[bug] mouse jitter

[willbr]

Apparently, this was introduced in Win10

https://www.3dmm.com/showthread.php?t=52743

Bobby Swisha

Ok so when I grab/move objects in 3DMM, it occasionally "jumps" and the object is like a foot away from where I grabbed it. This is really annoying when I'm only trying to move things a millimetre.

Jayrod

There have been some grievances about the jumping mouse cursor issue but I think I finally figured out what causes it.

3dmm snaps the cursor to the center when you move it outside the window, which is a common technique for tracking the mouse cursor and prevents the cursor from hitting the bounds of the screen or whatever. However, Windows 10 is so "responsive" that when 3dmm goes to grab the next mouse position, it sometimes doesn't get the newly "snapped" position it set before, and so there are incremental issues while dragging. Like in this video:

The fix I came up with was to add some milliseconds of idle time after each call to the Windows API SetCursorPos function (in User32.dll) to give time for Windows to dispatch the events.

Download it here.

-To use it, you must have 3dmm/v3dmm already running. Then just run it and it should patch successfully. The caveat atm is you must run the utility again if you close the 3dmm window. (I don't know yet how to make the patch effective on harddisk as the offsets to the DLLs will vary each time you start up 3dmm.)

https://3dmm.com/showthread.php?p=1246421

https://www.youtube.com/watch?v=zkHAGQlpcp8

similar problems reported on the SDL mailing list

libsdl-org/SDL#2695
https://discourse.libsdl.org/t/win10-fall-creators-update-breaks-mouse-warping/23526

[willbr]

I've tried adding a delay to AdjustCursor, but that hasn't sovled the problem for me.

3DMMForever/src/engine/movie.cpp

Lines 6256 to 6290 in 79b3010

	/***************************************************************************
	*
	* Call this function when you have the cursor hidden and you want to
	* "reset" its position after using the mouse position to adjust an actor.
	* It updates _xpPrev and _ypPrev. Then, if the cursor has gone outside
	* the gob, it warps the cursor to the center of the gob. This way, the
	* actor doesn't seem to hit an invisible "wall" just because the (hidden)
	* cursor has hit the edge of the screen.
	*
	* Parameters:
	* (xp, yp): current cursor position
	*
	* Returns:
	* None.
	*
	**************************************************************************/
	void MVU::AdjustCursor(long xp, long yp)
	{
	AssertThis(0);
	RC rc;
	GetRc(&rc, cooLocal);
	rc.Inset(kdpInset, kdpInset); // warp before the cursor gets close to the gob's edge
	if (rc.FPtIn(xp, yp))
	{
	_xpPrev = xp;
	_ypPrev = yp;
	_dzrPrev = rZero;
	}
	else
	{
	WarpCursToCenter();
	}
	}

[willbr]

I've had more luck making it wrap more frequently, by increasing the inset size to 200.

3DMMForever/src/engine/movie.cpp

Lines 45 to 48 in 79b3010

	//
	// How many pixels from edge to warp cursor back to center
	//
	const long kdpInset = 50;

[frank-weindel]

@willbr Are you running 3DMM in a Windows VM by any chance? Because I do recall having a very bad mouse jumping issue with that. It had to do with a mode in the VM software (Parallels in my case) that simulates the mouse cursor natively. When enabled, it's unable to respond to events from the 3DMM/Windows to update the position of the simulated mouse cursor on the host OS.

[willbr]

I'm not. Just native Windows 11.

Edition	Windows 11 Home
Version	22H2
Installed on	‎2023-‎01-‎28
OS build	22621.2134
Experience	Windows Feature Experience Pack 1000.22659.1000.0