From baeadebbc4e68e19c445d8808e363e0c894163b4 Mon Sep 17 00:00:00 2001
From: "Adam D. Ruppe" <destructionator@gmail.com>
Date: Tue, 8 Jan 2019 11:03:53 -0500
Subject: [PATCH] add dpi function

---
 simpledisplay.d | 23 +++++++++++++++++++++++
 1 file changed, 23 insertions(+)

diff --git a/simpledisplay.d b/simpledisplay.d
index 001abdb..0e26bce 100644
--- a/simpledisplay.d
+++ b/simpledisplay.d
@@ -1158,6 +1158,27 @@ string sdpyWindowClass () {
 	return null;
 }
 
+/++
+	Returns the DPI of the default monitor. [0] is width, [1] is height (they are usually the same though). You may wish to round the numbers off.
++/
+float[2] getDpi() {
+	float[2] dpi;
+	version(Windows) {
+		HDC screen = GetDC(null);
+		dpi[0] = GetDeviceCaps(screen, LOGPIXELSX);
+		dpi[1] = GetDeviceCaps(screen, LOGPIXELSY);
+	} else version(X11) {
+		auto display = XDisplayConnection.get;
+		auto screen = DefaultScreen(display);
+
+		// 25.4 millimeters in an inch...
+		dpi[0] = cast(float) DisplayWidth(display, screen) / DisplayWidthMM(display, screen) * 25.4;
+		dpi[1] = cast(float) DisplayHeight(display, screen) / DisplayHeightMM(display, screen) * 25.4;
+	}
+
+	return dpi;
+}
+
 TrueColorImage trueColorImageFromNativeHandle(NativeWindowHandle handle, int width, int height) {
 	throw new Exception("not implemented");
 	version(none) {
@@ -11897,6 +11918,8 @@ struct Visual
 	int DefaultDepth(Display* dpy, int scr) { return ScreenOfDisplay(dpy, scr).root_depth; }
 	int DisplayWidth(Display* dpy, int scr) { return ScreenOfDisplay(dpy, scr).width; }
 	int DisplayHeight(Display* dpy, int scr) { return ScreenOfDisplay(dpy, scr).height; }
+	int DisplayWidthMM(Display* dpy, int scr) { return ScreenOfDisplay(dpy, scr).mwidth; }
+	int DisplayHeightMM(Display* dpy, int scr) { return ScreenOfDisplay(dpy, scr).mheight; }
 	auto DefaultColormap(Display* dpy, int scr) { return ScreenOfDisplay(dpy, scr).cmap; }
 
 	int ConnectionNumber(Display* dpy) { return dpy.fd; }