src/SelectMgr/SelectMgr_Frustum.hxx

   1 // Created on: 2015-03-16
   2 // Created by: Varvara POSKONINA
   3 // Copyright (c) 2005-2014 OPEN CASCADE SAS
   4 //
   5 // This file is part of Open CASCADE Technology software library.
   6 //
   7 // This library is free software; you can redistribute it and/or modify it under
   8 // the terms of the GNU Lesser General Public License version 2.1 as published
   9 // by the Free Software Foundation, with special exception defined in the file
  10 // OCCT_LGPL_EXCEPTION.txt. Consult the file LICENSE_LGPL_21.txt included in OCCT
  11 // distribution for complete text of the license and disclaimer of any warranty.
  12 //
  13 // Alternatively, this file may be used under the terms of Open CASCADE
  14 // commercial license or contractual agreement.
  15
  16 #ifndef _SelectMgr_Frustum_HeaderFile
  17 #define _SelectMgr_Frustum_HeaderFile
  18
  19 #include <SelectMgr_BaseFrustum.hxx>
  20
  21 //! This is an internal class containing representation of rectangular selecting frustum, created in case
  22 //! of point and box selection, and algorithms for overlap detection between selecting
  23 //! frustum and sensitive entities. The principle of frustum calculation:
  24 //! - for point selection: on a near view frustum plane rectangular neighborhood of
  25 //!                        user-picked point is created according to the pixel tolerance
  26 //!                        given and then this rectangle is projected onto far view frustum
  27 //!                        plane. This rectangles define the parallel bases of selecting frustum;
  28 //! - for box selection: box points are projected onto near and far view frustum planes.
  29 //!                      These 2 projected rectangles define parallel bases of selecting frustum.
  30 //! Overlap detection tests are implemented according to the terms of separating axis
  31 //! theorem (SAT).
  32 //! Vertex order:
  33 //! - for triangular frustum: V0_Near, V1_Near, V2_Near,
  34 //!                           V0_Far, V1_Far, V2_Far;
  35 //! - for rectangular frustum: LeftTopNear, LeftTopFar,
  36 //!                            LeftBottomNear,LeftBottomFar,
  37 //!                            RightTopNear, RightTopFar,
  38 //!                            RightBottomNear, RightBottomFar.
  39 //! Plane order in array:
  40 //! - for triangular frustum: V0V1, V1V2, V0V2, Near, Far;
  41 //! - for rectangular frustum: Top, Bottom, Left, Right, Near, Far.
  42 //! Uncollinear edge directions order:
  43 //! - for rectangular frustum: Horizontal, Vertical,
  44 //!                            LeftLower, RightLower,
  45 //!                            LeftUpper, RightUpper;
  46 //! - for triangular frustum: V0_Near - V0_Far, V1_Near - V1_Far, V2_Near - V2_Far,
  47 //!                           V1_Near - V0_Near, V2_Near - V1_Near, V2_Near - V0_Near.
  48 template <int N>
  49 class SelectMgr_Frustum : public SelectMgr_BaseFrustum
  50 {
  51 public:
  52
  53   SelectMgr_Frustum() : SelectMgr_BaseFrustum()
  54   {
  55     memset (myMaxOrthoVertsProjections, 0, sizeof (myMaxOrthoVertsProjections));
  56     memset (myMinOrthoVertsProjections, 0, sizeof (myMinOrthoVertsProjections));
  57     memset (myMaxVertsProjections, 0, sizeof (myMaxVertsProjections));
  58     memset (myMinVertsProjections, 0, sizeof (myMinVertsProjections));
  59   }
  60
  61   //! Dumps the content of me into the stream
  62   Standard_EXPORT virtual void DumpJson (Standard_OStream& theOStream, Standard_Integer theDepth = -1) const Standard_OVERRIDE;
  63
  64 protected:
  65
  66   // SAT Tests for different objects
  67
  68   //! Returns true if selecting volume is overlapped by axis-aligned bounding box
  69   //! with minimum corner at point theMinPt and maximum at point theMaxPt
  70   Standard_Boolean hasBoxOverlap (const SelectMgr_Vec3& theBoxMin,
  71                                   const SelectMgr_Vec3& theBoxMax,
  72                                   Standard_Boolean*     theInside = NULL) const;
  73
  74   //! SAT intersection test between defined volume and given point
  75   Standard_Boolean hasPointOverlap (const gp_Pnt& thePnt) const;
  76
  77   //! SAT intersection test between defined volume and given segment
  78   Standard_Boolean hasSegmentOverlap (const gp_Pnt& thePnt1,
  79                                       const gp_Pnt& thePnt2) const;
  80
  81   //! SAT intersection test between frustum given and planar convex polygon represented as ordered point set
  82   Standard_Boolean hasPolygonOverlap (const TColgp_Array1OfPnt& theArrayOfPnts,
  83                                       gp_Vec& theNormal) const;
  84
  85   //! SAT intersection test between defined volume and given triangle
  86   Standard_Boolean hasTriangleOverlap (const gp_Pnt& thePnt1,
  87                                        const gp_Pnt& thePnt2,
  88                                        const gp_Pnt& thePnt3,
  89                                        gp_Vec& theNormal) const;
  90
  91   //! Intersection test between defined volume and given sphere
  92   Standard_Boolean hasSphereOverlap (const gp_Pnt& thePnt1,
  93                                      const Standard_Real theRadius,
  94                                      Standard_Boolean* theInside = NULL) const;
  95
  96   //! Intersection test between defined volume and given cylinder (or cone).
