1 files changed, 160 insertions, 0 deletions
diff --git a/extern/bullet2/BulletCollision/NarrowPhaseCollision/btSubSimplexConvexCast.cpp b/extern/bullet2/BulletCollision/NarrowPhaseCollision/btSubSimplexConvexCast.cpp
new file mode 100644
index 00000000000..18eb662de2f
--- /dev/null
+++ b/extern/bullet2/BulletCollision/NarrowPhaseCollision/btSubSimplexConvexCast.cpp
@@ -0,0 +1,160 @@
+/*
+Bullet Continuous Collision Detection and Physics Library
+Copyright (c) 2003-2006 Erwin Coumans  http://continuousphysics.com/Bullet/
+
+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.
+*/
+
+
+#include "btSubSimplexConvexCast.h"
+#include "BulletCollision/CollisionShapes/btConvexShape.h"
+
+#include "BulletCollision/CollisionShapes/btMinkowskiSumShape.h"
+#include "BulletCollision/NarrowPhaseCollision/btSimplexSolverInterface.h"
+#include "btPointCollector.h"
+#include "LinearMath/btTransformUtil.h"
+
+btSubsimplexConvexCast::btSubsimplexConvexCast (const btConvexShape* convexA,const btConvexShape* convexB,btSimplexSolverInterface* simplexSolver)
+:m_simplexSolver(simplexSolver),
+m_convexA(convexA),m_convexB(convexB)
+{
+}
+
+///Typically the conservative advancement reaches solution in a few iterations, clip it to 32 for degenerate cases.
+///See discussion about this here http://continuousphysics.com/Bullet/phpBB2/viewtopic.php?t=565
+#ifdef BT_USE_DOUBLE_PRECISION
+#define MAX_ITERATIONS 64
+#else
+#define MAX_ITERATIONS 32
+#endif
+bool	btSubsimplexConvexCast::calcTimeOfImpact(
+		const btTransform& fromA,
+		const btTransform& toA,
+		const btTransform& fromB,
+		const btTransform& toB,
+		CastResult& result)
+{
+
+	m_simplexSolver->reset();
+
+	btVector3 linVelA,linVelB;
+	linVelA = toA.getOrigin()-fromA.getOrigin();
+	linVelB = toB.getOrigin()-fromB.getOrigin();
+
+	btScalar lambda = btScalar(0.);
+
+	btTransform interpolatedTransA = fromA;
+	btTransform interpolatedTransB = fromB;
+
+	///take relative motion
+	btVector3 r = (linVelA-linVelB);
+	btVector3 v;
+	
+	btVector3 supVertexA = fromA(m_convexA->localGetSupportingVertex(-r*fromA.getBasis()));
+	btVector3 supVertexB = fromB(m_convexB->localGetSupportingVertex(r*fromB.getBasis()));
+	v = supVertexA-supVertexB;
+	int maxIter = MAX_ITERATIONS;
+
+	btVector3 n;
+	n.setValue(btScalar(0.),btScalar(0.),btScalar(0.));
+	bool hasResult = false;
+	btVector3 c;
+
+	btScalar lastLambda = lambda;
+
+
+	btScalar dist2 = v.length2();
+#ifdef BT_USE_DOUBLE_PRECISION
+	btScalar epsilon = btScalar(0.0001);
+#else
+	btScalar epsilon = btScalar(0.0001);
+#endif //BT_USE_DOUBLE_PRECISION
+	btVector3	w,p;
+	btScalar VdotR;
+	
+	while ( (dist2 > epsilon) && maxIter--)
+	{
+		supVertexA = interpolatedTransA(m_convexA->localGetSupportingVertex(-v*interpolatedTransA.getBasis()));
+		supVertexB = interpolatedTransB(m_convexB->localGetSupportingVertex(v*interpolatedTransB.getBasis()));
+		w = supVertexA-supVertexB;
+
+		btScalar VdotW = v.dot(w);
+
+		if (lambda > btScalar(1.0))
+		{
+			return false;
+		}
+
+		if ( VdotW > btScalar(0.))
+		{
+			VdotR = v.dot(r);
+
+			if (VdotR >= -(SIMD_EPSILON*SIMD_EPSILON))
+				return false;
+			else
+			{
+				lambda = lambda - VdotW / VdotR;
+				//interpolate to next lambda
+				//	x = s + lambda * r;
+				interpolatedTransA.getOrigin().setInterpolate3(fromA.getOrigin(),toA.getOrigin(),lambda);
+				interpolatedTransB.getOrigin().setInterpolate3(fromB.getOrigin(),toB.getOrigin(),lambda);
+				//m_simplexSolver->reset();
+				//check next line
+				 w = supVertexA-supVertexB;
+				lastLambda = lambda;
+				n = v;
+				hasResult = true;
+			}
+		} 
+		///Just like regular GJK only add the vertex if it isn't already (close) to current vertex, it would lead to divisions by zero and NaN etc.
+		if (!m_simplexSolver->inSimplex(w))
+			m_simplexSolver->addVertex( w, supVertexA , supVertexB);
+
+		if (m_simplexSolver->closest(v))
+		{
+			dist2 = v.length2();
+			hasResult = true;
+			//todo: check this normal for validity
+			//n=v;
+			//printf("V=%f , %f, %f\n",v[0],v[1],v[2]);
+			//printf("DIST2=%f\n",dist2);
+			//printf("numverts = %i\n",m_simplexSolver->numVertices());
+		} else
+		{
+			dist2 = btScalar(0.);
+		} 
+	}
+
+	//int numiter = MAX_ITERATIONS - maxIter;
+//	printf("number of iterations: %d", numiter);
+	
+	//don't report a time of impact when moving 'away' from the hitnormal
+	
+
+	result.m_fraction = lambda;
+	if (n.length2() >= (SIMD_EPSILON*SIMD_EPSILON))
+		result.m_normal = n.normalized();
+	else
+		result.m_normal = btVector3(btScalar(0.0), btScalar(0.0), btScalar(0.0));
+
+	//don't report time of impact for motion away from the contact normal (or causes minor penetration)
+	if (result.m_normal.dot(r)>=-result.m_allowedPenetration)
+		return false;
+
+	btVector3 hitA,hitB;
+	m_simplexSolver->compute_points(hitA,hitB);
+	result.m_hitPoint=hitB;
+	return true;
+}
+
+
+
+