Delaunay 3D Manual
A Delaunay triangulation connects a set of points with lines so that a given point is connected to its neighbors. The 3D extension maxon::Delaunay3DInterface allows to fill the space between points with tetrahedrons.
The maxon::Delaunay3DInterface collects the given points and computes the tetrahedrons filling the space between these points.
An object is initialized with:
Points are added to the object with:
The calculation of the tetrahedrons is performed with:
The resulting geometry data is accessed with:
The tetrahedron containing a given point can be obtained with:
Miscellaneous functions are:
A maxon::Tetrahedron object represents a tetrahedron filling the space between the points of the Delaunay object. The class gives access to the tetrahedron's points and faces:
Further functions are:
// calculate size of the workspace which covers all points
// create Delaunay3DRef and perform tetrahedralization maxon::Delaunay3DRef delaunay3D = maxon::Delaunay3DRef::Create() iferr_return ; delaunay3D.Init(workspace) iferr_return ; delaunay3D.AddPointsIntoTetrahedralization(points) iferr_return ; delaunay3D.CalculateDelaunayTetrahedralization() iferr_return ;
// access resulting geometry const maxon ::BaseArray< maxon ::Tetrahedron>& tetrahedrons = delaunay3D.GetTetrahedrons(); const maxon ::BaseArray< 向量 >& pointsArray = delaunay3D.GetPoints(); maxon ::LinearCongruentialRandom< maxon :: Float32 > randomGen; // random generator for object colors const maxon :: Int tetrahedronPoints = 4; const maxon :: Int tetrahedronFaces = 4;
// for each tetrahedron create a PolygonObject for (const maxon ::Tetrahedron& tetrahedron : tetrahedrons) { // ignore tetrahedron that includes "internal" points (0 - 3) auto CheckTetra = [=]( const maxon::Tetrahedron & tetra) -> maxon::Bool { const maxon::Int internalVertice = 4; for ( maxon::Int i = 0; i < tetrahedronPoints; ++i) { if (tetra.points[i] < internalVertice) return false ; } return true ; };
// create PolygonObject for the given tetrahedron if (CheckTetra(tetrahedron)) { // alloc PolygonObject PolygonObject * const polyObject = PolygonObject::Alloc (tetrahedronPoints, tetrahedronFaces); if (polyObject != nullptr ) { CPolygon * const polygons = polyObject-> GetPolygonW (); 向量 * const polyPoints = polyObject-> GetPointW (); if (polygons && polyPoints) { // set vertices for ( maxon::Int i = 0; i < tetrahedronPoints; ++i) { const maxon::Int pointIndex = tetrahedron.points[i]; polyPoints[i] = pointsArray[pointIndex]; }
// set polygons for ( maxon::Int32 i = 0; i < tetrahedronFaces; ++i) { // get global face points maxon::IntVector32 tetraPoints; tetrahedron.GetFacePoints(i, tetraPoints); // set local points polygons[i]. a = tetrahedron.GetPointIndexOfPoint(tetraPoints. x ); polygons[i]. b = tetrahedron.GetPointIndexOfPoint(tetraPoints. y ); polygons[i]. c = tetrahedron.GetPointIndexOfPoint(tetraPoints. z ); polygons[i]. d = tetrahedron.GetPointIndexOfPoint(tetraPoints. z ); } }
// update geometry polyObject-> 消息 ( MSG_UPDATE );
// create random color auto GetRandomColor = [&randomGen]() -> maxon::Vector { maxon::Vector color; color. x = (randomGen.Get01() * 0.5) + 0.5; color. y = (randomGen.Get01() * 0.5) + 0.5; color. z = (randomGen.Get01() * 0.5) + 0.5; return color; };
// set object color polyObject-> SetParameter ( ID_BASEOBJECT_USECOLOR , ID_BASEOBJECT_USECOLOR_ALWAYS , DESCFLAGS_SET::NONE ); polyObject-> SetParameter ( ID_BASEOBJECT_COLOR , GetRandomColor(), DESCFLAGS_SET::NONE ); // insert object into the scene doc->InsertObject(polyObject, nullptr , nullptr ); } } }
