Mouse click drag threshold needed for better intuitivity

[tajinoxn]

Mouse click drag threshold is needed for a more intuitive click and click-drag interaction.

In the current XnView MP, a mouse down with 1 pixel or more movement is registered as a mouse drag, this makes triggering context menu from Viewer, Preview Panel or Fullscreen requiring precise right clicking with static 0 pixel mouse movement, which is pretty taxing when right clicking in the middle of a mouse move or right clicking with a Wacom tablet stylus' button while hovering millimeters over the tablet.

Try this :
1. With a default XnView config, open an image in Viewer or Fullscreen mode.
2. Try to bring out the right click contextual menu with the right mouse button while slightly moving the mouse
3. It would be hit and miss if the right click isn't executed while the mouse is perfectly static.

Suggestions :
I suggest to implement a 'Mouse drag threshold' setting in "Tools > Settings > Interface > Mouse" page. The value is in pixels.

A value of 0 pixel would behave like what it currently is.

A value of 3 pixels would make a mouse down with movement more than 3 pixels only to be registered as a mouse drag, 3 pixels or less and the mouse up is registered as a mouse click.

Should be implement globally for all mouse interaction within XnView MP.

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This mouse drag threshold setting is common in many applications, some are exposed to the user and some are not. It is implemented in Windows Explorer as well, try to click and drag a selection box or drag and move a file/folder and you will notice that mouse down with more than 4 pixels will only be registered as a mouse drag. The Windows Explorer drag threshold setting is in stored in registry HKEY_CURRENT_USER\Control Panel\Desktop\DragHeight and DragWidth.

Hope it make sense. Thanks.