---
src/core/evaluator.js | 13 ++++++++-----
1 file changed, 8 insertions(+), 5 deletions(-)
diff --git a/src/core/evaluator.js b/src/core/evaluator.js
index be8900d49..65365aa8a 100644
--- a/src/core/evaluator.js
+++ b/src/core/evaluator.js
@@ -908,7 +908,9 @@ var PartialEvaluator = (function PartialEvaluatorClosure() {
};
}
return {
- str: '',
+ // |str| is initially an array which we push individual chars to, and
+ // then runBidi() overwrites it with the final string.
+ str: [],
dir: null,
width: 0,
height: 0,
@@ -918,7 +920,8 @@ var PartialEvaluator = (function PartialEvaluatorClosure() {
}
function runBidi(textChunk) {
- var bidiResult = PDFJS.bidi(textChunk.str, -1, textState.font.vertical);
+ var str = textChunk.str.join('');
+ var bidiResult = PDFJS.bidi(str, -1, textState.font.vertical);
textChunk.str = bidiResult.str;
textChunk.dir = bidiResult.dir;
return textChunk;
@@ -1008,7 +1011,7 @@ var PartialEvaluator = (function PartialEvaluatorClosure() {
}
textState.translateTextMatrix(tx, ty);
- textChunk.str += glyphUnicode;
+ textChunk.str.push(glyphUnicode);
}
var a = textState.textLineMatrix[0];
@@ -1103,10 +1106,10 @@ var PartialEvaluator = (function PartialEvaluatorClosure() {
if (fakeSpaces > MULTI_SPACE_FACTOR) {
fakeSpaces = Math.round(fakeSpaces);
while (fakeSpaces--) {
- textChunk.str += ' ';
+ textChunk.str.push(' ');
}
} else if (fakeSpaces > SPACE_FACTOR) {
- textChunk.str += ' ';
+ textChunk.str.push(' ');
}
}
}