xref: /aoo4110/main/basegfx/source/polygon/b3dpolygonclipper.cxx (revision b1cdbd2c)

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 *
 * 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
 *
 * Unless required by applicable law or agreed to in writing,
 * software distributed under the License is distributed on an
 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
 * KIND, either express or implied.  See the License for the
 * specific language governing permissions and limitations
 * under the License.
 *
 *************************************************************/



// MARKER(update_precomp.py): autogen include statement, do not remove
#include "precompiled_basegfx.hxx"

#include <basegfx/polygon/b3dpolygonclipper.hxx>
#include <osl/diagnose.h>
#include <basegfx/polygon/b3dpolygontools.hxx>
#include <basegfx/numeric/ftools.hxx>
#include <basegfx/matrix/b3dhommatrix.hxx>
#include <basegfx/polygon/b3dpolygontools.hxx>
#include <basegfx/range/b3drange.hxx>
#include <basegfx/point/b2dpoint.hxx>
#include <basegfx/range/b2drange.hxx>
#include <basegfx/color/bcolor.hxx>

//////////////////////////////////////////////////////////////////////////////

namespace basegfx
{
	namespace
	{
		inline bool impIsInside(const B3DPoint& rCandidate, double fPlaneOffset, tools::B3DOrientation ePlaneOrthogonal)
		{
			if(tools::B3DORIENTATION_X == ePlaneOrthogonal)
			{
				return fTools::moreOrEqual(rCandidate.getX(), fPlaneOffset);
			}
			else if(tools::B3DORIENTATION_Y == ePlaneOrthogonal)
			{
				return fTools::moreOrEqual(rCandidate.getY(), fPlaneOffset);
			}
			else
			{
				return fTools::moreOrEqual(rCandidate.getZ(), fPlaneOffset);
			}
		}

		inline double impGetCut(const B3DPoint& rCurrent, const B3DPoint& rNext, double fPlaneOffset, tools::B3DOrientation ePlaneOrthogonal)
		{
			if(tools::B3DORIENTATION_X == ePlaneOrthogonal)
			{
				return ((fPlaneOffset - rCurrent.getX())/(rNext.getX() - rCurrent.getX()));
			}
			else if(tools::B3DORIENTATION_Y == ePlaneOrthogonal)
			{
				return ((fPlaneOffset - rCurrent.getY())/(rNext.getY() - rCurrent.getY()));
			}
			else
			{
				return ((fPlaneOffset - rCurrent.getZ())/(rNext.getZ() - rCurrent.getZ()));
			}
		}

		void impAppendCopy(B3DPolygon& rDest, const B3DPolygon& rSource, sal_uInt32 nIndex)
		{
			rDest.append(rSource.getB3DPoint(nIndex));

			if(rSource.areBColorsUsed())
			{
				rDest.setBColor(rDest.count() - 1L, rSource.getBColor(nIndex));
			}

			if(rSource.areNormalsUsed())
			{
				rDest.setNormal(rDest.count() - 1L, rSource.getNormal(nIndex));
			}

			if(rSource.areTextureCoordinatesUsed())
			{
				rDest.setTextureCoordinate(rDest.count() - 1L, rSource.getTextureCoordinate(nIndex));
			}
		}

		void impAppendInterpolate(B3DPolygon& rDest, const B3DPolygon& rSource, sal_uInt32 nIndA, sal_uInt32 nIndB, double fCut)
		{
			const B3DPoint aCurrPoint(rSource.getB3DPoint(nIndA));
			const B3DPoint aNextPoint(rSource.getB3DPoint(nIndB));
			rDest.append(interpolate(aCurrPoint, aNextPoint, fCut));

			if(rSource.areBColorsUsed())
			{
				const BColor aCurrBColor(rSource.getBColor(nIndA));
				const BColor aNextBColor(rSource.getBColor(nIndB));
				rDest.setBColor(rDest.count() - 1L, interpolate(aCurrBColor, aNextBColor, fCut));
			}

			if(rSource.areNormalsUsed())
			{
				const B3DVector aCurrVector(rSource.getNormal(nIndA));
				const B3DVector aNextVector(rSource.getNormal(nIndB));
				rDest.setNormal(rDest.count() - 1L, interpolate(aCurrVector, aNextVector, fCut));
			}

			if(rSource.areTextureCoordinatesUsed())
			{
				const B2DPoint aCurrTxCo(rSource.getTextureCoordinate(nIndA));
				const B2DPoint aNextTxCo(rSource.getTextureCoordinate(nIndB));
				rDest.setTextureCoordinate(rDest.count() - 1L, interpolate(aCurrTxCo, aNextTxCo, fCut));
			}
		}
	}
} // end of namespace basegfx

