public void setPage(int pageNum) {
page = pageNum;
DjVuPage newPage = app.getPageCache().fetchPage(pageNum);
if (newPage != null) {
pageInfo = newPage.getInfo();
app.getToolbar().setZoomOptions(findZoomOptions());
viewChanged();
} else {
pageInfo = null;
}
redraw();
if (changeListener != null) changeListener.pageChanged(pageNum);
scheduleURLUpdate();
}
private ArrayList<Integer> findZoomOptions() {
ArrayList<Integer> result = new ArrayList<>();
result.add(100);
final int screenDPI = app.getScreenDPI();
zoom100 = 1.0 * screenDPI / pageInfo.dpi;
int subsample = toSubsample(zoom100);
if (toZoom(subsample) / zoom100 > zoom100 / toZoom(subsample + 1)) subsample++;
zoom100 = toZoom(subsample);
if (zoom == 0) zoom = zoom100;
double z = zoom100;
for (int i = subsample + 1; i <= MAX_SUBSAMPLE; i++) {
double z2 = toZoom(i);
if (z / z2 > 1.2) {
z = z2;
result.add((int) (z / zoom100 * 100 + 0.5));
}
}
z = zoom100;
for (int i = subsample - 1; i >= 1; i--) {
double z2 = toZoom(i);
if (z2 / z > 1.2) {
z = z2;
result.add(0, (int) (z / zoom100 * 100 + 0.5));
}
}
return result;
}
public SinglePageLayout(Djvu_html5 app) {
this.app = app;
this.tileCache = app.getTileCache();
this.pageCache = app.getPageCache();
pageCache.addFullDecodeListener(this);
tileCache.addTileCacheListener(this);
this.canvas = app.getCanvas();
this.background = app.getBackground();
this.pageMargin = app.getPageMargin();
new PanController();
boolean pageParam = false;
try {
page = Integer.parseInt(Window.Location.getParameter("p")) - 1;
pageParam = true;
} catch (Exception e) {
page = 0;
}
locationUpdateEnabled = pageParam || app.getLocationUpdateEnabled();
pageCache.fetchPage(page);
}
private void viewChanged() {
if (pageInfo == null) return;
int w = canvas.getCoordinateSpaceWidth(), h = canvas.getCoordinateSpaceHeight();
int pw = (int) (pageInfo.width * zoom), ph = (int) (pageInfo.height * zoom);
if (pw < w) {
centerX = pw / 2;
} else {
centerX = Math.max(centerX, w / 2 - pageMargin);
centerX = Math.min(centerX, pw - w / 2 + pageMargin);
}
if (ph < h) {
centerY = ph / 2;
} else {
centerY = Math.max(centerY, h / 2 - pageMargin);
centerY = Math.min(centerY, ph - h / 2 + pageMargin);
}
double pw2 = pw + 2 * pageMargin, ph2 = ph + 2 * pageMargin;
app.getHorizontalScrollbar().setThumb((centerX + pageMargin) / pw2, w / pw2);
app.getVerticalScrollbar().setThumb((centerY + pageMargin) / ph2, h / ph2);
if (app.getTextLayer() != null)
app.getTextLayer().setViewPosition(page, w / 2 - centerX, h / 2 - centerY, zoom);
}
