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diff --git a/include/basegfx/polygon/b2dpolygontools.hxx b/include/basegfx/polygon/b2dpolygontools.hxx new file mode 100644 index 000000000..40a4027a5 --- /dev/null +++ b/include/basegfx/polygon/b2dpolygontools.hxx @@ -0,0 +1,529 @@ +/* -*- 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 <vector> +#include <functional> + +#include <basegfx/point/b2dpoint.hxx> +#include <basegfx/vector/b2dvector.hxx> +#include <basegfx/range/b2drectangle.hxx> +#include <basegfx/polygon/b3dpolygon.hxx> +#include <basegfx/polygon/b2dpolygontriangulator.hxx> +#include <com/sun/star/drawing/PointSequence.hpp> +#include <com/sun/star/drawing/FlagSequence.hpp> +#include <basegfx/basegfxdllapi.h> +#include <o3tl/typed_flags_set.hxx> + + +namespace basegfx { class B2DPolyPolygon; } + +// Definitions for the cut flags used from the findCut methods +enum class CutFlagValue +{ + NONE = 0x0000, + LINE = 0x0001, + START1 = 0x0002, + START2 = 0x0004, + END1 = 0x0008, + END2 = 0x0010, + ALL = LINE|START1|START2|END1|END2, + DEFAULT = LINE|START2|END2, +}; +namespace o3tl +{ + template<> struct typed_flags<CutFlagValue> : is_typed_flags<CutFlagValue, 0x1f> {}; +} + +namespace basegfx +{ + class B2DPolygon; + class B2DRange; +} + +namespace basegfx::utils +{ + // B2DPolygon tools + + // open/close with point add/remove and control point corrections + BASEGFX_DLLPUBLIC void openWithGeometryChange(B2DPolygon& rCandidate); + BASEGFX_DLLPUBLIC void closeWithGeometryChange(B2DPolygon& rCandidate); + + /** Check if given polygon is closed. + + This is kind of a 'classic' method to support old polygon + definitions. Those old polygon definitions define the + closed state of the polygon using identical start and + endpoints. This method corrects this (removes double + start/end points) and sets the Closed()-state of the + polygon correctly. + */ + BASEGFX_DLLPUBLIC void checkClosed(B2DPolygon& rCandidate); + + // Get successor and predecessor indices. Returning the same index means there + // is none. Same for successor. + BASEGFX_DLLPUBLIC sal_uInt32 getIndexOfPredecessor(sal_uInt32 nIndex, const B2DPolygon& rCandidate); + BASEGFX_DLLPUBLIC sal_uInt32 getIndexOfSuccessor(sal_uInt32 nIndex, const B2DPolygon& rCandidate); + + // Get orientation of Polygon + BASEGFX_DLLPUBLIC B2VectorOrientation getOrientation(const B2DPolygon& rCandidate); + + // isInside tests for B2dPoint and other B2dPolygon. On border is not inside as long as + // not true is given in bWithBorder flag. + BASEGFX_DLLPUBLIC bool isInside(const B2DPolygon& rCandidate, const B2DPoint& rPoint, bool bWithBorder = false); + BASEGFX_DLLPUBLIC bool isInside(const B2DPolygon& rCandidate, const B2DPolygon& rPolygon, bool bWithBorder = false); + + /** Get the range of a polygon + + This method creates the outer range of the subdivided bezier curve. + For detailed discussion see B2DPolygon::getB2DRange() + + @param rCandidate + The B2DPolygon possibly containing bezier segments + + @return + The outer range of the bezier curve + */ + BASEGFX_DLLPUBLIC B2DRange getRange(const B2DPolygon& rCandidate); + + // get signed area of polygon + BASEGFX_DLLPUBLIC double getSignedArea(const B2DPolygon& rCandidate); + + // get area of polygon + BASEGFX_DLLPUBLIC double getArea(const B2DPolygon& rCandidate); + + /** get length of polygon edge from point nIndex to nIndex + 1 */ + BASEGFX_DLLPUBLIC double getEdgeLength(const B2DPolygon& rCandidate, sal_uInt32 nIndex); + + /** get length of polygon */ + BASEGFX_DLLPUBLIC double getLength(const B2DPolygon& rCandidate); + + // get position on polygon for absolute given distance. If + // length is given, it is assumed the correct polygon length, if 0.0 it is calculated + // using getLength(...) + BASEGFX_DLLPUBLIC B2DPoint getPositionAbsolute(const B2DPolygon& rCandidate, double fDistance, double fLength = 0.0); + + // get position on polygon for relative given distance in range [0.0 .. 