From 5e374328a87c1b418f8454d5ef38470484804961 Mon Sep 17 00:00:00 2001 From: Erwin Coumans Date: Sat, 12 Mar 2011 20:34:17 +0000 Subject: update Bullet physics sdk to latest trunk/version 2.78 add PhysicsConstraints.exportBulletFile(char* fileName) python command I'll be checking the bf-committers mailing list, in case this commit broke stuff scons needs to be updated, I'll do that in a second. --- .../CollisionShapes/btCylinderShape.cpp | 87 ++++++++++++++++++++-- 1 file changed, 80 insertions(+), 7 deletions(-) (limited to 'extern/bullet2/src/BulletCollision/CollisionShapes/btCylinderShape.cpp') diff --git a/extern/bullet2/src/BulletCollision/CollisionShapes/btCylinderShape.cpp b/extern/bullet2/src/BulletCollision/CollisionShapes/btCylinderShape.cpp index c9fa907edf3..c2e534b0b46 100644 --- a/extern/bullet2/src/BulletCollision/CollisionShapes/btCylinderShape.cpp +++ b/extern/bullet2/src/BulletCollision/CollisionShapes/btCylinderShape.cpp @@ -1,6 +1,6 @@ /* Bullet Continuous Collision Detection and Physics Library -Copyright (c) 2003-2006 Erwin Coumans http://continuousphysics.com/Bullet/ +Copyright (c) 2003-2009 Erwin Coumans http://bulletphysics.org 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. @@ -12,14 +12,16 @@ subject to the following restrictions: 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 "btCylinderShape.h" btCylinderShape::btCylinderShape (const btVector3& halfExtents) -:btBoxShape(halfExtents), +:btConvexInternalShape(), m_upAxis(1) { + btVector3 margin(getMargin(),getMargin(),getMargin()); + m_implicitShapeDimensions = (halfExtents * m_localScaling) - margin; m_shapeType = CYLINDER_SHAPE_PROXYTYPE; - recalcLocalAabb(); } @@ -27,7 +29,7 @@ btCylinderShapeX::btCylinderShapeX (const btVector3& halfExtents) :btCylinderShape(halfExtents) { m_upAxis = 0; - recalcLocalAabb(); + } @@ -35,13 +37,84 @@ btCylinderShapeZ::btCylinderShapeZ (const btVector3& halfExtents) :btCylinderShape(halfExtents) { m_upAxis = 2; - recalcLocalAabb(); + } void btCylinderShape::getAabb(const btTransform& t,btVector3& aabbMin,btVector3& aabbMax) const { - //skip the box 'getAabb' - btPolyhedralConvexShape::getAabb(t,aabbMin,aabbMax); + btTransformAabb(getHalfExtentsWithoutMargin(),getMargin(),t,aabbMin,aabbMax); +} + +void btCylinderShape::calculateLocalInertia(btScalar mass,btVector3& inertia) const +{ + +//Until Bullet 2.77 a box approximation was used, so uncomment this if you need backwards compatibility +//#define USE_BOX_INERTIA_APPROXIMATION 1 +#ifndef USE_BOX_INERTIA_APPROXIMATION + + /* + cylinder is defined as following: + * + * - principle axis aligned along y by default, radius in x, z-value not used + * - for btCylinderShapeX: principle axis aligned along x, radius in y direction, z-value not used + * - for btCylinderShapeZ: principle axis aligned along z, radius in x direction, y-value not used + * + */ + + btScalar radius2; // square of cylinder radius + btScalar height2; // square of cylinder height + btVector3 halfExtents = getHalfExtentsWithMargin(); // get cylinder dimension + btScalar div12 = mass / 12.f; + btScalar div4 = mass / 4.f; + btScalar div2 = mass / 2.f; + int idxRadius, idxHeight; + + switch (m_upAxis) // get indices of radius and height of cylinder + { + case 0: // cylinder is aligned along x + idxRadius = 1; + idxHeight = 0; + break; + case 2: // cylinder is aligned along z + idxRadius = 0; + idxHeight = 2; + break; + default: // cylinder is aligned along y + idxRadius = 0; + idxHeight = 1; + } + + // calculate squares + radius2 = halfExtents[idxRadius] * halfExtents[idxRadius]; + height2 = btScalar(4.) * halfExtents[idxHeight] * halfExtents[idxHeight]; + + // calculate tensor terms + btScalar t1 = div12 * height2 + div4 * radius2; + btScalar t2 = div2 * radius2; + + switch (m_upAxis) // set diagonal elements of inertia tensor + { + case 0: // cylinder is aligned along x + inertia.setValue(t2,t1,t1); + break; + case 2: // cylinder is aligned along z + inertia.setValue(t1,t1,t2); + break; + default: // cylinder is aligned along y + inertia.setValue(t1,t2,t1); + } +#else //USE_BOX_INERTIA_APPROXIMATION + //approximation of box shape + btVector3 halfExtents = getHalfExtentsWithMargin(); + + btScalar lx=btScalar(2.)*(halfExtents.x()); + btScalar ly=btScalar(2.)*(halfExtents.y()); + btScalar lz=btScalar(2.)*(halfExtents.z()); + + inertia.setValue(mass/(btScalar(12.0)) * (ly*ly + lz*lz), + mass/(btScalar(12.0)) * (lx*lx + lz*lz), + mass/(btScalar(12.0)) * (lx*lx + ly*ly)); +#endif //USE_BOX_INERTIA_APPROXIMATION } -- cgit v1.2.3