I'm curious about why the Image Viewer in dopus is so laggy when zooming in and out of images. This is a demonstration video comparing the performance of dopus's built-in Image Viewer, XnView, and the default Windows Photo on the same image. To make the difference more obvious, I used the mouse wheel to scroll continuously for several rounds in a short period of time, quickly zooming the image to its maximum or minimum size.
As you can see, both XnView and Windows Photo perform smoothly without any noticeable loading delays. However, the dopus image viewer clearly lags, requiring a wait of one or two seconds, during which the mouse pointer starts spinning.
Why is this the case? I don't think it's a problem with my computer's performance. I've tested this on several computers with different hardwares, and the dopus viewer consistently loads more slowly than the other software. Moreover, a 20MB image is not particularly large and should not cause such lag.