Maintain zoom level and center on window / viewer resize

Is it possible to maintain zoom level and center of viewport when we scaling browser window / viewer size? I have an application which need to keep zoom level and center remain same even when users resize the window, because my application synchronize OSD viewport to all connected users trough socket.io. It is look strange when there is user who resize window then send signal zoom and pan in OSD resize event way and will give unnecessary disrupt other users viewport.

[avandecreme]

The relevant code is here https://github.com/openseadragon/openseadragon/blob/master/src/viewer.js#L2988-L3009

It doesn’t look like there is a good event you can listen to to tweak the behavior. For now, you can try to modify that code like this and see if that works for you. We can figure out a better approach afterward.

    if (viewer.autoResize) {
        var containerSize = _getSafeElemSize(viewer.container);
        var prevContainerSize = THIS[viewer.hash].prevContainerSize;
        if (!containerSize.equals(prevContainerSize)) {
            var viewport = viewer.viewport;
            var center = viewport.getCenter();
            viewport.resize(containerSize, false);
            viewport.panTo(center, true);
            THIS[viewer.hash].prevContainerSize = containerSize;
            THIS[viewer.hash].forceRedraw = true;
        }
    }

[bayucandra]

@iangilman yes, you are right. It could be another alternative solution for my problem. @avandecreme that sounds good, it is new for me about viewportToImageZoom. @iangilman also mention about that function previously, but still not sure yet how i will manage it for my problem. Will make some experiment about that later.

Thanks a lot for both of you.