get display DPI info to scale mouse movement

host/platform/Windows/capture/DXGI/src/dxgi.c

@@ -24,6 +24,7 @@ Place, Suite 330, Boston, MA 02111-1307 USA
 #include "common/option.h"
 #include "common/locking.h"
 #include "common/event.h"
+#include "common/dpi.h"
 
 #include <assert.h>
 #include <stdatomic.h>
@@ -98,12 +99,12 @@ struct iface
   unsigned int  pitch;
   unsigned int  stride;
   CaptureFormat format;
+  unsigned int  dpi;
 
   int  lastPointerX, lastPointerY;
   bool lastPointerVisible;
 };
 
-static bool           dpiDone = false;
 static struct iface * this    = NULL;
 
 // forwards
@@ -210,22 +211,6 @@ static bool dxgi_init()
     DEBUG_INFO("looking-glass-host.exe InstallService");
   }
 
-  // this is required for DXGI 1.5 support to function
-  if (!dpiDone)
-  {
-    DECLARE_HANDLE(DPI_AWARENESS_CONTEXT);
-    #define DPI_AWARENESS_CONTEXT_PER_MONITOR_AWARE_V2  ((DPI_AWARENESS_CONTEXT)-4)
-    typedef BOOL (*User32_SetProcessDpiAwarenessContext)(DPI_AWARENESS_CONTEXT value);
-
-    HMODULE user32 = LoadLibraryA("user32.dll");
-    User32_SetProcessDpiAwarenessContext fn;
-    fn = (User32_SetProcessDpiAwarenessContext)GetProcAddress(user32, "SetProcessDpiAwarenessContext");
-    if (fn)
-      fn(DPI_AWARENESS_CONTEXT_PER_MONITOR_AWARE_V2);
-    FreeLibrary(user32);
-    dpiDone = true;
-  }
-
   HRESULT          status;
   DXGI_OUTPUT_DESC outputDesc;
 
@@ -388,6 +373,7 @@ static bool dxgi_init()
   IDXGIAdapter1_GetDesc1(this->adapter, &adapterDesc);
   this->width  = outputDesc.DesktopCoordinates.right  - outputDesc.DesktopCoordinates.left;
   this->height = outputDesc.DesktopCoordinates.bottom - outputDesc.DesktopCoordinates.top;
+  this->dpi    = monitor_dpi(outputDesc.Monitor);
   ++this->formatVer;
 
   DEBUG_INFO("Device Descripion: %ls"    , adapterDesc.Description);
@@ -688,6 +674,14 @@ static unsigned int dxgi_getMaxFrameSize()
   return this->height * this->pitch;
 }
 
+static unsigned int dxgi_getMouseScale()
+{
+  assert(this);
+  assert(this->initialized);
+
+  return this->dpi * 100 / DPI_100_PERCENT;
+}
+
 static CaptureResult dxgi_hResultToCaptureResult(const HRESULT status)
 {
   switch(status)
@@ -1013,6 +1007,7 @@ struct CaptureInterface Capture_DXGI =
   .deinit          = dxgi_deinit,
   .free            = dxgi_free,
   .getMaxFrameSize = dxgi_getMaxFrameSize,
+  .getMouseScale   = dxgi_getMouseScale,
   .capture         = dxgi_capture,
   .waitFrame       = dxgi_waitFrame,
   .getFrame        = dxgi_getFrame

host/platform/Windows/capture/NVFBC/src/nvfbc.c

@@ -25,6 +25,7 @@ Place, Suite 330, Boston, MA 02111-1307 USA
 #include "common/framebuffer.h"
 #include "common/event.h"
 #include "common/thread.h"
+#include "common/dpi.h"
 #include <assert.h>
 #include <stdlib.h>
 #include <windows.h>
@@ -44,6 +45,7 @@ struct iface
 
   unsigned int maxWidth , maxHeight;
   unsigned int width    , height;
+  unsigned int dpi;
 
   unsigned int formatVer;
   unsigned int grabWidth, grabHeight, grabStride;
@@ -65,7 +67,7 @@ static struct iface * this = NULL;
 static void nvfbc_free();
 static int pointerThread(void * unused);
 