1.0]. If + // length is given, it is assumed the correct polygon length, if 0.0 it is calculated + // using getLength(...) + BASEGFX_DLLPUBLIC B2DPoint getPositionRelative(const B2DPolygon& rCandidate, double fDistance, double fLength = 0.0); + + // get a snippet from given polygon for absolute distances. The polygon is assumed + // to be opened (not closed). fFrom and fTo need to be in range [0.0 .. fLength], where + // fTo >= fFrom. If length is given, it is assumed the correct polygon length, + // if 0.0 it is calculated using getLength(...) + BASEGFX_DLLPUBLIC B2DPolygon getSnippetAbsolute(const B2DPolygon& rCandidate, double fFrom, double fTo, double fLength = 0.0); + + // Continuity check for point with given index + BASEGFX_DLLPUBLIC B2VectorContinuity getContinuityInPoint(const B2DPolygon& rCandidate, sal_uInt32 nIndex); + + // Subdivide all contained curves. Use distanceBound value if given. + BASEGFX_DLLPUBLIC B2DPolygon adaptiveSubdivideByDistance(const B2DPolygon& rCandidate, double fDistanceBound); + + // Subdivide all contained curves. Use angleBound value if given. + BASEGFX_DLLPUBLIC B2DPolygon adaptiveSubdivideByAngle(const B2DPolygon& rCandidate, double fAngleBound = 0.0); + + // This version works with two points and vectors to define the + // edges for the cut test. + BASEGFX_DLLPUBLIC CutFlagValue findCut( + const B2DPoint& rEdge1Start, const B2DVector& rEdge1Delta, + const B2DPoint& rEdge2Start, const B2DVector& rEdge2Delta, + CutFlagValue aCutFlags = CutFlagValue::DEFAULT, + double* pCut1 = nullptr, double* pCut2 = nullptr); + + // test if point is on the given edge in range ]0.0..1.0[ without + // the start/end points. If so, return true and put the parameter + // value in pCut (if provided) + BASEGFX_DLLPUBLIC bool isPointOnEdge( + const B2DPoint& rPoint, + const B2DPoint& rEdgeStart, + const B2DVector& rEdgeDelta, + double* pCut = nullptr); + + /** Apply given LineDashing to given polygon + + This method is used to cut down line polygons to the needed + pieces when a dashing needs to be applied. + It is now capable of keeping contained bezier segments. + It is also capable of delivering line and non-line portions + depending on what target polygons You provide. This is useful + e.g. for dashed lines with two colors. + If the last and the first snippet in one of the results have + a common start/end ppoint, they will be merged to achieve as + view as needed result line snippets. This is also relevant for + further processing the results. + + @param rCandidate + The polygon based on which the snippets will be created. + + @param rDotDashArray + The line pattern given as array of length values + + @param pLineTarget + The target for line snippets, e.g. the first entry will be + a line segment with length rDotDashArray[0]. The given + polygon will be emptied as preparation. + + @param pGapTarget + The target for gap snippets, e.g. the first entry will be + a line segment with length rDotDashArray[1]. The given + polygon will be emptied as preparation. + + @param fFullDashDotLen + The summed-up length of the rDotDashArray. If zero, it will + be calculated internally. + + There is now a 2nd version that allows to provide callback + functions that get called when a snippet of a line/gap is + produced and needs to be added. This allows to use it like + a 'pipeline'. When using this (e.g. the 1st version uses + this internally to guarantee the same algorithm is used) + it is not needed to accumulate a potentially huge number + of polygons in the result-polyPolygons, but e.g. consume + them directly in the caller. Example is rendering a + dashed line but without creating the potentially huge amount + of polygons. + The 2nd version will also merge first/last line/gap snippets + if the input polygon