looking-glass/host/platform/Windows/src/force_compose.c
2023-10-20 15:36:34 +11:00

141 lines
3.6 KiB
C

/**
* Looking Glass
* Copyright © 2017-2023 The Looking Glass Authors
* https://looking-glass.io
*
* This program is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License as published by the Free
* Software Foundation; either version 2 of the License, or (at your option)
* any later version.
*
* This program 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 General Public License for
* more details.
*
* You should have received a copy of the GNU General Public License along
* with this program; if not, write to the Free Software Foundation, Inc., 59
* Temple Place, Suite 330, Boston, MA 02111-1307 USA
*/
#include "windows/force_compose.h"
#include "common/windebug.h"
#include <windows.h>
#include <stdbool.h>
struct ForceCompose
{
HANDLE event;
HANDLE thread;
};
static struct ForceCompose forceCompose = { 0 };
LRESULT CALLBACK windowProc(HWND hwnd, UINT message, WPARAM wParam, LPARAM lParam)
{
switch (message)
{
case WM_CLOSE:
return 0; // Don't allow close
case WM_DESTROY:
PostQuitMessage(0);
return 0;
case WM_PAINT:
{
PAINTSTRUCT ps;
HDC hdc = BeginPaint(hwnd, &ps);
FillRect(hdc, &ps.rcPaint, (HBRUSH) (COLOR_WINDOW+1));
EndPaint(hwnd, &ps);
return 0;
}
}
return DefWindowProc(hwnd, message, wParam, lParam);
}
static DWORD WINAPI threadProc(LPVOID lParam)
{
WNDCLASSA wc = { 0 };
wc.lpfnWndProc = windowProc;
wc.hInstance = (HINSTANCE) GetModuleHandle(NULL);
wc.lpszClassName = "looking-glass-force-composition";
RegisterClass(&wc);
HWND hwnd = CreateWindowEx(
WS_EX_TOOLWINDOW | WS_EX_TOPMOST | WS_EX_LAYERED, wc.lpszClassName,
"Looking Glass Helper Window", WS_POPUP, 0, 0, 1, 1, NULL, NULL,
wc.hInstance, NULL
);
if (!hwnd)
{
DEBUG_ERROR("Failed to create window to force composition");
goto exit;
}
SetLayeredWindowAttributes(hwnd, GetSysColor(COLOR_WINDOW), 0, LWA_COLORKEY);
ShowWindow(hwnd, SW_SHOW);
DEBUG_INFO("Created window to force composition");
MSG msg;
while (true)
{
switch (MsgWaitForMultipleObjects(1, &forceCompose.event, FALSE, INFINITE, QS_ALLINPUT))
{
case WAIT_OBJECT_0:
DEBUG_INFO("Force composition received quit request");
DestroyWindow(hwnd);
// Do not wait on the event after it has been signaled.
while (GetMessage(&msg, NULL, 0, 0) > 0)
{
TranslateMessage(&msg);
DispatchMessage(&msg);
}
goto exit;
case WAIT_OBJECT_0 + 1:
while (PeekMessage(&msg, NULL, 0, 0, PM_REMOVE))
{
if (msg.message == WM_QUIT)
goto exit;
TranslateMessage(&msg);
DispatchMessage(&msg);
}
break;
default:
DEBUG_WINERROR("MsgWaitForMultipleObjects failed", GetLastError());
goto exit;
}
}
exit:
UnregisterClass(wc.lpszClassName, wc.hInstance);
return 0;
}
void dwmForceComposition(void)
{
if (!forceCompose.event)
{
forceCompose.event = CreateEventA(NULL, FALSE, FALSE, NULL);
if (!forceCompose.event)
{
DEBUG_WINERROR("Failed to create unforce composition event", GetLastError());
return;
}
}
forceCompose.thread = CreateThread(NULL, 0, threadProc, NULL, 0, NULL);
}
void dwmUnforceComposition(void)
{
if (!forceCompose.event)
return;
SetEvent(forceCompose.event);
WaitForSingleObject(forceCompose.thread, INFINITE);
CloseHandle(forceCompose.thread);
forceCompose.thread = NULL;
}