Merge pull request #14096 from Snuffleupagus/spreadMode-preRender

Pre-render *one* additional page when spreadModes are enabled
This commit is contained in:
Tim van der Meij 2021-10-02 12:54:19 +02:00 committed by GitHub
commit dedff3c982
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2 changed files with 23 additions and 16 deletions

View File

@ -1250,10 +1250,16 @@ class BaseViewer {
const scrollAhead = this._isScrollModeHorizontal
? this.scroll.right
: this.scroll.down;
const preRenderExtra =
this._scrollMode === ScrollMode.VERTICAL &&
this._spreadMode !== SpreadMode.NONE &&
!this.isInPresentationMode;
const pageView = this.renderingQueue.getHighestPriority(
visiblePages,
this._pages,
scrollAhead
scrollAhead,
preRenderExtra
);
if (pageView) {
this._ensurePdfPageLoaded(pageView).then(() => {

View File

@ -102,8 +102,9 @@ class PDFRenderingQueue {
* @param {Object} visible
* @param {Array} views
* @param {boolean} scrolledDown
* @param {boolean} [preRenderExtra]
*/
getHighestPriority(visible, views, scrolledDown) {
getHighestPriority(visible, views, scrolledDown, preRenderExtra = false) {
/**
* The state has changed. Figure out which page has the highest priority to
* render next (if any).
@ -126,20 +127,20 @@ class PDFRenderingQueue {
}
}
// All the visible views have rendered; try to render next/previous pages.
if (scrolledDown) {
const nextPageIndex = visible.last.id;
// IDs start at 1, so no need to add 1.
if (views[nextPageIndex] && !this.isViewFinished(views[nextPageIndex])) {
return views[nextPageIndex];
}
} else {
const previousPageIndex = visible.first.id - 2;
if (
views[previousPageIndex] &&
!this.isViewFinished(views[previousPageIndex])
) {
return views[previousPageIndex];
// All the visible views have rendered; try to render next/previous page.
// (IDs start at 1, so no need to add 1 when `scrolledDown === true`.)
let preRenderIndex = scrolledDown ? visible.last.id : visible.first.id - 2;
let preRenderView = views[preRenderIndex];
if (preRenderView && !this.isViewFinished(preRenderView)) {
return preRenderView;
}
if (preRenderExtra) {
preRenderIndex += scrolledDown ? 1 : -1;
preRenderView = views[preRenderIndex];
if (preRenderView && !this.isViewFinished(preRenderView)) {
return preRenderView;
}
}
// Everything that needs to be rendered has been.