//////////////////////////////////////////////////////////////////////////////

namespace basegfx
{
	namespace tools
	{
		B3DPolyPolygon clipPolygonOnOrthogonalPlane(const B3DPolygon& rCandidate, B3DOrientation ePlaneOrthogonal, bool bClipPositive, double fPlaneOffset, bool bStroke)
		{
			B3DPolyPolygon aRetval;

			if(rCandidate.count())
			{
				const B3DRange aCandidateRange(getRange(rCandidate));

				if(B3DORIENTATION_X == ePlaneOrthogonal && fTools::moreOrEqual(aCandidateRange.getMinX(), fPlaneOffset))
				{
					// completely above and on the clip plane.
					if(bClipPositive)
					{
						// add completely
						aRetval.append(rCandidate);
					}
				}
				else if(B3DORIENTATION_X == ePlaneOrthogonal && fTools::lessOrEqual(aCandidateRange.getMaxX(), fPlaneOffset))
				{
					// completely below and on the clip plane.
					if(!bClipPositive)
					{
						// add completely
						aRetval.append(rCandidate);
					}
				}
				else if(B3DORIENTATION_Y == ePlaneOrthogonal && fTools::moreOrEqual(aCandidateRange.getMinY(), fPlaneOffset))
				{
					// completely above and on the clip plane.
					if(bClipPositive)
					{
						// add completely
						aRetval.append(rCandidate);
					}
				}
				else if(B3DORIENTATION_Y == ePlaneOrthogonal && fTools::lessOrEqual(aCandidateRange.getMaxY(), fPlaneOffset))
				{
					// completely below and on the clip plane.
					if(!bClipPositive)
					{
						// add completely
						aRetval.append(rCandidate);
					}
				}
				else if(B3DORIENTATION_Z == ePlaneOrthogonal && fTools::moreOrEqual(aCandidateRange.getMinZ(), fPlaneOffset))
				{
					// completely above and on the clip plane.
					if(bClipPositive)
					{
						// add completely
						aRetval.append(rCandidate);
					}
				}
				else if(B3DORIENTATION_Z == ePlaneOrthogonal && fTools::lessOrEqual(aCandidateRange.getMaxZ(), fPlaneOffset))
				{
					// completely below and on the clip plane.
					if(!bClipPositive)
					{
						// add completely
						aRetval.append(rCandidate);
					}
				}
				else
				{
					// prepare loop(s)
					B3DPolygon aNewPolygon;
					B3DPoint aCurrent(rCandidate.getB3DPoint(0L));
					const sal_uInt32 nPointCount(rCandidate.count());
					const sal_uInt32 nEdgeCount(rCandidate.isClosed() ? nPointCount : nPointCount - 1L);
					bool bCurrentInside(impIsInside(aCurrent, fPlaneOffset, ePlaneOrthogonal) == bClipPositive);

					if(bCurrentInside)
					{
						impAppendCopy(aNewPolygon, rCandidate, 0L);
					}

					if(bStroke)
					{
						// open polygon, create clipped line snippets.
						for(sal_uInt32 a(0L); a < nEdgeCount; a++)
						{
							// get next point data
							const sal_uInt32 nNextIndex((a + 1L == nPointCount) ? 0L : a + 1L);
							const B3DPoint aNext(rCandidate.getB3DPoint(nNextIndex));
							const bool bNextInside(impIsInside(aNext, fPlaneOffset, ePlaneOrthogonal) == bClipPositive);

							if(bCurrentInside != bNextInside)
							{
								// change inside/outside
								if(bNextInside)
								{
									// entering, finish existing and start new line polygon
									if(aNewPolygon.count() > 1L)
									{
										aRetval.append(aNewPolygon);
									}

									aNewPolygon.clear();
								}

								// calculate and add cut point
								const double fCut(impGetCut(aCurrent, aNext, fPlaneOffset, ePlaneOrthogonal));
								impAppendInterpolate(aNewPolygon, rCandidate, a, nNextIndex, fCut);