  97   Standard_Boolean hasCylinderOverlap (const Standard_Real theBottomRad,
  98                                        const Standard_Real theTopRad,
  99                                        const Standard_Real theHeight,
 100                                        const gp_Trsf& theTrsf,
 101                                        Standard_Boolean* theInside = NULL) const;
 102
 103   //! Checking whether the point thePnt is inside the shape with borders theVertices.
 104   //! thePnt and theVertices lie in the same plane.
 105   Standard_Boolean IsDotInside (const gp_Pnt& thePnt,
 106                                 const TColgp_Array1OfPnt& theVertices) const;
 107
 108 private:
 109
 110   //! Return true if one segment enclosed between the points thePnt1Seg1 and thePnt2Seg1
 111   //! intersects another segment that enclosed between thePnt1Seg2 and thePnt2Seg2.
 112   Standard_Boolean isSegmentsIntersect (const gp_Pnt& thePnt1Seg1,
 113                                         const gp_Pnt& thePnt2Seg1,
 114                                         const gp_Pnt& thePnt1Seg2,
 115                                         const gp_Pnt& thePnt2Seg2) const;
 116
 117   //! Checking whether the borders theVertices of the shape intersect
 118   //! the cylinder (or cone) end face with the center theCenter and radius theRadius
 119   Standard_Boolean isIntersectCylinderEndFace (const Standard_Real theRad,
 120                                                const gp_Pnt& theCenter,
 121                                                const gp_Trsf& theTrsf,
 122                                                const TColgp_Array1OfPnt& theVertices) const;
 123
 124   //! Checks if AABB and frustum are separated along the given axis
 125   Standard_Boolean isSeparated (const SelectMgr_Vec3& theBoxMin,
 126                                 const SelectMgr_Vec3& theBoxMax,
 127                                 const gp_XYZ&         theDirect,
 128                                 Standard_Boolean*     theInside) const;
 129
 130   //! Checks if triangle and frustum are separated along the given axis
 131   Standard_Boolean isSeparated (const gp_Pnt& thePnt1,
 132                                 const gp_Pnt& thePnt2,
 133                                 const gp_Pnt& thePnt3,
 134                                 const gp_XYZ& theAxis) const;
 135
 136 protected:
 137
 138   gp_Vec myPlanes[N + 2];        //!< Plane equations
 139   gp_Pnt myVertices[N * 2];      //!< Vertices coordinates
 140
 141   Standard_Real myMaxVertsProjections[N + 2];      //!< Cached projections of vertices onto frustum plane directions
 142   Standard_Real myMinVertsProjections[N + 2];      //!< Cached projections of vertices onto frustum plane directions
 143   Standard_Real myMaxOrthoVertsProjections[3];     //!< Cached projections of vertices onto directions of ortho unit vectors
 144   Standard_Real myMinOrthoVertsProjections[3];     //!< Cached projections of vertices onto directions of ortho unit vectors
 145
 146   gp_Vec myEdgeDirs[6];                    //!< Cached edge directions
 147 };
 148
 149 #include <SelectMgr_Frustum.lxx>
 150
 151 #endif // _SelectMgr_Frustum_HeaderFile