is closed and the start/end-points match + accordingly - at the cost that this will be delivered last. + */ + BASEGFX_DLLPUBLIC void applyLineDashing( + const B2DPolygon& rCandidate, + const std::vector<double>& rDotDashArray, + std::function<void(const basegfx::B2DPolygon& rSnippet)> aLineTargetCallback, + std::function<void(const basegfx::B2DPolygon& rSnippet)> aGapTargetCallback = std::function<void(const basegfx::B2DPolygon&)>(), + double fDotDashLength = 0.0); + BASEGFX_DLLPUBLIC void applyLineDashing( + const B2DPolygon& rCandidate, + const ::std::vector<double>& rDotDashArray, + B2DPolyPolygon* pLineTarget, + B2DPolyPolygon* pGapTarget = nullptr, + double fDotDashLength = 0.0); + + // test if point is inside epsilon-range around an edge defined + // by the two given points. Can be used for HitTesting. The epsilon-range + // is defined to be the rectangle centered to the given edge, using height + // 2 x fDistance, and the circle around both points with radius fDistance. + BASEGFX_DLLPUBLIC bool isInEpsilonRange(const B2DPoint& rEdgeStart, const B2DPoint& rEdgeEnd, const B2DPoint& rTestPosition, double fDistance); + + // test if point is inside epsilon-range around the given Polygon. Can be used + // for HitTesting. The epsilon-range is defined to be the rectangle centered + // to the given edge, using height 2 x fDistance, and the circle around both points + // with radius fDistance. + BASEGFX_DLLPUBLIC bool isInEpsilonRange(const B2DPolygon& rCandidate, const B2DPoint& rTestPosition, double fDistance); + + /** Create a polygon from a rectangle. + + @param rRect + The rectangle which describes the polygon size + + @param fRadiusX + @param fRadiusY + Radius of the edge rounding, relative to the rectangle size. 0.0 means no + rounding, 1.0 will lead to an ellipse + */ + BASEGFX_DLLPUBLIC B2DPolygon createPolygonFromRect( const B2DRectangle& rRect, double fRadiusX, double fRadiusY ); + + /** Create a polygon from a rectangle. + */ + BASEGFX_DLLPUBLIC B2DPolygon createPolygonFromRect( const B2DRectangle& rRect ); + + /** Create the unit polygon + */ + BASEGFX_DLLPUBLIC B2DPolygon const & createUnitPolygon(); + + /** Create a circle polygon with given radius. + + This method creates a circle approximation consisting of + 12 cubic bezier segments, which approximate the given + circle with an error of less than 0.5 percent. + + @param rCenter + Center point of the circle + + @param fRadius + Radius of the circle + */ + BASEGFX_DLLPUBLIC B2DPolygon createPolygonFromCircle( const B2DPoint& rCenter, double fRadius ); + + /// create half circle centered on (0,0) from [0 .. F_PI] + B2DPolygon const & createHalfUnitCircle(); + + /** create a polygon which describes the unit circle and close it + + @param nStartQuadrant + To be able to rebuild the old behaviour where the circles started at bottom, + this parameter is used. Default is 0 which is the first quadrant and the + polygon's start point will be the rightmost one. When using e.g. 1, the + first created quadrant will start at the YMax-position (with Y down on screens, + this is the lowest one). This is needed since when lines are dashed, toe old + geometry started at bottom point, else it would look different. + */ + BASEGFX_DLLPUBLIC B2DPolygon const & createPolygonFromUnitCircle(sal_uInt32 nStartQuadrant = 0); + + /** Create an ellipse polygon with given radii. + + This method creates an ellipse approximation consisting of + 12 cubic bezier segments, which approximate the given + ellipse with an error of less than 0.5 percent. + + @param rCenter + Center point of the circle + + @param fRadiusX + Radius of the ellipse in X direction + + @param fRadiusY + Radius of the ellipse in Y direction + + @param nStartQuadrant + With Y down on screens, 0 = 3 o'clock, 1 = 6 o'clock, 2 = 9 o'clock, 3 = 12 o'clock + */ + BASEGFX_DLLPUBLIC B2DPolygon createPolygonFromEllipse( const