								// pepare next step
								bCurrentInside = bNextInside;
							}

							if(bNextInside)
							{
								impAppendCopy(aNewPolygon, rCandidate, nNextIndex);
							}

							// pepare next step
							aCurrent = aNext;
						}

						if(aNewPolygon.count() > 1L)
						{
							aRetval.append(aNewPolygon);
						}
					}
					else
					{
						// closed polygon, create single clipped closed polygon
						for(sal_uInt32 a(0L); a < nEdgeCount; a++)
						{
							// get next point data, use offset
							const sal_uInt32 nNextIndex((a + 1L == nPointCount) ? 0L : a + 1L);
							const B3DPoint aNext(rCandidate.getB3DPoint(nNextIndex));
							const bool bNextInside(impIsInside(aNext, fPlaneOffset, ePlaneOrthogonal) == bClipPositive);

							if(bCurrentInside != bNextInside)
							{
								// calculate and add cut point
								const double fCut(impGetCut(aCurrent, aNext, fPlaneOffset, ePlaneOrthogonal));
								impAppendInterpolate(aNewPolygon, rCandidate, a, nNextIndex, fCut);

								// pepare next step
								bCurrentInside = bNextInside;
							}

							if(bNextInside && nNextIndex)
							{
								impAppendCopy(aNewPolygon, rCandidate, nNextIndex);
							}

							// pepare next step
							aCurrent = aNext;
						}

						if(aNewPolygon.count() > 2L)
						{
							aNewPolygon.setClosed(true);
							aRetval.append(aNewPolygon);
						}
					}
				}
			}

			return aRetval;
		}

		B3DPolyPolygon clipPolyPolygonOnOrthogonalPlane(const B3DPolyPolygon& rCandidate, B3DOrientation ePlaneOrthogonal, bool bClipPositive, double fPlaneOffset, bool bStroke)
		{
			B3DPolyPolygon aRetval;

			for(sal_uInt32 a(0L); a < rCandidate.count(); a++)
			{
				aRetval.append(clipPolygonOnOrthogonalPlane(rCandidate.getB3DPolygon(a), ePlaneOrthogonal, bClipPositive, fPlaneOffset, bStroke));
			}

			return aRetval;
		}

		B3DPolyPolygon clipPolyPolygonOnRange(const B3DPolyPolygon& rCandidate, const B2DRange& rRange, bool bInside, bool bStroke)
		{
			B3DPolyPolygon aRetval;

			for(sal_uInt32 a(0L); a < rCandidate.count(); a++)
			{
				aRetval.append(clipPolygonOnRange(rCandidate.getB3DPolygon(a), rRange, bInside, bStroke));
			}

			return aRetval;
		}

		B3DPolyPolygon clipPolygonOnRange(const B3DPolygon& rCandidate, const B2DRange& rRange, bool bInside, bool bStroke)
		{
			B3DPolyPolygon aRetval;

			if(rRange.isEmpty())
			{
				// clipping against an empty range. Nothing is inside an empty range, so the polygon
				// is outside the range. So only return if not inside is wanted
				if(!bInside && rCandidate.count())
				{
					aRetval.append(rCandidate);
				}
			}
			else if(rCandidate.count())
			{
				const B3DRange aCandidateRange3D(getRange(rCandidate));
				const B2DRange aCandidateRange(
					aCandidateRange3D.getMinX(), aCandidateRange3D.getMinY(),
					aCandidateRange3D.getMaxX(), aCandidateRange3D.getMaxY());

