Support per-monitor DPI.

1 files changed, 18 insertions, 0 deletions

diff --git a/c/common.c b/c/common.c
index 804611d..a44462d 100644
--- a/c/common.c
+++ b/c/common.c
@@ -4,6 +4,24 @@
 #include "resource.h"
 #include "defs.h"
 
+/* Scale integer according to DPI. */
+int Dpi(int i)
+{
+	extern int IDPI;
+
+	if (IDPI == -1) {
+		HMODULE hModule;
+		FARPROC GetDpiForWindow;
+		extern HWND HWnd;
+		IDPI = 96;
+		hModule = LoadLibrary(TEXT("User32.dll"));
+		if (hModule && (GetDpiForWindow = GetProcAddress(hModule, "GetDpiForWindow")))
+			IDPI = GetDpiForWindow(HWnd);
+	}
+
+	return MulDiv(i, IDPI, 96);
+}
+
 /* Convert normal string to TSTR using given codepage. */
 TCHAR *
 TszFromSz(const char *sz, int iCp)