-static void getDesktopSize(unsigned int * width, unsigned int * height)
+static void getDesktopSize(unsigned int * width, unsigned int * height, unsigned int * dpi)
 {
   HMONITOR    monitor     = MonitorFromWindow(GetDesktopWindow(), MONITOR_DEFAULTTOPRIMARY);
   MONITORINFO monitorInfo = {
@@ -73,6 +75,7 @@ static void getDesktopSize(unsigned int * width, unsigned int * height)
   };
 
   GetMonitorInfo(monitor, &monitorInfo);
+  *dpi = monitor_dpi(monitor);
   CloseHandle(monitor);
 
   *width  = monitorInfo.rcMonitor.right  - monitorInfo.rcMonitor.left;
@@ -163,7 +166,7 @@ static bool nvfbc_create(
 static bool nvfbc_init()
 {
   this->stop = false;
-  getDesktopSize(&this->width, &this->height);
+  getDesktopSize(&this->width, &this->height, &this->dpi);
   lgResetEvent(this->frameEvent);
 
   HANDLE event;
@@ -245,9 +248,14 @@ static unsigned int nvfbc_getMaxFrameSize()
   return this->maxWidth * this->maxHeight * 4;
 }
 
+static unsigned int nvfbc_getMouseScale()
+{
+  return this->dpi * 100 / DPI_100_PERCENT;
+}
+
 static CaptureResult nvfbc_capture()
 {
-  getDesktopSize(&this->width, &this->height);
+  getDesktopSize(&this->width, &this->height, &this->dpi);
   NvFBCFrameGrabInfo grabInfo;
   CaptureResult result = NvFBCToSysCapture(
     this->nvfbc,
@@ -397,6 +405,7 @@ struct CaptureInterface Capture_NVFBC =
   .deinit          = nvfbc_deinit,
   .free            = nvfbc_free,
   .getMaxFrameSize = nvfbc_getMaxFrameSize,
+  .getMouseScale   = nvfbc_getMouseScale,
   .capture         = nvfbc_capture,
   .waitFrame       = nvfbc_waitFrame,
   .getFrame        = nvfbc_getFrame

host/platform/Windows/src/platform.c

@@ -226,6 +226,18 @@ int WINAPI WinMain(HINSTANCE hInstance, HINSTANCE hPrevInstance, LPSTR lpCmdLine
   // setup a handler for ctrl+c
   SetConsoleCtrlHandler(CtrlHandler, TRUE);
 
+  // enable high DPI awareness
+  // this is required for DXGI 1.5 support to function and also capturing desktops with high DPI
+  DECLARE_HANDLE(DPI_AWARENESS_CONTEXT);
+  #define DPI_AWARENESS_CONTEXT_PER_MONITOR_AWARE_V2  ((DPI_AWARENESS_CONTEXT)-4)
+  typedef BOOL (*User32_SetProcessDpiAwarenessContext)(DPI_AWARENESS_CONTEXT value);
+
+  HMODULE user32 = GetModuleHandle("user32.dll");
+  User32_SetProcessDpiAwarenessContext fn;
+  fn = (User32_SetProcessDpiAwarenessContext)GetProcAddress(user32, "SetProcessDpiAwarenessContext");
+  if (fn)
+    fn(DPI_AWARENESS_CONTEXT_PER_MONITOR_AWARE_V2);
+
   // create a message window so that our message pump works
   WNDCLASSEX wx    = {};
   wx.cbSize        = sizeof(WNDCLASSEX);
@@ -249,7 +261,6 @@ int WINAPI WinMain(HINSTANCE hInstance, HINSTANCE hPrevInstance, LPSTR lpCmdLine
   app.messageWnd = CreateWindowEx(0, MAKEINTATOM(class), NULL, 0, 0, 0, 0, 0, NULL, NULL, hInstance, NULL);
 
   // this is needed so that unprivileged processes can send us this message
-  HMODULE user32 = GetModuleHandle("user32.dll");
   _ChangeWindowMessageFilterEx = (PChangeWindowMessageFilterEx)GetProcAddress(user32, "ChangeWindowMessageFilterEx");
   if (_ChangeWindowMessageFilterEx)
     _ChangeWindowMessageFilterEx(app.messageWnd, app.trayRestartMsg, MSGFLT_ALLOW, NULL);