From b44e7470de1d90632641f6e4308a88316668215b Mon Sep 17 00:00:00 2001
From: Sam Lantinga <slouken@libsdl.org>
Date: Mon, 30 Dec 2013 12:49:15 -0800
Subject: [PATCH] Fixed display mode calculations for applications which are
 not DPI aware. If your application wants to have access to the full
 resolution even when the system has DPI scaling enabled, call
 SetProcessDPIAware() before calling SDL_Init()

e.g.
	typedef BOOL (WINAPI *SetProcessDPIAware_t)(void);
	HMODULE hMod = LoadLibrary("user32.dll");
	if ( hMod ) {
		SetProcessDPIAware_t pSetProcessDPIAware = GetProcAddress( hMod, "SetProcessDPIAware" );
		if ( pSetProcessDPIAware ) {
			pSetProcessDPIAware();
		}
		FreeLibrary( hMod );
	}
---
 src/video/windows/SDL_windowsmodes.c | 22 +++++++++++++++-------
 src/video/windows/SDL_windowsmodes.h |  2 ++
 2 files changed, 17 insertions(+), 7 deletions(-)

diff --git a/src/video/windows/SDL_windowsmodes.c b/src/video/windows/SDL_windowsmodes.c
index 73cae8f37..f583b0baa 100644
--- a/src/video/windows/SDL_windowsmodes.c
+++ b/src/video/windows/SDL_windowsmodes.c
@@ -50,6 +50,8 @@ WIN_GetDisplayMode(LPCTSTR deviceName, DWORD index, SDL_DisplayMode * mode)
     data->DeviceMode.dmFields =
         (DM_BITSPERPEL | DM_PELSWIDTH | DM_PELSHEIGHT | DM_DISPLAYFREQUENCY |
          DM_DISPLAYFLAGS);
+	data->ScaleX = 1.0f;
+	data->ScaleY = 1.0f;
 
     /* Fill in the mode information */
     mode->format = SDL_PIXELFORMAT_UNKNOWN;
@@ -63,6 +65,13 @@ WIN_GetDisplayMode(LPCTSTR deviceName, DWORD index, SDL_DisplayMode * mode)
         char bmi_data[sizeof(BITMAPINFOHEADER) + 256 * sizeof(RGBQUAD)];
         LPBITMAPINFO bmi;
         HBITMAP hbm;
+		int logical_width = GetDeviceCaps( hdc, HORZRES );
+		int logical_height = GetDeviceCaps( hdc, VERTRES );
+
+		data->ScaleX = (float)logical_width / devmode.dmPelsWidth;
+		data->ScaleY = (float)logical_height / devmode.dmPelsHeight;
+		mode->w = logical_width;
+		mode->h = logical_height;
 
         SDL_zero(bmi_data);
         bmi = (LPBITMAPINFO) bmi_data;
@@ -93,7 +102,7 @@ WIN_GetDisplayMode(LPCTSTR deviceName, DWORD index, SDL_DisplayMode * mode)
         } else if (bmi->bmiHeader.biBitCount == 4) {
             mode->format = SDL_PIXELFORMAT_INDEX4LSB;
         }
-    } else {
+	} else {
         /* FIXME: Can we tell what this will be? */
         if ((devmode.dmFields & DM_BITSPERPEL) == DM_BITSPERPEL) {
             switch (devmode.dmBitsPerPel) {
@@ -224,10 +233,10 @@ WIN_GetDisplayBounds(_THIS, SDL_VideoDisplay * display, SDL_Rect * rect)
 {
     SDL_DisplayModeData *data = (SDL_DisplayModeData *) display->current_mode.driverdata;
 
-    rect->x = (int)data->DeviceMode.dmPosition.x;
-    rect->y = (int)data->DeviceMode.dmPosition.y;
-    rect->w = data->DeviceMode.dmPelsWidth;
-    rect->h = data->DeviceMode.dmPelsHeight;
+    rect->x = (int)SDL_ceil(data->DeviceMode.dmPosition.x * data->ScaleX);
+    rect->y = (int)SDL_ceil(data->DeviceMode.dmPosition.y * data->ScaleY);
+    rect->w = (int)SDL_ceil(data->DeviceMode.dmPelsWidth * data->ScaleX);
+    rect->h = (int)SDL_ceil(data->DeviceMode.dmPelsHeight * data->ScaleY);
 
     return 0;
 }
@@ -252,8 +261,7 @@ WIN_GetDisplayModes(_THIS, SDL_VideoDisplay * display)
             if (!SDL_AddDisplayMode(display, &mode)) {
                 SDL_free(mode.driverdata);
             }
-        }
-        else {
+        } else {
             SDL_free(mode.driverdata);
         }
     }
diff --git a/src/video/windows/SDL_windowsmodes.h b/src/video/windows/SDL_windowsmodes.h
index fd622d56c..c13670b1c 100644
--- a/src/video/windows/SDL_windowsmodes.h
+++ b/src/video/windows/SDL_windowsmodes.h
@@ -31,6 +31,8 @@ typedef struct
 typedef struct
 {
     DEVMODE DeviceMode;
+	float ScaleX;
+	float ScaleY;
 } SDL_DisplayModeData;
 
 extern int WIN_InitModes(_THIS);