gtk2/gdk/win32/gdkdevice-win32.c
Luca Bacci aec87a3514
GdkWin32: Fix mouse events in presence of transparent windows on the desktop
In gdkdevice-win32.c we are interested in knowing which window
receives mouse input at a specific location.

Only WindowFromPoint is the right API for the task, other API's
(such as (Real)ChildWindowFromPoint(Ex)) have shortcomings because
they are really designed for other purposes. For example, only
WindowFromPoint is able to look through transparent layered windows.

So even if we want to find a direct child we have to use
WindowFromPoint and then walk up the hierarchy.

Fixes: #370, #417
See: !2800
2020-11-11 12:46:52 +01:00

231 lines
6.1 KiB
C

/* GDK - The GIMP Drawing Kit
* Copyright (C) 2009 Carlos Garnacho <carlosg@gnome.org>
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2 of the License, or (at your option) any later version.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library. If not, see <http://www.gnu.org/licenses/>.
*/
#include "config.h"
#include <gdk/gdksurface.h>
#include <windowsx.h>
#include <objbase.h>
#include <math.h>
#include "gdkdevice-win32.h"
#include "gdkwin32.h"
#include "gdkdisplay-win32.h"
#include "gdkdevice-virtual.h"
#include "gdkdevice-wintab.h"
G_DEFINE_TYPE (GdkDeviceWin32, gdk_device_win32, GDK_TYPE_DEVICE)
static void
gdk_device_win32_set_surface_cursor (GdkDevice *device,
GdkSurface *window,
GdkCursor *cursor)
{
}
static GdkModifierType
get_current_mask (void)
{
GdkModifierType mask;
BYTE kbd[256];
GetKeyboardState (kbd);
mask = 0;
if (kbd[VK_SHIFT] & 0x80)
mask |= GDK_SHIFT_MASK;
if (kbd[VK_CAPITAL] & 0x80)
mask |= GDK_LOCK_MASK;
if (kbd[VK_CONTROL] & 0x80)
mask |= GDK_CONTROL_MASK;
if (kbd[VK_MENU] & 0x80)
mask |= GDK_ALT_MASK;
if (kbd[VK_LBUTTON] & 0x80)
mask |= GDK_BUTTON1_MASK;
if (kbd[VK_MBUTTON] & 0x80)
mask |= GDK_BUTTON2_MASK;
if (kbd[VK_RBUTTON] & 0x80)
mask |= GDK_BUTTON3_MASK;
return mask;
}
static void
gdk_device_win32_query_state (GdkDevice *device,
GdkSurface *window,
GdkSurface **child_window,
double *win_x,
double *win_y,
GdkModifierType *mask)
{
POINT point;
HWND hwnd, hwndc;
int scale;
if (window)
{
scale = GDK_WIN32_SURFACE (window)->surface_scale;
hwnd = GDK_SURFACE_HWND (window);
}
else
{
GdkDisplay *display = gdk_device_get_display (device);
scale = GDK_WIN32_DISPLAY (display)->surface_scale;
hwnd = NULL;
}
GetCursorPos (&point);
if (hwnd)
ScreenToClient (hwnd, &point);
if (win_x)
*win_x = point.x / scale;
if (win_y)
*win_y = point.y / scale;
if (window)
{
if (win_x)
*win_x += _gdk_offset_x;
if (win_y)
*win_y += _gdk_offset_y;
}
if (hwnd && child_window)
{
hwndc = ChildWindowFromPoint (hwnd, point);
if (hwndc && hwndc != hwnd)
*child_window = gdk_win32_handle_table_lookup (hwndc);
else
*child_window = NULL; /* Direct child unknown to gdk */
}
if (mask)
*mask = get_current_mask ();
}
void
_gdk_device_win32_query_state (GdkDevice *device,
GdkSurface *window,
GdkSurface **child_window,
double *win_x,
double *win_y,
GdkModifierType *mask)
{
if (GDK_IS_DEVICE_VIRTUAL (device))
gdk_device_virtual_query_state (device, window, child_window, win_x, win_y, mask);
else if (GDK_IS_DEVICE_WINTAB (device))
gdk_device_wintab_query_state (device, window, child_window, win_x, win_y, mask);
else
gdk_device_win32_query_state (device, window, child_window, win_x, win_y, mask);
}
static GdkGrabStatus
gdk_device_win32_grab (GdkDevice *device,
GdkSurface *window,
gboolean owner_events,
GdkEventMask event_mask,
GdkSurface *confine_to,
GdkCursor *cursor,
guint32 time_)
{
/* No support for grabbing physical devices atm */
return GDK_GRAB_NOT_VIEWABLE;
}
static void
gdk_device_win32_ungrab (GdkDevice *device,
guint32 time_)
{
}
static void
screen_to_client (HWND hwnd, POINT screen_pt, POINT *client_pt)
{
*client_pt = screen_pt;
ScreenToClient (hwnd, client_pt);
}
GdkSurface *
_gdk_device_win32_surface_at_position (GdkDevice *device,
double *win_x,
double *win_y,
GdkModifierType *mask)
{
GdkSurface *window = NULL;
GdkWin32Surface *impl = NULL;
POINT screen_pt, client_pt;
HWND hwnd;
RECT rect;
if (!GetCursorPos (&screen_pt))
return NULL;
/* Use WindowFromPoint instead of ChildWindowFromPoint(Ex).
* Only WindowFromPoint is able to look through transparent
* layered windows.
*/
hwnd = GetAncestor (WindowFromPoint (screen_pt), GA_ROOT);
/* Verify that we're really inside the client area of the window */
GetClientRect (hwnd, &rect);
screen_to_client (hwnd, screen_pt, &client_pt);
if (!PtInRect (&rect, client_pt))
hwnd = NULL;
window = gdk_win32_handle_table_lookup (hwnd);
if (window && (win_x || win_y))
{
impl = GDK_WIN32_SURFACE (window);
if (win_x)
*win_x = client_pt.x / impl->surface_scale;
if (win_y)
*win_y = client_pt.y / impl->surface_scale;
}
return window;
}
static void
gdk_device_win32_class_init (GdkDeviceWin32Class *klass)
{
GdkDeviceClass *device_class = GDK_DEVICE_CLASS (klass);
device_class->set_surface_cursor = gdk_device_win32_set_surface_cursor;
device_class->grab = gdk_device_win32_grab;
device_class->ungrab = gdk_device_win32_ungrab;
device_class->surface_at_position = _gdk_device_win32_surface_at_position;
}
static void
gdk_device_win32_init (GdkDeviceWin32 *device_win32)
{
GdkDevice *device;
device = GDK_DEVICE (device_win32);
_gdk_device_add_axis (device, GDK_AXIS_X, 0, 0, 1);
_gdk_device_add_axis (device, GDK_AXIS_Y, 0, 0, 1);
}