1 files changed, 54 insertions, 0 deletions
diff --git a/slideshow/source/engine/transitions/doublediamondwipe.cxx b/slideshow/source/engine/transitions/doublediamondwipe.cxx
new file mode 100644
index 000000000..9c482000d
--- /dev/null
+++ b/slideshow/source/engine/transitions/doublediamondwipe.cxx
@@ -0,0 +1,54 @@
+/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
+/*
+ * This file is part of the LibreOffice project.
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/.
+ *
+ * This file incorporates work covered by the following license notice:
+ *
+ *   Licensed to the Apache Software Foundation (ASF) under one or more
+ *   contributor license agreements. See the NOTICE file distributed
+ *   with this work for additional information regarding copyright
+ *   ownership. The ASF licenses this file to you under the Apache
+ *   License, Version 2.0 (the "License"); you may not use this file
+ *   except in compliance with the License. You may obtain a copy of
+ *   the License at http://www.apache.org/licenses/LICENSE-2.0 .
+ */
+
+
+#include <basegfx/point/b2dpoint.hxx>
+#include "doublediamondwipe.hxx"
+
+
+namespace slideshow::internal {
+
+::basegfx::B2DPolyPolygon DoubleDiamondWipe::operator () ( double t )
+{
+    // outer:
+    const double a = ::basegfx::pruneScaleValue( 0.25 + (t * 0.75) );
+    ::basegfx::B2DPolygon poly;
+    poly.append( ::basegfx::B2DPoint( 0.5 + a, 0.5 ) );
+    poly.append( ::basegfx::B2DPoint( 0.5, 0.5 - a ) );
+    poly.append( ::basegfx::B2DPoint( 0.5 - a, 0.5 ) );
+    poly.append( ::basegfx::B2DPoint( 0.5, 0.5 + a ) );
+    poly.setClosed(true);
+    ::basegfx::B2DPolyPolygon res(poly);
+
+    // inner (reverse order to clip):
+    const double b = ::basegfx::pruneScaleValue( (1.0 - t) * 0.25 );
+    poly.clear();
+    poly.append( ::basegfx::B2DPoint( 0.5 + b, 0.5 ) );
+    poly.append( ::basegfx::B2DPoint( 0.5, 0.5 + b ) );
+    poly.append( ::basegfx::B2DPoint( 0.5 - b, 0.5 ) );
+    poly.append( ::basegfx::B2DPoint( 0.5, 0.5 - b ) );
+    poly.setClosed(true);
+    res.append(poly);
+
+    return res;
+}
+
+}
+
+/* vim:set shiftwidth=4 softtabstop=4 expandtab: */