RAWMOUSE structure

Contains information about the state of the mouse.

Syntax

typedef struct tagRAWMOUSE {
  USHORT usFlags;
  union {
    ULONG ulButtons;
    struct {
      USHORT usButtonFlags;
      USHORT usButtonData;
    } DUMMYSTRUCTNAME;
  } DUMMYUNIONNAME;
  ULONG  ulRawButtons;
  LONG   lLastX;
  LONG   lLastY;
  ULONG  ulExtraInformation;
} RAWMOUSE, *PRAWMOUSE, *LPRAWMOUSE;

Members

usFlags

Type: USHORT

The mouse state. This member can be any reasonable combination of the following.

Value Meaning
MOUSE_MOVE_RELATIVE
0
Mouse movement data is relative to the last mouse position. For further information about mouse motion, see the following Remarks section.
MOUSE_MOVE_ABSOLUTE
1
Mouse movement data is based on absolute position. For further information about mouse motion, see the following Remarks section.
MOUSE_VIRTUAL_DESKTOP
0x02
Mouse coordinates are mapped to the virtual desktop (for a multiple monitor system). For further information about mouse motion, see the following Remarks section.
MOUSE_ATTRIBUTES_CHANGED
0x04
Mouse attributes changed; application needs to query the mouse attributes.
MOUSE_MOVE_NOCOALESCE
0x08
This mouse movement event was not coalesced. Mouse movement events can be coalescened by default.
Windows XP/2000: This value is not supported.

DUMMYUNIONNAME

DUMMYUNIONNAME.ulButtons

Type: ULONG

Reserved.

DUMMYUNIONNAME.DUMMYSTRUCTNAME

DUMMYUNIONNAME.DUMMYSTRUCTNAME.usButtonFlags

Type: USHORT

The transition state of the mouse buttons. This member can be one or more of the following values.

Value Meaning
RI_MOUSE_LEFT_BUTTON_DOWN
0x0001
Left button changed to down.
RI_MOUSE_LEFT_BUTTON_UP
0x0002
Left button changed to up.
RI_MOUSE_MIDDLE_BUTTON_DOWN
0x0010
Middle button changed to down.
RI_MOUSE_MIDDLE_BUTTON_UP
0x0020
Middle button changed to up.
RI_MOUSE_RIGHT_BUTTON_DOWN
0x0004
Right button changed to down.
RI_MOUSE_RIGHT_BUTTON_UP
0x0008
Right button changed to up.
RI_MOUSE_BUTTON_1_DOWN
0x0001
RI_MOUSE_LEFT_BUTTON_DOWN
RI_MOUSE_BUTTON_1_UP
0x0002
RI_MOUSE_LEFT_BUTTON_UP
RI_MOUSE_BUTTON_2_DOWN
0x0004
RI_MOUSE_RIGHT_BUTTON_DOWN
RI_MOUSE_BUTTON_2_UP
0x0008
RI_MOUSE_RIGHT_BUTTON_UP
RI_MOUSE_BUTTON_3_DOWN
0x0010
RI_MOUSE_MIDDLE_BUTTON_DOWN
RI_MOUSE_BUTTON_3_UP
0x0020
RI_MOUSE_MIDDLE_BUTTON_UP
RI_MOUSE_BUTTON_4_DOWN
0x0040
XBUTTON1 changed to down.
RI_MOUSE_BUTTON_4_UP
0x0080
XBUTTON1 changed to up.
RI_MOUSE_BUTTON_5_DOWN
0x100
XBUTTON2 changed to down.
RI_MOUSE_BUTTON_5_UP
0x0200
XBUTTON2 changed to up.
RI_MOUSE_WHEEL
0x0400
Raw input comes from a mouse wheel. The wheel delta is stored in usButtonData.
A positive value indicates that the wheel was rotated forward, away from the user; a negative value indicates that the wheel was rotated backward, toward the user. For further information see the following Remarks section.
RI_MOUSE_HWHEEL
0x0800
Raw input comes from a horizontal mouse wheel. The wheel delta is stored in usButtonData.
A positive value indicates that the wheel was rotated to the right; a negative value indicates that the wheel was rotated to the left. For further information see the following Remarks section.
Windows XP/2000: This value is not supported.

DUMMYUNIONNAME.DUMMYSTRUCTNAME.usButtonData

Type: USHORT

If usButtonFlags has RI_MOUSE_WHEEL or RI_MOUSE_HWHEEL, this member specifies the distance the wheel is rotated. For further information see the following Remarks section.

ulRawButtons

Type: ULONG

The raw state of the mouse buttons. The Win32 subsystem does not use this member.

lLastX

Type: LONG

The motion in the X direction. This is signed relative motion or absolute motion, depending on the value of usFlags.

lLastY

Type: LONG

The motion in the Y direction. This is signed relative motion or absolute motion, depending on the value of usFlags.

ulExtraInformation

Type: ULONG

The device-specific additional information for the event.

