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-rw-r--r--thirdparty/bullet/src/LinearMath/btGeometryUtil.cpp185
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diff --git a/thirdparty/bullet/src/LinearMath/btGeometryUtil.cpp b/thirdparty/bullet/src/LinearMath/btGeometryUtil.cpp
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+/*
+Copyright (c) 2003-2006 Gino van den Bergen / 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 "btGeometryUtil.h"
+
+
+/*
+ Make sure this dummy function never changes so that it
+ can be used by probes that are checking whether the
+ library is actually installed.
+*/
+extern "C"
+{
+ void btBulletMathProbe ();
+
+ void btBulletMathProbe () {}
+}
+
+
+bool btGeometryUtil::isPointInsidePlanes(const btAlignedObjectArray<btVector3>& planeEquations, const btVector3& point, btScalar margin)
+{
+ int numbrushes = planeEquations.size();
+ for (int i=0;i<numbrushes;i++)
+ {
+ const btVector3& N1 = planeEquations[i];
+ btScalar dist = btScalar(N1.dot(point))+btScalar(N1[3])-margin;
+ if (dist>btScalar(0.))
+ {
+ return false;
+ }
+ }
+ return true;
+
+}
+
+
+bool btGeometryUtil::areVerticesBehindPlane(const btVector3& planeNormal, const btAlignedObjectArray<btVector3>& vertices, btScalar margin)
+{
+ int numvertices = vertices.size();
+ for (int i=0;i<numvertices;i++)
+ {
+ const btVector3& N1 = vertices[i];
+ btScalar dist = btScalar(planeNormal.dot(N1))+btScalar(planeNormal[3])-margin;
+ if (dist>btScalar(0.))
+ {
+ return false;
+ }
+ }
+ return true;
+}
+
+bool notExist(const btVector3& planeEquation,const btAlignedObjectArray<btVector3>& planeEquations);
+
+bool notExist(const btVector3& planeEquation,const btAlignedObjectArray<btVector3>& planeEquations)
+{
+ int numbrushes = planeEquations.size();
+ for (int i=0;i<numbrushes;i++)
+ {
+ const btVector3& N1 = planeEquations[i];
+ if (planeEquation.dot(N1) > btScalar(0.999))
+ {
+ return false;
+ }
+ }
+ return true;
+}
+
+void btGeometryUtil::getPlaneEquationsFromVertices(btAlignedObjectArray<btVector3>& vertices, btAlignedObjectArray<btVector3>& planeEquationsOut )
+{
+ const int numvertices = vertices.size();
+ // brute force:
+ for (int i=0;i<numvertices;i++)
+ {
+ const btVector3& N1 = vertices[i];
+
+
+ for (int j=i+1;j<numvertices;j++)
+ {
+ const btVector3& N2 = vertices[j];
+
+ for (int k=j+1;k<numvertices;k++)
+ {
+
+ const btVector3& N3 = vertices[k];
+
+ btVector3 planeEquation,edge0,edge1;
+ edge0 = N2-N1;
+ edge1 = N3-N1;
+ btScalar normalSign = btScalar(1.);
+ for (int ww=0;ww<2;ww++)
+ {
+ planeEquation = normalSign * edge0.cross(edge1);
+ if (planeEquation.length2() > btScalar(0.0001))
+ {
+ planeEquation.normalize();
+ if (notExist(planeEquation,planeEquationsOut))
+ {
+ planeEquation[3] = -planeEquation.dot(N1);
+
+ //check if inside, and replace supportingVertexOut if needed
+ if (areVerticesBehindPlane(planeEquation,vertices,btScalar(0.01)))
+ {
+ planeEquationsOut.push_back(planeEquation);
+ }
+ }
+ }
+ normalSign = btScalar(-1.);
+ }
+
+ }
+ }
+ }
+
+}
+
+void btGeometryUtil::getVerticesFromPlaneEquations(const btAlignedObjectArray<btVector3>& planeEquations , btAlignedObjectArray<btVector3>& verticesOut )
+{
+ const int numbrushes = planeEquations.size();
+ // brute force:
+ for (int i=0;i<numbrushes;i++)
+ {
+ const btVector3& N1 = planeEquations[i];
+
+
+ for (int j=i+1;j<numbrushes;j++)
+ {
+ const btVector3& N2 = planeEquations[j];
+
+ for (int k=j+1;k<numbrushes;k++)
+ {
+
+ const btVector3& N3 = planeEquations[k];
+
+ btVector3 n2n3; n2n3 = N2.cross(N3);
+ btVector3 n3n1; n3n1 = N3.cross(N1);
+ btVector3 n1n2; n1n2 = N1.cross(N2);
+
+ if ( ( n2n3.length2() > btScalar(0.0001) ) &&
+ ( n3n1.length2() > btScalar(0.0001) ) &&
+ ( n1n2.length2() > btScalar(0.0001) ) )
+ {
+ //point P out of 3 plane equations:
+
+ // d1 ( N2 * N3 ) + d2 ( N3 * N1 ) + d3 ( N1 * N2 )
+ //P = -------------------------------------------------------------------------
+ // N1 . ( N2 * N3 )
+
+
+ btScalar quotient = (N1.dot(n2n3));
+ if (btFabs(quotient) > btScalar(0.000001))
+ {
+ quotient = btScalar(-1.) / quotient;
+ n2n3 *= N1[3];
+ n3n1 *= N2[3];
+ n1n2 *= N3[3];
+ btVector3 potentialVertex = n2n3;
+ potentialVertex += n3n1;
+ potentialVertex += n1n2;
+ potentialVertex *= quotient;
+
+ //check if inside, and replace supportingVertexOut if needed
+ if (isPointInsidePlanes(planeEquations,potentialVertex,btScalar(0.01)))
+ {
+ verticesOut.push_back(potentialVertex);
+ }
+ }
+ }
+ }
+ }
+ }
+}
+