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, 144 insertions, 0 deletions

diff --git a/include/basegfx/polygon/b2dpolypolygoncutter.hxx b/include/basegfx/polygon/b2dpolypolygoncutter.hxx
new file mode 100644
index 000000000..55dd29cf8
--- /dev/null
+++ b/include/basegfx/polygon/b2dpolypolygoncutter.hxx
@@ -0,0 +1,144 @@
+/* -*- 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 .
+ */
+
+#pragma once
+
+#include <basegfx/polygon/b2dpolypolygon.hxx>
+#include <basegfx/basegfxdllapi.h>
+
+
+namespace basegfx::utils
+{
+        /** Solve all crossovers (aka self-intersections) in a polyPolygon.
+
+            This re-layouts all contained polygons so that the result
+            will contain only non-cutting polygons. For that reason,
+            points will be added at crossover and touch points and the
+            single Polygons may be re-combined. The orientations of
+            the contained polygons in not changed but used as
+            topological information.  Self crossovers of the contained
+            sub-polygons are implicitly handled, but to not lose the
+            topological information, it may be necessary to remove
+            self-intersections of the contained sub-polygons in a
+            preparing step and to explicitly correct their
+            orientations.
+        */
+        BASEGFX_DLLPUBLIC B2DPolyPolygon solveCrossovers(const B2DPolyPolygon& rCandidate,
+                                                         size_t* pPointLimit = nullptr);
+
+        /** Solve all crossovers (aka self-intersections) in a Polygon
+
+            Same as above, but for single polygons. Result will be
+            free of self-intersections. When result contains multiple
+            polygons, it may be necessary to rearrange their
+            orientations since holes may have been created (possibly use
+            correctOrientations).
+        */
+        BASEGFX_DLLPUBLIC B2DPolyPolygon solveCrossovers(const B2DPolygon& rCandidate);
+
+        /** Strip neutral polygons from PolyPolygon.
+
+            Neutral polygons are ones who's orientation is neutral, so
+            normally they have no volume -> just closed paths. A
+            polygon with the same positive and negative oriented
+            volume is also neutral, so this may not be wanted. It is
+            safe to call with self-intersection-free polygons, though
+            (that's where it's mostly used).
+        */
+        BASEGFX_DLLPUBLIC B2DPolyPolygon stripNeutralPolygons(const B2DPolyPolygon& rCandidate);
+
+        /** Remove unnecessary/non-displayed polygons.
+
+            Works only correct with self-intersection-free
+            polygons. For each polygon, the depth for the PolyPolygon
+            is calculated. The orientation is used to identify holes.
+            Start value for holes is -1, for polygons it's zero. Ech
+            time a polygon is contained in another one, it's depth is
+            increased when inside a polygon, decreased when inside a
+            hole. The result is a depth which e.g. is -1 for holes
+            outside everything, 1 for a polygon covered by another
+            polygon and zero for e.g. holes in a polygon or polygons
+            outside everything else.  In the 2nd step, all polygons
+            with depth other than zero are removed. If bKeepAboveZero
+            is used, all polygons < 1 are removed. The bKeepAboveZero
+            mode is useful for clipping, e.g. just append one polygon
+            to another and use this mode -> only parts where two
+            polygons overlapped will be kept.  In combination with
+            correct orientation of the input orientations and the
+            SolveCrossover calls this can be combined for logical
+            polygon operations or polygon clipping.
+        */
+        BASEGFX_DLLPUBLIC B2DPolyPolygon stripDispensablePolygons(const B2DPolyPolygon& rCandidate, bool bKeepAboveZero = false);
+
+        /** Emulate nonzero winding rule filling.
+
+            Geometrically convert PolyPolygons which are proposed to
+            use nonzero fill rule to a representation where evenodd
+            paint will give the same result. To do this all
+            intersections and self-intersections get solved (the
+            polygons will be rearranged if needed). Then all polygons
+            which are inside another one with the same orientation get
+            deleted
+        */
+        BASEGFX_DLLPUBLIC B2DPolyPolygon createNonzeroConform(const B2DPolyPolygon& rCandidate);
+
+        // For convenience: the four basic operations OR, XOR, AND and DIFF for
+        // two PolyPolygons. These are combinations of the above methods. To not be forced
+        // to do evtl. already done preparations twice, You have to do the operations Yourself.
+
+        // A source preparation consists of preparing it to be seen as XOR-Rule PolyPolygon,
+        // so it is freed of intersections, self-intersections and the orientations are corrected.
+        // Important is that it will define the same areas as before, but is intersection-free.
+        // As an example think about a single polygon looping in itself and having holes. To
+        // topologically correctly handle this, it is necessary to remove all intersections and
+        // to correct the orientations. The orientation of the isolated holes e.g. will be negative.
+        // Topologically it is necessary to prepare each polygon which is seen as entity. It is
+        // not sufficient just to concatenate them and prepare the result, this may be topologically
+        // different since the simple concatenation will be seen as XOR. To work correctly, You
+        // may need to OR those polygons.
+
+        /// prep for ops - solve self-intersections and intersections, remove neutral parts and check orientations.
+        BASEGFX_DLLPUBLIC B2DPolyPolygon prepareForPolygonOperation(const B2DPolygon& rCandidate);
+        /// prep for ops - solve self-intersections and intersections, remove neutral parts and check orientations.
+        BASEGFX_DLLPUBLIC B2DPolyPolygon prepareForPolygonOperation(const B2DPolyPolygon& rCandidate);
+
+        /// OR: Return all areas where CandidateA or CandidateB exist
+        BASEGFX_DLLPUBLIC B2DPolyPolygon solvePolygonOperationOr(const B2DPolyPolygon& rCandidateA, const B2DPolyPolygon& rCandidateB);
+
+        /// XOR: Return all areas where CandidateA or CandidateB exist, but not both
+        BASEGFX_DLLPUBLIC B2DPolyPolygon solvePolygonOperationXor(const B2DPolyPolygon& rCandidateA, const B2DPolyPolygon& rCandidateB);
+
+        /// AND: Return all areas where CandidateA and CandidateB exist
+        BASEGFX_DLLPUBLIC B2DPolyPolygon solvePolygonOperationAnd(const B2DPolyPolygon& rCandidateA, const B2DPolyPolygon& rCandidateB);
+
+        /// DIFF: Return all areas where CandidateA is not covered by CandidateB (cut B out of A)
+        BASEGFX_DLLPUBLIC B2DPolyPolygon solvePolygonOperationDiff(const B2DPolyPolygon& rCandidateA, const B2DPolyPolygon& rCandidateB);
+
+        /** merge all single PolyPolygons to a single, OR-ed PolyPolygon
+
+            @param rInput
+            The source PolyPolygons
+
+            @return A single tools::PolyPolygon containing the Or-merged result
+        */
+        BASEGFX_DLLPUBLIC B2DPolyPolygon mergeToSinglePolyPolygon(const B2DPolyPolygonVector& rInput);
+
+} // end of namespace basegfx::utils
+
+/* vim:set shiftwidth=4 softtabstop=4 expandtab: */