Remarks

If the mouse has moved, indicated by MOUSE_MOVE_RELATIVE or MOUSE_MOVE_ABSOLUTE, lLastX and lLastY specify information about that movement. The information is specified as relative or absolute integer values.

If MOUSE_MOVE_RELATIVE value is specified, lLastX and lLastY specify movement relative to the previous mouse event (the last reported position). Positive values mean the mouse moved right (or down); negative values mean the mouse moved left (or up).

If MOUSE_MOVE_ABSOLUTE value is specified, lLastX and lLastY contain normalized absolute coordinates between 0 and 65,535. Coordinate (0,0) maps onto the upper-left corner of the display surface; coordinate (65535,65535) maps onto the lower-right corner. In a multimonitor system, the coordinates map to the primary monitor.

If MOUSE_VIRTUAL_DESKTOP is specified in addition to MOUSE_MOVE_ABSOLUTE, the coordinates map to the entire virtual desktop.

if ((rawMouse.usFlags & MOUSE_MOVE_ABSOLUTE) == MOUSE_MOVE_ABSOLUTE)
{
    bool isVirtualDesktop = (rawMouse.usFlags & MOUSE_VIRTUAL_DESKTOP) == MOUSE_VIRTUAL_DESKTOP;

    int width = GetSystemMetrics(isVirtualDesktop ? SM_CXVIRTUALSCREEN : SM_CXSCREEN);
    int height = GetSystemMetrics(isVirtualDesktop ? SM_CYVIRTUALSCREEN : SM_CYSCREEN);

    int absoluteX = int((rawMouse.lLastX / 65535.0f) * width);
    int absoluteY = int((rawMouse.lLastY / 65535.0f) * height);
}
else if (rawMouse.lLastX != 0 || rawMouse.lLastY != 0)
{
    int relativeX = rawMouse.lLastX;
    int relativeY = rawMouse.lLastY;
}

In contrast to legacy WM_MOUSEMOVE window messages Raw Input mouse events is not subject to the effects of the mouse speed set in the Control Panel's Mouse Properties sheet. See About Mouse Input for details.

If mouse wheel is moved, indicated by RI_MOUSE_WHEEL or RI_MOUSE_HWHEEL in usButtonFlags, then usButtonData contains a signed short value that specifies the distance the wheel is rotated.

The wheel rotation will be a multiple of WHEEL_DELTA, which is set at 120. This is the threshold for action to be taken, and one such action (for example, scrolling one increment) should occur for each delta.

The delta was set to 120 to allow Microsoft or other vendors to build finer-resolution wheels (a freely-rotating wheel with no notches) to send more messages per rotation, but with a smaller value in each message. To use this feature, you can either add the incoming delta values until WHEEL_DELTA is reached (so for a delta-rotation you get the same response), or scroll partial lines in response to the more frequent messages. You can also choose your scroll granularity and accumulate deltas until it is reached.

The application could also retrieve the current lines-to-scroll and characters-to-scroll user setting by using the SystemParametersInfo API with SPI_GETWHEELSCROLLLINES or SPI_GETWHEELSCROLLCHARS parameter.

Here is example of such wheel handling code:

if ((rawMouse.usButtonFlags & RI_MOUSE_WHEEL) == RI_MOUSE_WHEEL ||
    (rawMouse.usButtonFlags & RI_MOUSE_HWHEEL) == RI_MOUSE_HWHEEL)
{
    static const unsigned long defaultScrollLinesPerWheelDelta = 3;
    static const unsigned long defaultScrollCharsPerWheelDelta = 1;

    float wheelDelta = (float)(short)rawMouse.usButtonData;
    float numTicks = wheelDelta / WHEEL_DELTA;

    bool isHorizontalScroll = (rawMouse.usButtonFlags & RI_MOUSE_HWHEEL) == RI_MOUSE_HWHEEL;
    bool isScrollByPage = false;
    float scrollDelta = numTicks;

    if (isHorizontalScroll)
    {
        unsigned long scrollChars = defaultScrollCharsPerWheelDelta;
        SystemParametersInfo(SPI_GETWHEELSCROLLCHARS, 0, &scrollChars, 0);
        scrollDelta *= scrollChars;
    }
    else
    {
        unsigned long scrollLines = defaultScrollLinesPerWheelDelta;
        SystemParametersInfo(SPI_GETWHEELSCROLLLINES, 0, &scrollLines, 0);
        if (scrollLines == WHEEL_PAGESCROLL)
            isScrollByPage = true;
        else
            scrollDelta *= scrollLines;
    }
}

Requirements

   
Minimum supported client Windows XP [desktop apps only]
Minimum supported server Windows Server 2003 [desktop apps only]
Header winuser.h (include Windows.h)

See also

Conceptual

GetRawInputDeviceInfo

RAWINPUT

Raw Input

Reference

MOUSEINPUT structure

SendInput function

MOUSE_INPUT_DATA structure

About Mouse Input (legacy)

Mouse Input Notifications (legacy)

SystemParametersInfo