				if(rRange.isInside(aCandidateRange))
				{
					// candidate is completely inside given range, nothing to do. Is also true with curves.
					if(bInside)
					{
						aRetval.append(rCandidate);
					}
				}
				else if(!rRange.overlaps(aCandidateRange))
				{
					// candidate is completely outside given range, nothing to do. Is also true with curves.
					if(!bInside)
					{
						aRetval.append(rCandidate);
					}
				}
				else
				{
					// clip against the six planes of the range
					// against lower X
					aRetval = clipPolygonOnOrthogonalPlane(rCandidate, tools::B3DORIENTATION_X, bInside, rRange.getMinX(), bStroke);

					if(aRetval.count())
					{
						// against lower Y
						if(1L == aRetval.count())
						{
							aRetval = clipPolygonOnOrthogonalPlane(aRetval.getB3DPolygon(0L), tools::B3DORIENTATION_Y, bInside, rRange.getMinY(), bStroke);
						}
						else
						{
							aRetval = clipPolyPolygonOnOrthogonalPlane(aRetval, tools::B3DORIENTATION_Y, bInside, rRange.getMinY(), bStroke);
						}

						if(aRetval.count())
						{
							// against higher X
							if(1L == aRetval.count())
							{
								aRetval = clipPolygonOnOrthogonalPlane(aRetval.getB3DPolygon(0L), tools::B3DORIENTATION_X, !bInside, rRange.getMaxX(), bStroke);
							}
							else
							{
								aRetval = clipPolyPolygonOnOrthogonalPlane(aRetval, tools::B3DORIENTATION_X, !bInside, rRange.getMaxX(), bStroke);
							}

							if(aRetval.count())
							{
								// against higher Y
								if(1L == aRetval.count())
								{
									aRetval = clipPolygonOnOrthogonalPlane(aRetval.getB3DPolygon(0L), tools::B3DORIENTATION_Y, !bInside, rRange.getMaxY(), bStroke);
								}
								else
								{
									aRetval = clipPolyPolygonOnOrthogonalPlane(aRetval, tools::B3DORIENTATION_Y, !bInside, rRange.getMaxY(), bStroke);
								}
							}
						}
					}
				}
			}

			return aRetval;
		}

		B3DPolyPolygon clipPolyPolygonOnRange(const B3DPolyPolygon& rCandidate, const B3DRange& rRange, bool bInside, bool bStroke)
		{
			B3DPolyPolygon aRetval;

			for(sal_uInt32 a(0L); a < rCandidate.count(); a++)
			{
				aRetval.append(clipPolygonOnRange(rCandidate.getB3DPolygon(a), rRange, bInside, bStroke));
			}

			return aRetval;
		}

		B3DPolyPolygon clipPolygonOnRange(const B3DPolygon& rCandidate, const B3DRange& rRange, bool bInside, bool bStroke)
		{
			B3DPolyPolygon aRetval;

			if(rRange.isEmpty())
			{
				// clipping against an empty range. Nothing is inside an empty range, so the polygon
				// is outside the range. So only return if not inside is wanted
				if(!bInside && rCandidate.count())
				{
					aRetval.append(rCandidate);
				}
			}
			else if(rCandidate.count())
			{
				const B3DRange aCandidateRange(getRange(rCandidate));

				if(rRange.isInside(aCandidateRange))
				{
					// candidate is completely inside given range, nothing to do. Is also true with curves.
					if(bInside)
					{
						aRetval.append(rCandidate);
					}
				}
				else if(!rRange.overlaps(aCandidateRange))
				{
					// candidate is completely outside given range, nothing to do. Is also true with curves.
					if(!bInside)
					{
						aRetval.append(rCandidate);
					}
				}
				else
				{
					// clip against X,Y first and see if there's something left
					const B2DRange aCandidateRange2D(rRange.getMinX(), rRange.getMinY(), rRange.getMaxX(), rRange.getMaxY());
					aRetval = clipPolygonOnRange(rCandidate, aCandidateRange2D, bInside, bStroke);

					if(aRetval.count())
					{
						// against lower Z
						if(1L == aRetval.count())
						{
							aRetval = clipPolygonOnOrthogonalPlane(aRetval.getB3DPolygon(0L), tools::B3DORIENTATION_Z, bInside, rRange.getMinZ(), bStroke);
						}
						else
						{
							aRetval = clipPolyPolygonOnOrthogonalPlane(aRetval, tools::B3DORIENTATION_Z, bInside, rRange.getMinZ(), bStroke);
						}