B2DPoint& rCenter, double fRadiusX, double fRadiusY, sal_uInt32 nStartQuadrant = 0); + + /** Create a unit ellipse polygon with the given angles, from start to end + */ + BASEGFX_DLLPUBLIC B2DPolygon createPolygonFromEllipseSegment( const B2DPoint& rCenter, double fRadiusX, double fRadiusY, double fStart, double fEnd ); + + BASEGFX_DLLPUBLIC B2DPolygon createPolygonFromUnitEllipseSegment( double fStart, double fEnd ); + + /** Predicate whether a given polygon is a rectangle. + + @param rPoly + Polygon to check + + @return true, if the polygon describes a rectangle + (polygon is closed, and the points are either cw or ccw + enumerations of a rectangle's vertices). Note that + intermediate points and duplicate points are ignored. + */ + BASEGFX_DLLPUBLIC bool isRectangle( const B2DPolygon& rPoly ); + + // create 3d polygon from given 2d polygon. The given fZCoordinate is used to expand the + // third coordinate. + BASEGFX_DLLPUBLIC B3DPolygon createB3DPolygonFromB2DPolygon(const B2DPolygon& rCandidate, double fZCoordinate = 0.0); + + // create 2d tools::PolyPolygon from given 3d PolyPolygon. All coordinates are transformed using the given + // matrix and the resulting x,y is used to form the new polygon. + BASEGFX_DLLPUBLIC B2DPolygon createB2DPolygonFromB3DPolygon(const B3DPolygon& rCandidate, const B3DHomMatrix& rMat); + + // calculate the smallest distance to given edge and return. The relative position on the edge is returned in Cut. + // That position is in the range [0.0 .. 1.0] and the returned distance is adapted accordingly to the start or end + // point of the edge + BASEGFX_DLLPUBLIC double getSmallestDistancePointToEdge(const B2DPoint& rPointA, const B2DPoint& rPointB, const B2DPoint& rTestPoint, double& rCut); + + // for each contained edge calculate the smallest distance. Return the index to the smallest + // edge in rEdgeIndex. The relative position on the edge is returned in rCut. + // If nothing was found (e.g. empty input plygon), DBL_MAX is returned. + BASEGFX_DLLPUBLIC double getSmallestDistancePointToPolygon(const B2DPolygon& rCandidate, const B2DPoint& rTestPoint, sal_uInt32& rEdgeIndex, double& rCut); + + // distort single point. rOriginal describes the original range, where the given points describe the distorted corresponding points. + BASEGFX_DLLPUBLIC B2DPoint distort(const B2DPoint& rCandidate, const B2DRange& rOriginal, const B2DPoint& rTopLeft, const B2DPoint& rTopRight, const B2DPoint& rBottomLeft, const B2DPoint& rBottomRight); + + // distort polygon. rOriginal describes the original range, where the given points describe the distorted corresponding points. + BASEGFX_DLLPUBLIC B2DPolygon distort(const B2DPolygon& rCandidate, const B2DRange& rOriginal, const B2DPoint& rTopLeft, const B2DPoint& rTopRight, const B2DPoint& rBottomLeft, const B2DPoint& rBottomRight); + + // expand all segments (which are not yet) to curve segments. This is done with setting the control + // vectors on the 1/3 resp. 2/3 distances on each segment. + BASEGFX_DLLPUBLIC B2DPolygon expandToCurve(const B2DPolygon& rCandidate); + + // expand given segment to curve segment. This is done with setting the control + // vectors on the 1/3 resp. 2/3 distances. The return value describes if a change took place. + BASEGFX_DLLPUBLIC bool expandToCurveInPoint(B2DPolygon& rCandidate, sal_uInt32 nIndex); + + // set continuity for given index. If not a curve, nothing will change. Non-curve points are not changed, too. + // The return value describes if a change took place. + BASEGFX_DLLPUBLIC bool setContinuityInPoint(B2DPolygon& rCandidate, sal_uInt32 nIndex, B2VectorContinuity eContinuity); + + // test if polygon contains neutral points. A neutral point is one whose orientation is neutral + // e.g. positioned on the edge of its predecessor and successor + BASEGFX_DLLPUBLIC bool hasNeutralPoints(const