ZenBrowserMirrors/pdf.js
1
0
Fork 0
mirror of https://github.com/zen-browser/pdf.js.git synced 2025-07-10 10:15:37 +02:00
Code Issues Projects Releases Packages Wiki Activity Actions

Use a more compact typed array to pass the image mask from the worker to the main thread.

Browse source
This commit is contained in:
Nicholas Nethercote 2014-01-13 20:08:39 -06:00 • committed by Yury Delendik
parent dabafb8444
commit 3f533a1cb0
3 changed files with 44 additions and 22 deletions
Download patch file Download diff file Expand all files Collapse all files

32
src/display/canvas.js
View file

@ -431,6 +431,34 @@ var CanvasGraphics = (function CanvasGraphicsClosure() {
ctx.putImageData(tmpImgData, 0, 0);
}
function putBinaryImageMask(ctx, imgData) {
var width = imgData.width, height = imgData.height;
var tmpImgData = ctx.createImageData(width, height);
var data = imgData.data;
var tmpImgDataPixels = tmpImgData.data;
var dataPos = 0;
// Expand the mask so it can be used by the canvas. Any required inversion
// has already been handled.
var tmpPos = 3; // alpha component offset
for (var i = 0; i < height; i++) {
var mask = 0;
for (var j = 0; j < width; j++) {
if (!mask) {
var elem = data[dataPos++];
mask = 128;
}
if (!(elem & mask)) {
tmpImgDataPixels[tmpPos] = 255;
}
tmpPos += 4;
mask >>= 1;
}
}
ctx.putImageData(tmpImgData, 0, 0);
}
function copyCtxState(sourceCtx, destCtx) {
var properties = ['strokeStyle', 'fillStyle', 'fillRule', 'globalAlpha',
'lineWidth', 'lineCap', 'lineJoin', 'miterLimit',
@ -1611,7 +1639,7 @@ var CanvasGraphics = (function CanvasGraphicsClosure() {
var maskCtx = maskCanvas.context;
maskCtx.save();
putBinaryImageData(maskCtx, img);
putBinaryImageMask(maskCtx, img);
maskCtx.globalCompositeOperation = 'source-in';
@ -1638,7 +1666,7 @@ var CanvasGraphics = (function CanvasGraphicsClosure() {
var maskCtx = maskCanvas.context;
maskCtx.save();
putBinaryImageData(maskCtx, image);
putBinaryImageMask(maskCtx, image);
maskCtx.globalCompositeOperation = 'source-in';