zoomTouchPinch problems after switching images

[leonardorame]

After trying for hours to make this work I post this here because maybe its a bug.

I have only one element to display images with the zoomTouchPinch tool attached. There are two images to be loaded there, one with cornerstoneWebImageLoader, the other with cornerstoneWADOImageLoader.

When I load the first image (it doesn't matter the order, it can be Web or WADO), it works as expected (expand fingers zoom in, contract fingers zoom out), then I switch (*) the image and zoomTouchPinch goes crazy allways zoomming out. It looks like this tool is not "reseted" properly before attaching to the new image.

*: The switching process follows these steps inside loadAndCacheImage:

// the next two lines refreshes the element. I don't know if there's a better way
cornerstone.disable(element);
cornerstone.enable(element);
cornerstone.displayImage(element, image);
cornerstoneTools.touchInput.enable(element);
cornerstoneTools.zoomTouchPinch.activate(element);

I've tried zoomTouchPinch.disable(element) before activate, but it doesn't fix the issue.

[swederik]

Hmm yeah definitely sounds like a bug. Strange because pinch input handling is quite simple.. I'll look into it. You shouldn't need to disable and re-enable the element just to switch images.

[leonardorame]

Hi Erik!, great to know this can be a bug, hopefully you can help me find a workaround/fix.

I know disabling/enabling the element shouldn't be needed, but before switching the images I have to hide the element's canvas with display:none, then, when set display:inline-block again the only way I found to display the element is disable/enable. Do you know a way to clear the canvas without display:none?.

[swederik]

What about using visibility or opacity in CSS instead of display?

[leonardorame]

Thanks that allowed me to remove disable/enable. I had to add cornerstone.resize(element, true) after displayImage because if not, the image was displayed very tiny,

BTW, this doesn't solve the zoomTouchPinch tool problem.

[swederik]

I can't seem to reproduce this bug. My code is here:

https://gist.github.com/swederik/8a416ad61dea2fcf9deb

Could you tell me if there anything you're doing that I'm not or vice versa?

[leonardorame]

Thanks to your example I found the problem, I was calling cornerstoneTools.touchInput.enable(element) inside loadAndCacheImage and you call it just after cornerstone.enable only once.

Fixed!.

[swederik]

Great! We actually had this same issue before for mouseInput (See #89), so now I've gone and made the same type of change for touch input so this type of bug doesn't occur anymore.

Thanks for the report.