B2DPolygon& rCandidate); + + // remove neutral points. A neutral point is one whose orientation is neutral + // e.g. positioned on the edge of its predecessor and successor + BASEGFX_DLLPUBLIC B2DPolygon removeNeutralPoints(const B2DPolygon& rCandidate); + + // tests if polygon is convex + BASEGFX_DLLPUBLIC bool isConvex(const B2DPolygon& rCandidate); + + // calculates the orientation at edge nIndex + BASEGFX_DLLPUBLIC B2VectorOrientation getOrientationForIndex(const B2DPolygon& rCandidate, sal_uInt32 nIndex); + + // calculates if given point is on given line, taking care of the numerical epsilon + BASEGFX_DLLPUBLIC bool isPointOnLine(const B2DPoint& rStart, const B2DPoint& rEnd, const B2DPoint& rCandidate, bool bWithPoints); + + // calculates if given point is on given polygon, taking care of the numerical epsilon. Uses + // isPointOnLine internally + BASEGFX_DLLPUBLIC bool isPointOnPolygon(const B2DPolygon& rCandidate, const B2DPoint& rPoint, bool bWithPoints = true); + + // test if candidate is inside triangle + BASEGFX_DLLPUBLIC bool isPointInTriangle(const B2DPoint& rA, const B2DPoint& rB, const B2DPoint& rC, const B2DPoint& rCandidate, bool bWithBorder); + + // test if candidateA and candidateB are on the same side of the given line + BASEGFX_DLLPUBLIC bool arePointsOnSameSideOfLine(const B2DPoint& rStart, const B2DPoint& rEnd, const B2DPoint& rCandidateA, const B2DPoint& rCandidateB, bool bWithLine); + + // add triangles for given rCandidate to rTarget. For each triangle, 3 points will be added to rCandidate. + // All triangles will go from the start point of rCandidate to two consecutive points, building (rCandidate.count() - 2) + // triangles. + BASEGFX_DLLPUBLIC void addTriangleFan( + const B2DPolygon& rCandidate, + triangulator::B2DTriangleVector& rTarget); + + // grow for polygon. Move all geometry in each point in the direction of the normal in that point + // with the given amount. Value may be negative. + BASEGFX_DLLPUBLIC B2DPolygon growInNormalDirection(const B2DPolygon& rCandidate, double fValue); + + // force all sub-polygons to a point count of nSegments + BASEGFX_DLLPUBLIC B2DPolygon reSegmentPolygon(const B2DPolygon& rCandidate, sal_uInt32 nSegments); + + // create polygon state at t from 0.0 to 1.0 between the two polygons. Both polygons must have the same + // organisation, e.g. same amount of points + BASEGFX_DLLPUBLIC B2DPolygon interpolate(const B2DPolygon& rOld1, const B2DPolygon& rOld2, double t); + + // #i76891# Try to remove existing curve segments if they are simply edges + BASEGFX_DLLPUBLIC B2DPolygon simplifyCurveSegments(const B2DPolygon& rCandidate); + + // makes the given indexed point the new polygon start point. To do that, the points in the + // polygon will be rotated. This is only valid for closed polygons, for non-closed ones + // an assertion will be triggered + BASEGFX_DLLPUBLIC B2DPolygon makeStartPoint(const B2DPolygon& rCandidate, sal_uInt32 nIndexOfNewStatPoint); + + /** create edges of given length along given B2DPolygon + + @param rCandidate + The polygon to move along. Points at the given polygon are created, starting + at position fStart and stopping at less or equal to fEnd. The closed state is + preserved. + The polygon is subdivided if curve segments are included. That subdivision is the base + for the newly created points. + If the source is closed, the indirectly existing last edge may NOT have the + given length. + If the source is open, all edges will have the given length. You may use the last + point of the original when You want to add the last edge Yourself. + + @param fLength + The length of the created edges. If less or equal zero, an empty polygon is returned. + + @param fStart + The start distance for the first to be generated point. Use 0.0 to get the + original start point. Negative values are truncated to 0.0. + + @param fEnd + The