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Documentation                       Search   edge_collide.h Go to the documentation of this file. /* Copyright, 2001 Nevrax Ltd. * * This file is part of NEVRAX NEL. * NEVRAX NEL is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation; either version 2, or (at your option) * any later version. * NEVRAX NEL is distributed in the hope that it will be useful, but * WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU * General Public License for more details. * You should have received a copy of the GNU General Public License * along with NEVRAX NEL; see the file COPYING. If not, write to the * Free Software Foundation, Inc., 59 Temple Place - Suite 330, Boston, * MA 02111-1307, USA. */ #ifndef NL_EDGE_COLLIDE_H #define NL_EDGE_COLLIDE_H #include "nel/misc/types_nl.h" #include "nel/misc/vector_2f.h" namespace NLPACS { using NLMISC::CVector2f; // *************************************************************************** class CInt128 { public: sint64 High; sint64 Low; public: void setMul(sint64 a, sint64 b) { // reset and backup sign. sint sgn=0; if(a<0) sgn++, a=-a; if(b<0) sgn--, b=-b; // compute unsigned version. uint64 high, low, hl1, hl2, oldLow; uint32 mask32= 0xFFFFFFFF; high= (a>>32) * (b>>32); low= (a&mask32) * (b&mask32); hl1= (a&mask32) * (b>>32); hl2= (a>>32) * (b&mask32); // add/adc hl1. oldLow= low; low+= (hl1&mask32) << 32; if(low<oldLow) high++; high+= (hl1>>32); // add/adc hl2. oldLow= low; low+= (hl2&mask32) << 32; if(low<oldLow) high++; high+= (hl2>>32); // extend with sign. High= high; Low= low; if(sgn!=0) { High= -High; Low= -Low; } } bool operator<(const CInt128 &o) const { if(High!=o.High) return High<o.High; else return Low<o.Low; } bool operator==(const CInt128 &o) const { return High==o.High && Low==o.Low; } }; // *************************************************************************** class CRational64 { public: sint64 Numerator; sint64 Denominator; public: CRational64() {} CRational64(sint64 a) : Numerator(a), Denominator(1) {} CRational64(sint64 num, sint64 den) { if(den>0) { Numerator= num; Denominator= den; } else { Numerator= -num; Denominator= -den; } } bool operator<(const CRational64 &o) const { CInt128 n0, n1; // a/b < c/d <=> a*d < c*b n0.setMul(Numerator, o.Denominator); n1.setMul(o.Numerator, Denominator); return n0<n1; } bool operator==(const CRational64 &o) const { CInt128 n0, n1; // a/b == c/d <=> a*d == c*b n0.setMul(Numerator, o.Denominator); n1.setMul(o.Numerator, Denominator); return n0==n1; } }; // *************************************************************************** class CEdgeCollide { public: enum TPointMoveProblem {ParallelEdges=0, StartOnEdge, StopOnEdge, TraverseEndPoint, EdgeNull, PointMoveProblemCount}; public: CVector2f P0; CVector2f P1; CVector2f Dir, Norm; float A0, A1; float C; public: void make(const CVector2f &p0, const CVector2f &p1); CRational64 testPointMove(const CVector2f &start, const CVector2f &end, TPointMoveProblem &moveBug); float testCircleMove(const CVector2f &start, const CVector2f &delta, float radius, CVector2f &normal); float testBBoxMove(const CVector2f &start, const CVector2f &delta, const CVector2f bbox[4], CVector2f &normal); bool testBBoxCollide(const CVector2f bbox[4]); // **************************** private: bool testEdgeMove(const CVector2f &q0, const CVector2f &q1, const CVector2f &delta, float &tMin, float &tMax, bool &normalOnBox); }; } // NLPACS #endif // NL_EDGE_COLLIDE_H /* End of edge_collide.h */