						if(aRetval.count())
						{
							// against higher Z
							if(1L == aRetval.count())
							{
								aRetval = clipPolygonOnOrthogonalPlane(aRetval.getB3DPolygon(0L), tools::B3DORIENTATION_Z, !bInside, rRange.getMaxZ(), bStroke);
							}
							else
							{
								aRetval = clipPolyPolygonOnOrthogonalPlane(aRetval, tools::B3DORIENTATION_Z, !bInside, rRange.getMaxZ(), bStroke);
							}
						}
					}
				}
			}

			return aRetval;
		}

		B3DPolyPolygon clipPolygonOnPlane(const B3DPolygon& rCandidate, const B3DPoint& rPointOnPlane, const B3DVector& rPlaneNormal, bool bClipPositive, bool bStroke)
		{
			B3DPolyPolygon aRetval;

			if(rPlaneNormal.equalZero())
			{
				// not really a plane definition, return polygon
				aRetval.append(rCandidate);
			}
			else if(rCandidate.count())
			{
				// build transform to project planeNormal on X-Axis and pointOnPlane to null point
				B3DHomMatrix aMatrixTransform;
				aMatrixTransform.translate(-rPointOnPlane.getX(), -rPointOnPlane.getY(), -rPointOnPlane.getZ());
				const double fRotInXY(atan2(rPlaneNormal.getY(), rPlaneNormal.getX()));
				const double fRotInXZ(atan2(-rPlaneNormal.getZ(), rPlaneNormal.getXYLength()));
				if(!fTools::equalZero(fRotInXY) || !fTools::equalZero(fRotInXZ))
				{
					aMatrixTransform.rotate(0.0, fRotInXZ, fRotInXY);
				}

				// transform polygon to clip scenario
				B3DPolygon aCandidate(rCandidate);
				aCandidate.transform(aMatrixTransform);

				// clip on YZ plane
				aRetval = clipPolygonOnOrthogonalPlane(aCandidate, tools::B3DORIENTATION_X, bClipPositive, 0.0, bStroke);

				if(aRetval.count())
				{
					// if there is a result, it needs to be transformed back
					aMatrixTransform.invert();
					aRetval.transform(aMatrixTransform);
				}
			}

			return aRetval;
		}

		B3DPolyPolygon clipPolyPolygonOnPlane(const B3DPolyPolygon& rCandidate, const B3DPoint& rPointOnPlane, const B3DVector& rPlaneNormal, bool bClipPositive, bool bStroke)
		{
			B3DPolyPolygon aRetval;

			if(rPlaneNormal.equalZero())
			{
				// not really a plane definition, return polygon
				aRetval = rCandidate;
			}
			else if(rCandidate.count())
			{
				// build transform to project planeNormal on X-Axis and pointOnPlane to null point
				B3DHomMatrix aMatrixTransform;
				aMatrixTransform.translate(-rPointOnPlane.getX(), -rPointOnPlane.getY(), -rPointOnPlane.getZ());
				const double fRotInXY(atan2(rPlaneNormal.getY(), rPlaneNormal.getX()));
				const double fRotInXZ(atan2(-rPlaneNormal.getZ(), rPlaneNormal.getXYLength()));
				if(!fTools::equalZero(fRotInXY) || !fTools::equalZero(fRotInXZ))
				{
					aMatrixTransform.rotate(0.0, fRotInXZ, fRotInXY);
				}

				// transform polygon to clip scenario
				aRetval = rCandidate;
				aRetval.transform(aMatrixTransform);

				// clip on YZ plane
				aRetval = clipPolyPolygonOnOrthogonalPlane(aRetval, tools::B3DORIENTATION_X, bClipPositive, 0.0, bStroke);

				if(aRetval.count())
				{
					// if there is a result, it needs to be transformed back
					aMatrixTransform.invert();
					aRetval.transform(aMatrixTransform);
				}
			}

			return aRetval;
		}

	} // end of namespace tools
} // end of namespace basegfx

//////////////////////////////////////////////////////////////////////////////

// eof