Tell Windows that we're HighDPI aware.

This prevents Windows from scaling our (fullscreen) window to crap if
the whole desktop is scaled and we're rendering more than 1080p. This is
believed to fix #208.

src/backends/windows/system.c

@@ -688,6 +688,50 @@ Sys_RedirectStdout(void)
 
 /* ======================================================================= */
 
+typedef enum YQ2_PROCESS_DPI_AWARENESS {
+	YQ2_PROCESS_DPI_UNAWARE = 0,
+	YQ2_PROCESS_SYSTEM_DPI_AWARE = 1,
+	YQ2_PROCESS_PER_MONITOR_DPI_AWARE = 2
+} YQ2_PROCESS_DPI_AWARENESS;
+
+void
+Sys_SetHighDPIMode(void)
+{
+	/* For Vista, Win7 and Win8 */
+	BOOL(WINAPI *SetProcessDPIAware)(void) = NULL;
+
+	/* Win8.1 and later */
+	HRESULT(WINAPI *SetProcessDpiAwareness)(YQ2_PROCESS_DPI_AWARENESS dpiAwareness) = NULL;
+
+
+	HINSTANCE userDLL = LoadLibrary("USER32.DLL");
+
+	if (userDLL)
+	{
+		SetProcessDPIAware = (BOOL(WINAPI *)(void)) GetProcAddress(userDLL,
+				"SetProcessDPIAware");
+	}
+
+
+	HINSTANCE shcoreDLL = LoadLibrary("SHCORE.DLL");
+
+	if (shcoreDLL)
+	{
+		SetProcessDpiAwareness = (HRESULT(WINAPI *)(YQ2_PROCESS_DPI_AWARENESS))
+			GetProcAddress(shcoreDLL, "SetProcessDpiAwareness");
+	}
+
+
+	if (SetProcessDpiAwareness) {
+		SetProcessDpiAwareness(YQ2_PROCESS_PER_MONITOR_DPI_AWARE);
+	}
+	else if (SetProcessDPIAware) {
+		SetProcessDPIAware();
+	}
+}
+
+/* ======================================================================= */
+
 /*
  * Windows main function. Containts the
  * initialization code and the main loop
@@ -708,6 +752,10 @@ WinMain(HINSTANCE hInstance, HINSTANCE hPrevInstance,
 	/* Make the current instance global */
 	global_hInstance = hInstance;
 
+	/* Force DPI awareness */
+	Sys_SetHighDPIMode();
+
+	/* FIXME: No one can see this! */
 	printf("Yamagi Quake II v%s\n", YQ2VERSION);
 	printf("=====================\n\n");