maximum distance for the last point. No more points behind this distance will be created. + Use 0.0 to process the whole polygon. Negative values are truncated to 0.0. It also + needs to be more or equal to fStart, else it is truncated to fStart. + + @return + The newly created polygon + */ + BASEGFX_DLLPUBLIC B2DPolygon createEdgesOfGivenLength(const B2DPolygon& rCandidate, double fLength, double fStart = 0.0, double fEnd = 0.0); + + /** Create Waveline along given polygon + The implementation is based on createEdgesOfGivenLength and creates a curve + segment with the given dimensions for each created line segment. The polygon + is treated as if opened (closed state will be ignored) and only for whole + edges a curve segment will be created (no rest handling) + + @param rCandidate + The polygon along which the waveline will be created + + @param fWaveWidth + The length of a single waveline curve segment + + @param fgWaveHeight + The height of the waveline (amplitude) + */ + BASEGFX_DLLPUBLIC B2DPolygon createWaveline(const B2DPolygon& rCandidate, double fWaveWidth, double fWaveHeight); + + /** snap some polygon coordinates to discrete coordinates + + This method allows to snap some polygon points to discrete (integer) values + which equals e.g. a snap to discrete coordinates. It will snap points of + horizontal and vertical edges + + @param rCandidate + The source polygon + + @return + The modified version of the source polygon + */ + BASEGFX_DLLPUBLIC B2DPolygon snapPointsOfHorizontalOrVerticalEdges(const B2DPolygon& rCandidate); + + /// get the tangent with which the given point is entered seen from the previous + /// polygon path data. Take into account all stuff like closed state, zero-length edges and others. + BASEGFX_DLLPUBLIC B2DVector getTangentEnteringPoint(const B2DPolygon& rCandidate, sal_uInt32 nIndex); + + /// get the tangent with which the given point is left seen from the following + /// polygon path data. Take into account all stuff like closed state, zero-length edges and others. + BASEGFX_DLLPUBLIC B2DVector getTangentLeavingPoint(const B2DPolygon& rCandidate, sal_uInt32 nIndex); + + /// converters for css::drawing::PointSequence + BASEGFX_DLLPUBLIC B2DPolygon UnoPointSequenceToB2DPolygon( + const css::drawing::PointSequence& rPointSequenceSource); + BASEGFX_DLLPUBLIC void B2DPolygonToUnoPointSequence( + const B2DPolygon& rPolygon, + css::drawing::PointSequence& rPointSequenceRetval); + + /* converters for css::drawing::PointSequence and + css::drawing::FlagSequence to B2DPolygon (curved polygons) + */ + B2DPolygon UnoPolygonBezierCoordsToB2DPolygon( + const css::drawing::PointSequence& rPointSequenceSource, + const css::drawing::FlagSequence& rFlagSequenceSource); + void B2DPolygonToUnoPolygonBezierCoords( + const B2DPolygon& rPolyPolygon, + css::drawing::PointSequence& rPointSequenceRetval, + css::drawing::FlagSequence& rFlagSequenceRetval); + + /** Read poly-polygon from SVG. + + This function imports a poly-polygon from an SVG points + attribute (a plain list of coordinate pairs). + + @param o_rPoly + The output polygon. Note that svg:points can only define a + single polygon + + @param rSvgPointsAttribute + A valid SVG points attribute string + + @return true, if the string was successfully parsed + */ + BASEGFX_DLLPUBLIC bool importFromSvgPoints( B2DPolygon& o_rPoly, + const OUString& rSvgPointsAttribute ); + + /** Write poly-polygon to SVG. + + This function imports a non-bezier polygon to SVG points + (a plain list of coordinate pairs). + + @param rPoly + The polygon to export + + @param rSvgPointsAttribute + A valid SVG points attribute string + + @return true, if the string was successfully parsed + */ + BASEGFX_DLLPUBLIC OUString exportToSvgPoints( const B2DPolygon& rPoly ); + +} // end of namespace basegfx::utils + +/* vim:set shiftwidth=4 softtabstop=4 expandtab: */ |