Windows: Start at a sensible window size if high-DPI. Avoids the worst of #9437 but does not fix it.

Core/Core.cpp

@@ -130,21 +130,6 @@ bool Core_GetPowerSaving() {
 	return powerSaving;
 }
 
-#ifdef _WIN32
-#if PPSSPP_PLATFORM(UWP)
-static int ScreenDPI() {
-	return 96;  // TODO UWP
-}
-#else
-static int ScreenDPI() {
-	HDC screenDC = GetDC(nullptr);
-	int dotsPerInch = GetDeviceCaps(screenDC, LOGPIXELSY);
-	ReleaseDC(nullptr, screenDC);
-	return dotsPerInch;
-}
-#endif
-#endif
-
 static bool IsWindowSmall(int pixelWidth, int pixelHeight) {
 	// Can't take this from config as it will not be set if windows is maximized.
 	int w = (int)(pixelWidth * g_dpi_scale);
@@ -156,10 +141,7 @@ static bool IsWindowSmall(int pixelWidth, int pixelHeight) {
 bool UpdateScreenScale(int width, int height) {
 	bool smallWindow;
 #ifdef _WIN32
-	// Use legacy DPI handling, because we still compile as XP compatible we don't get the new SDK, unless
+	g_dpi = System_GetPropertyInt(SYSPROP_DISPLAY_DPI);
-	// we do unholy tricks.
-
-	g_dpi = ScreenDPI();
 	g_dpi_scale = 96.0f / g_dpi;
 #else
 	g_dpi = 96;

Windows/MainWindow.cpp

@@ -394,7 +394,12 @@ namespace MainWindow
 		if (g_Config.iWindowWidth <= 0 || g_Config.iWindowHeight <= 0) {
 			RECT rcInner = rc, rcOuter;
 			bool portrait = g_Config.IsPortrait();
-			GetWindowRectAtResolution(2 * (portrait ? 272 : 480), 2 * (portrait ? 480 : 272), rcInner, rcOuter);
+
+			// We want to adjust for DPI but still get an integer pixel scaling ratio.
+			double dpi_scale = 96.0 / System_GetPropertyInt(SYSPROP_DISPLAY_DPI);
+			int scale = (int)ceil(2.0 / dpi_scale);
+
+			GetWindowRectAtResolution(scale * (portrait ? 272 : 480), scale * (portrait ? 480 : 272), rcInner, rcOuter);
 			rc.right = rc.left + (rcOuter.right - rcOuter.left);
 			rc.bottom = rc.top + (rcOuter.bottom - rcOuter.top);
 			g_Config.iWindowWidth = rc.right - rc.left;

Windows/main.cpp

@@ -187,6 +187,21 @@ std::string System_GetProperty(SystemProperty prop) {
 // Ugly!
 extern WindowsAudioBackend *winAudioBackend;
 
+#ifdef _WIN32
+#if PPSSPP_PLATFORM(UWP)
+static int ScreenDPI() {
+	return 96;  // TODO UWP
+}
+#else
+static int ScreenDPI() {
+	HDC screenDC = GetDC(nullptr);
+	int dotsPerInch = GetDeviceCaps(screenDC, LOGPIXELSY);
+	ReleaseDC(nullptr, screenDC);
+	return dotsPerInch;
+}
+#endif
+#endif
+
 int System_GetPropertyInt(SystemProperty prop) {
 	switch (prop) {
 	case SYSPROP_AUDIO_SAMPLE_RATE:
@@ -195,6 +210,8 @@ int System_GetPropertyInt(SystemProperty prop) {
 		return 60000;
 	case SYSPROP_DEVICE_TYPE:
 		return DEVICE_TYPE_DESKTOP;
+	case SYSPROP_DISPLAY_DPI:
+		return ScreenDPI();
 	default:
 		return -1;
 	}

ext/native/base/NativeApp.h

@@ -157,6 +157,7 @@ enum SystemProperty {
 	SYSPROP_DISPLAY_XRES,
 	SYSPROP_DISPLAY_YRES,
 	SYSPROP_DISPLAY_REFRESH_RATE,  // returns 1000*the refresh rate in Hz as it can be non-integer
+	SYSPROP_DISPLAY_DPI,
 	SYSPROP_MOGA_VERSION,
 
 	SYSPROP_DEVICE_TYPE,