From 63203fb881bfce667a14b2bbb3ec2ee40a9adf77 Mon Sep 17 00:00:00 2001
From: Thomas Holder <thomas@thomas-holder.de>
Date: Sat, 27 Jul 2019 14:40:29 +0000
Subject: Make doc2dt a document property

Closes #340
---
 src/document.h | 16 ++++++++++++++++
 1 file changed, 16 insertions(+)

(limited to 'src/document.h')

diff --git a/src/document.h b/src/document.h
index 609d665bc..fd7e15fc5 100644
--- a/src/document.h
+++ b/src/document.h
@@ -29,6 +29,7 @@
 #include <glibmm/ustring.h>
 #include <sigc++/sigc++.h>
 
+#include <2geom/affine.h>
 #include <2geom/forward.h>
 
 #include "3rdparty/libcroco/cr-cascade.h"
@@ -390,7 +391,22 @@ private:
 
     sigc::signal<void> destroySignal;
 
+    mutable Geom::Affine _doc2dt;
+
 public:
+    /// Document to desktop coordinate transformation.
+    const Geom::Affine &doc2dt() const;
+    /// Desktop to document coordinate transformation.
+    const Geom::Affine &dt2doc() const
+    {
+        // Note: doc2dt().inverse() happens to be identical to doc2dt()
+        return doc2dt();
+    }
+    /// True if the desktop Y-axis points down, false if it points up.
+    bool is_yaxisdown() const { return yaxisdir() > 0; }
+    /// "1" if the desktop Y-axis points down, "-1" if it points up.
+    double yaxisdir() const { return _doc2dt[3]; }
+
     void addUndoObserver(Inkscape::UndoStackObserver& observer);
     void removeUndoObserver(Inkscape::UndoStackObserver& observer);
 
-- 
cgit v1.2.3