0.84: Image "jumps" when selecting requires scrolling

[helmut]

XnView: MP 0.84
OS: Windows 10 - 64bit

When selecting an area of the image and then enhancing the selection towards the top of the image requiring scrolling, the image is suddenly repositioned and seems to "jump".

Effect: Irritating user interface.

To reproduce:
1. Open an medium image (e.g. 1.000 x 1.000 pixels)
2. Zoom into the image (e.g. 400%)
3. Move the image using the hand or the pan tool so that you can see the top right part of the image.
4. On the right side, start a selection and select towards the top so that the mouse cursor "touches" the toolbar and the image starts scrolling.
Actual behaviour (bug): When scrolling the image repositions horizontally all of a sudden and "jumps" to the right. Selection is completely off, now.

Expected behaviour: When scrolling, the image shouldn't reposition itself horizontally.

Note:
- The problem occurs whenever enhancing the selection beyond the images borders, regardless in which direction.
- The problem occurs both in View mode (Viewer) and in Fullscreen.

[vertigo]

Reproduced in windowed mode, but not fullscreen. For me, in fullscreen, it just stops at the edge of the screen.

[helmut]

Reproduced in windowed mode, but not fullscreen. For me, in fullscreen, it just stops at the edge of the screen.

Thank you for confirming, vertigo!

Reproduced

[xnview]

i can't reproduce, could you make a video?

[XnTriq]

i can't reproduce, could you make a video?

1. Start XnView MP with its default settings.
2. Maximize the window.
3. Activate Show scrollbars in Tools → Settings... → View → View.
4. Open an image in non-fullscreen view mode.
5. Use the + keyboard shortcut to zoom into the image until both the vertical and horizontal scrollbar show up.
6. Move the mouse cursor to the upper left corner of the visible part of the image (i.e. to the left edge of the screen and right below the main toolbar).
7. Press & hold the left mouse button to make a selection and move the cursor onto XnView's vertical scrollbar.
   The vertical scrollbar jumps to the top.
8. Close the image and repeat steps #4 through #6.
9. Press & hold the left mouse button to make a selection and move the cursor onto XnView's horizontal scrollbar.
   The horizontal scrollbar jumps to the left.

[xnview]

O.k., thank you, I can also reproduce the problem. Issue 1219 is fixed in next version.

[xnview]

This problem is supposed to be fixed in XnView MP 0.87. Please check and confirm the bug fix here.

[XnTriq]

This problem is supposed to be fixed in XnView MP 0.87. Please check and confirm the bug fix here.

Confirmed fixed