Sakurai/pdf.js
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

Suspending/resuming SMask operation during setGState/restore.

Browse Source
This commit is contained in:
Yury Delendik 2016-04-09 18:46:15 -05:00
parent 1c253e6e1d
commit 1485c1d1da
1 changed files with 75 additions and 8 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

83
src/display/canvas.js
View File

@ -432,7 +432,8 @@ var CanvasExtraState = (function CanvasExtraStateClosure() {
this.fillAlpha = 1;
this.strokeAlpha = 1;
this.lineWidth = 1;
this.activeSMask = null; // nonclonable field (see the save method below)
this.activeSMask = null;
this.resumeSMaskCtx = null; // nonclonable field (see the save method below)
this.old = old;
}
@ -977,7 +978,16 @@ var CanvasGraphics = (function CanvasGraphicsClosure() {
break;
case 'SMask':
if (this.current.activeSMask) {
this.endSMaskGroup();
// If SMask is currrenly used, it needs to be suspended or
// finished. Suspend only makes sense when at least one save()
// was performed and state needs to be reverted on restore().
if (this.stateStack.length > 0 &&
(this.stateStack[this.stateStack.length - 1].activeSMask ===
this.current.activeSMask)) {
this.suspendSMaskGroup();
} else {
this.endSMaskGroup();
}
}
this.current.activeSMask = value ? this.tempSMask : null;
if (this.current.activeSMask) {
@ -1006,6 +1016,8 @@ var CanvasGraphics = (function CanvasGraphicsClosure() {
groupCtx.translate(-activeSMask.offsetX, -activeSMask.offsetY);
groupCtx.transform.apply(groupCtx, currentTransform);
activeSMask.startTransformInverse = groupCtx.mozCurrentTransformInverse;
copyCtxState(currentCtx, groupCtx);
this.ctx = groupCtx;
this.setGState([
@ -1016,6 +1028,43 @@ var CanvasGraphics = (function CanvasGraphicsClosure() {
this.groupStack.push(currentCtx);
this.groupLevel++;
},
suspendSMaskGroup: function CanvasGraphics_endSMaskGroup() {
// Similar to endSMaskGroup, the intermediate canvas has to be composed
// and future ctx state restored.
var groupCtx = this.ctx;
this.groupLevel--;
this.ctx = this.groupStack.pop();
composeSMask(this.ctx, this.current.activeSMask, groupCtx);
this.ctx.restore();
this.ctx.save(); // save is needed since SMask will be resumed.
copyCtxState(groupCtx, this.ctx);
// Saving state for resuming.
this.current.resumeSMaskCtx = groupCtx;
// Transform was changed in the SMask canvas, reflecting this change on
// this.ctx.
var deltaTransform = Util.transform(
this.current.activeSMask.startTransformInverse,
groupCtx.mozCurrentTransform);
this.ctx.transform.apply(this.ctx, deltaTransform);
// SMask was composed, the results at the groupCtx can be cleared.
groupCtx.save();
groupCtx.setTransform(1, 0, 0, 1, 0, 0);
groupCtx.clearRect(0, 0, groupCtx.canvas.width, groupCtx.canvas.height);
groupCtx.restore();
},
resumeSMaskGroup: function CanvasGraphics_endSMaskGroup() {
// Resuming state saved by suspendSMaskGroup. We don't need to restore
// any groupCtx state since restore() command (the only caller) will do
// that for us. See also beginSMaskGroup.
var groupCtx = this.current.resumeSMaskCtx;
var currentCtx = this.ctx;
this.ctx = groupCtx;
this.groupStack.push(currentCtx);
this.groupLevel++;
},
endSMaskGroup: function CanvasGraphics_endSMaskGroup() {
var groupCtx = this.ctx;
this.groupLevel--;
@ -1024,20 +1073,34 @@ var CanvasGraphics = (function CanvasGraphicsClosure() {
composeSMask(this.ctx, this.current.activeSMask, groupCtx);
this.ctx.restore();
copyCtxState(groupCtx, this.ctx);
// Transform was changed in the SMask canvas, reflecting this change on
// this.ctx.
var deltaTransform = Util.transform(
this.current.activeSMask.startTransformInverse,
groupCtx.mozCurrentTransform);
this.ctx.transform.apply(this.ctx, deltaTransform);
},
save: function CanvasGraphics_save() {
this.ctx.save();
var old = this.current;
this.stateStack.push(old);
this.current = old.clone();
this.current.activeSMask = null;
this.current.resumeSMaskCtx = null;
},
restore: function CanvasGraphics_restore() {
if (this.stateStack.length !== 0) {
if (this.current.activeSMask !== null) {
this.endSMaskGroup();
}
// SMask was suspended, we just need to resume it.
if (this.current.resumeSMaskCtx) {
this.resumeSMaskGroup();
}
// SMask has to be finished once there is no states that are using the
// same SMask.
if (this.current.activeSMask !== null && (this.stateStack.length === 0 ||
this.stateStack[this.stateStack.length - 1].activeSMask !==
this.current.activeSMask)) {
this.endSMaskGroup();
}
if (this.stateStack.length !== 0) {
this.current = this.stateStack.pop();
this.ctx.restore();
@ -1825,7 +1888,8 @@ var CanvasGraphics = (function CanvasGraphicsClosure() {
scaleY: scaleY,
subtype: group.smask.subtype,
backdrop: group.smask.backdrop,
transferMap: group.smask.transferMap || null
transferMap: group.smask.transferMap || null,
startTransformInverse: null, // used during suspend operation
});
} else {
// Setup the current ctx so when the group is popped we draw it at the
@ -1845,6 +1909,9 @@ var CanvasGraphics = (function CanvasGraphicsClosure() {
]);
this.groupStack.push(currentCtx);
this.groupLevel++;
// Reseting mask state, masks will be applied on restore of the group.
this.current.activeSMask = null;
},
endGroup: function CanvasGraphics_endGroup(group) {