mirrors/pdf.js
1
0
Fork 0
mirror of https://github.com/mozilla/pdf.js.git synced 2025-04-26 01:58:06 +02:00
Code Activity

Improve caching of shading patterns. (bug 1721949)

Browse source 
The PDF in bug 1721949 uses many unique pattern objects
that references the same shading many times. This caused
a new canvas pattern to be created and cached many times
driving up memory use.

To fix, I've changed the cache in the worker to key off the
shading object and instead send the shading and matrix
separately. While that worked well to fix the above bug,
there could be PDFs that use many shading that could
cause memory issues, so I've also added a LRU cache
on the main thread for canvas patterns. This should prevent
memory use from getting too high.
This commit is contained in:
Brendan Dahl 2021-07-27 19:58:06 -07:00
parent 777d890268
commit c836e1f0fb
4 changed files with 85 additions and 60 deletions
Download patch file Download diff file Expand all files Collapse all files

28
src/core/pattern.js
View file

@ -44,7 +44,6 @@ class Pattern {
static parseShading(
shading,
matrix,
xref,
res,
handler,
@ -60,7 +59,6 @@ class Pattern {
case ShadingType.RADIAL:
return new RadialAxialShading(
dict,
matrix,
xref,
res,
pdfFunctionFactory,
@ -72,7 +70,6 @@ class Pattern {
case ShadingType.TENSOR_PATCH_MESH:
return new MeshShading(
shading,
matrix,
xref,
res,
pdfFunctionFactory,
@ -115,16 +112,8 @@ class BaseShading {
// Radial and axial shading have very similar implementations
// If needed, the implementations can be broken into two classes.
class RadialAxialShading extends BaseShading {
constructor(
dict,
matrix,
xref,
resources,
pdfFunctionFactory,
localColorSpaceCache
) {
constructor(dict, xref, resources, pdfFunctionFactory, localColorSpaceCache) {
super();
this.matrix = matrix;
this.coordsArr = dict.getArray("Coords");
this.shadingType = dict.get("ShadingType");
const cs = ColorSpace.parse({
@ -244,17 +233,7 @@ class RadialAxialShading extends BaseShading {
unreachable(`getPattern type unknown: ${shadingType}`);
}
return [
"RadialAxial",
type,
this.bbox,
this.colorStops,
p0,
p1,
r0,
r1,
this.matrix,
];
return ["RadialAxial", type, this.bbox, this.colorStops, p0, p1, r0, r1];
}
}
@ -418,7 +397,6 @@ class MeshShading extends BaseShading {
constructor(
stream,
matrix,
xref,
resources,
pdfFunctionFactory,
@ -429,7 +407,6 @@ class MeshShading extends BaseShading {
throw new FormatError("Mesh data is not a stream");
}
const dict = stream.dict;
this.matrix = matrix;
this.shadingType = dict.get("ShadingType");
const bbox = dict.getArray("BBox");
if (Array.isArray(bbox) && bbox.length === 4) {
@ -942,7 +919,6 @@ class MeshShading extends BaseShading {
this.colors,
this.figures,
this.bounds,
this.matrix,
this.bbox,
this.background,
];