mirror of
https://github.com/Relintai/pandemonium_engine.git
synced 2024-12-23 12:26:59 +01:00
76 lines
2.9 KiB
C++
76 lines
2.9 KiB
C++
#ifndef _BT_LCP_H_
|
|
#define _BT_LCP_H_
|
|
/*************************************************************************
|
|
* *
|
|
* Open Dynamics Engine, Copyright (C) 2001,2002 Russell L. Smith. *
|
|
* All rights reserved. Email: russ@q12.org Web: www.q12.org *
|
|
* *
|
|
* This library is free software; you can redistribute it and/or *
|
|
* modify it under the terms of *
|
|
* The BSD-style license that is included with this library in *
|
|
* the file LICENSE-BSD.TXT. *
|
|
* *
|
|
* This library 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 files *
|
|
* LICENSE.TXT and LICENSE-BSD.TXT for more details. *
|
|
* *
|
|
*************************************************************************/
|
|
|
|
/*
|
|
|
|
given (A,b,lo,hi), solve the LCP problem: A*x = b+w, where each x(i),w(i)
|
|
satisfies one of
|
|
(1) x = lo, w >= 0
|
|
(2) x = hi, w <= 0
|
|
(3) lo < x < hi, w = 0
|
|
A is a matrix of dimension n*n, everything else is a vector of size n*1.
|
|
lo and hi can be +/- dInfinity as needed. the first `nub' variables are
|
|
unbounded, i.e. hi and lo are assumed to be +/- dInfinity.
|
|
|
|
we restrict lo(i) <= 0 and hi(i) >= 0.
|
|
|
|
the original data (A,b) may be modified by this function.
|
|
|
|
if the `findex' (friction index) parameter is nonzero, it points to an array
|
|
of index values. in this case constraints that have findex[i] >= 0 are
|
|
special. all non-special constraints are solved for, then the lo and hi values
|
|
for the special constraints are set:
|
|
hi[i] = abs( hi[i] * x[findex[i]] )
|
|
lo[i] = -hi[i]
|
|
and the solution continues. this mechanism allows a friction approximation
|
|
to be implemented. the first `nub' variables are assumed to have findex < 0.
|
|
|
|
*/
|
|
|
|
|
|
|
|
|
|
#include <stdlib.h>
|
|
#include <stdio.h>
|
|
#include <assert.h>
|
|
|
|
#include "LinearMath/btScalar.h"
|
|
#include "LinearMath/btAlignedObjectArray.h"
|
|
|
|
struct btDantzigScratchMemory
|
|
{
|
|
btAlignedObjectArray<btScalar> m_scratch;
|
|
btAlignedObjectArray<btScalar> L;
|
|
btAlignedObjectArray<btScalar> d;
|
|
btAlignedObjectArray<btScalar> delta_w;
|
|
btAlignedObjectArray<btScalar> delta_x;
|
|
btAlignedObjectArray<btScalar> Dell;
|
|
btAlignedObjectArray<btScalar> ell;
|
|
btAlignedObjectArray<btScalar *> Arows;
|
|
btAlignedObjectArray<int> p;
|
|
btAlignedObjectArray<int> C;
|
|
btAlignedObjectArray<bool> state;
|
|
};
|
|
|
|
//return false if solving failed
|
|
bool btSolveDantzigLCP(int n, btScalar *A, btScalar *x, btScalar *b, btScalar *w,
|
|
int nub, btScalar *lo, btScalar *hi, int *findex, btDantzigScratchMemory &scratch);
|
|
|
|
#endif //_BT_LCP_H_
|