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authorRémi Verschelde <rverschelde@gmail.com>2018-01-13 14:01:53 +0100
committerRémi Verschelde <rverschelde@gmail.com>2018-01-13 14:08:45 +0100
commite12c89e8c9896b2e5cdd70dbd2d2acb449ff4b94 (patch)
treeaf68e434545e20c538f896e28b73f2db7d626edd /thirdparty/bullet/BulletDynamics/MLCPSolvers/btLemkeAlgorithm.h
parent53c65ae7619ac9e80c89a321c70de64f3745e2aa (diff)
bullet: Streamline bundling, remove extraneous src/ folder
Document version and how to extract sources in thirdparty/README.md. Drop unnecessary CMake and Premake files. Simplify SCsub, drop unused one.
Diffstat (limited to 'thirdparty/bullet/BulletDynamics/MLCPSolvers/btLemkeAlgorithm.h')
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diff --git a/thirdparty/bullet/BulletDynamics/MLCPSolvers/btLemkeAlgorithm.h b/thirdparty/bullet/BulletDynamics/MLCPSolvers/btLemkeAlgorithm.h
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+/* Copyright (C) 2004-2013 MBSim Development Team
+
+Code was converted for the Bullet Continuous Collision Detection and Physics Library
+
+This software is provided 'as-is', without any express or implied warranty.
+In no event will the authors be held liable for any damages arising from the use of this software.
+Permission is granted to anyone to use this software for any purpose,
+including commercial applications, and to alter it and redistribute it freely,
+subject to the following restrictions:
+
+1. The origin of this software must not be misrepresented; you must not claim that you wrote the original software. If you use this software in a product, an acknowledgment in the product documentation would be appreciated but is not required.
+2. Altered source versions must be plainly marked as such, and must not be misrepresented as being the original software.
+3. This notice may not be removed or altered from any source distribution.
+*/
+
+//The original version is here
+//https://code.google.com/p/mbsim-env/source/browse/trunk/kernel/mbsim/numerics/linear_complementarity_problem/lemke_algorithm.cc
+//This file is re-distributed under the ZLib license, with permission of the original author (Kilian Grundl)
+//Math library was replaced from fmatvec to a the file src/LinearMath/btMatrixX.h
+//STL/std::vector replaced by btAlignedObjectArray
+
+
+
+#ifndef BT_NUMERICS_LEMKE_ALGORITHM_H_
+#define BT_NUMERICS_LEMKE_ALGORITHM_H_
+
+#include "LinearMath/btMatrixX.h"
+
+
+#include <vector> //todo: replace by btAlignedObjectArray
+
+class btLemkeAlgorithm
+{
+public:
+
+
+ btLemkeAlgorithm(const btMatrixXu& M_, const btVectorXu& q_, const int & DEBUGLEVEL_ = 0) :
+ DEBUGLEVEL(DEBUGLEVEL_)
+ {
+ setSystem(M_, q_);
+ }
+
+ /* GETTER / SETTER */
+ /**
+ * \brief return info of solution process
+ */
+ int getInfo() {
+ return info;
+ }
+
+ /**
+ * \brief get the number of steps until the solution was found
+ */
+ int getSteps(void) {
+ return steps;
+ }
+
+
+
+ /**
+ * \brief set system with Matrix M and vector q
+ */
+ void setSystem(const btMatrixXu & M_, const btVectorXu & q_)
+ {
+ m_M = M_;
+ m_q = q_;
+ }
+ /***************************************************/
+
+ /**
+ * \brief solve algorithm adapted from : Fast Implementation of Lemke’s Algorithm for Rigid Body Contact Simulation (John E. Lloyd)
+ */
+ btVectorXu solve(unsigned int maxloops = 0);
+
+ virtual ~btLemkeAlgorithm() {
+ }
+
+protected:
+ int findLexicographicMinimum(const btMatrixXu &A, const int & pivotColIndex);
+ bool LexicographicPositive(const btVectorXu & v);
+ void GaussJordanEliminationStep(btMatrixXu &A, int pivotRowIndex, int pivotColumnIndex, const btAlignedObjectArray<int>& basis);
+ bool greaterZero(const btVectorXu & vector);
+ bool validBasis(const btAlignedObjectArray<int>& basis);
+
+ btMatrixXu m_M;
+ btVectorXu m_q;
+
+ /**
+ * \brief number of steps until the Lemke algorithm found a solution
+ */
+ unsigned int steps;
+
+ /**
+ * \brief define level of debug output
+ */
+ int DEBUGLEVEL;
+
+ /**
+ * \brief did the algorithm find a solution
+ *
+ * -1 : not successful
+ * 0 : successful
+ */
+ int info;
+};
+
+
+#endif /* BT_NUMERICS_LEMKE_ALGORITHM_H_ */