Adding upstream version 4:7.4.7.upstream/4%7.4.7upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 111 insertions, 0 deletions

diff --git a/basegfx/source/tools/tools.cxx b/basegfx/source/tools/tools.cxx
new file mode 100644
index 000000000..4a7f2c962
--- /dev/null
+++ b/basegfx/source/tools/tools.cxx
@@ -0,0 +1,111 @@
+/* -*- 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/utils/tools.hxx>
+#include <basegfx/range/b2drange.hxx>
+
+#include <algorithm>
+
+namespace basegfx::utils
+{
+        namespace
+        {
+            double distance( const double&                   nX,
+                                    const double&                   nY,
+                                    const ::basegfx::B2DVector&     rNormal,
+                                    const double&                   nC )
+            {
+                return nX*rNormal.getX() + nY*rNormal.getY() - nC;
+            }
+
+            void moveLineOutsideRect( ::basegfx::B2DPoint&          io_rStart,
+                                      ::basegfx::B2DPoint&          io_rEnd,
+                                      const ::basegfx::B2DVector&   rMoveDirection,
+                                      const ::basegfx::B2DRange&    rFitTarget      )
+            {
+                // calc c for normal line form equation n x - c = 0
+                const double nC( rMoveDirection.scalar( io_rStart ) );
+
+                // calc maximum orthogonal distance for all four bound
+                // rect corners to the line
+                const double nMaxDistance( std::max(
+                                               0.0,
+                                               std::max(
+                                                   distance(rFitTarget.getMinX(),
+                                                            rFitTarget.getMinY(),
+                                                            rMoveDirection,
+                                                            nC),
+                                                   std::max(
+                                                       distance(rFitTarget.getMinX(),
+                                                                rFitTarget.getMaxY(),
+                                                                rMoveDirection,
+                                                                nC),
+                                                       std::max(
+                                                           distance(rFitTarget.getMaxX(),
+                                                                    rFitTarget.getMinY(),
+                                                                    rMoveDirection,
+                                                                    nC),
+                                                           distance(rFitTarget.getMaxX(),
+                                                                    rFitTarget.getMaxY(),
+                                                                    rMoveDirection,
+                                                                    nC) ) ) ) ) );
+
+                // now move line points, such that the bound rect
+                // points are all either 'on' or on the negative side
+                // of the half-plane
+                io_rStart += nMaxDistance*rMoveDirection;
+                io_rEnd   += nMaxDistance*rMoveDirection;
+            }
+        }
+
+        void infiniteLineFromParallelogram( ::basegfx::B2DPoint&        io_rLeftTop,
+                                            ::basegfx::B2DPoint&        io_rLeftBottom,
+                                            ::basegfx::B2DPoint&        io_rRightTop,
+                                            ::basegfx::B2DPoint&        io_rRightBottom,
+                                            const ::basegfx::B2DRange&  rFitTarget  )
+        {
+            // For the top and bottom border line of the
+            // parallelogram, we determine the distance to all four
+            // corner points of the bound rect (tl, tr, bl, br). When
+            // using the unit normal form for lines (n x - c = 0), and
+            // choosing n to point 'outwards' the parallelogram, then
+            // all bound rect corner points having positive distance
+            // to the line lie outside the extended gradient rect, and
+            // thus, the corresponding border line must be moved the
+            // maximum distance outwards.
+
+            // don't use the top and bottom border line direction, and
+            // calculate the normal from them. Instead, use the
+            // vertical lines (lt - lb or rt - rb), as they more
+            // faithfully represent the direction of the
+            // to-be-generated infinite line
+            ::basegfx::B2DVector aDirectionVertical( io_rLeftTop - io_rLeftBottom );
+            aDirectionVertical.normalize();
+
+            const ::basegfx::B2DVector aNormalTop( aDirectionVertical );
+            const ::basegfx::B2DVector aNormalBottom( -aDirectionVertical );
+
+            // now extend parallelogram, such that the bound rect
+            // point are included
+            moveLineOutsideRect( io_rLeftTop, io_rRightTop, aNormalTop, rFitTarget );
+            moveLineOutsideRect( io_rLeftBottom, io_rRightBottom, aNormalBottom, rFitTarget );
+        }
+}
+
+/* vim:set shiftwidth=4 softtabstop=4 expandtab: */