| /*! \file btGImpactMassUtil.h |
| \author Francisco Len Nßjera |
| */ |
| /* |
| This source file is part of GIMPACT Library. |
| |
| For the latest info, see http://gimpact.sourceforge.net/ |
| |
| Copyright (c) 2007 Francisco Leon Najera. C.C. 80087371. |
| email: projectileman@yahoo.com |
| |
| |
| 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. |
| */ |
| |
| |
| #ifndef GIMPACT_MASS_UTIL_H |
| #define GIMPACT_MASS_UTIL_H |
| |
| #include "LinearMath/btTransform.h" |
| |
| |
| |
| SIMD_FORCE_INLINE btVector3 gim_inertia_add_transformed( |
| const btVector3 & source_inertia, const btVector3 & added_inertia, const btTransform & transform) |
| { |
| btMatrix3x3 rotatedTensor = transform.getBasis().scaled(added_inertia) * transform.getBasis().transpose(); |
| |
| btScalar x2 = transform.getOrigin()[0]; |
| x2*= x2; |
| btScalar y2 = transform.getOrigin()[1]; |
| y2*= y2; |
| btScalar z2 = transform.getOrigin()[2]; |
| z2*= z2; |
| |
| btScalar ix = rotatedTensor[0][0]*(y2+z2); |
| btScalar iy = rotatedTensor[1][1]*(x2+z2); |
| btScalar iz = rotatedTensor[2][2]*(x2+y2); |
| |
| return btVector3(source_inertia[0]+ix,source_inertia[1]+iy,source_inertia[2] + iz); |
| } |
| |
| SIMD_FORCE_INLINE btVector3 gim_get_point_inertia(const btVector3 & point, btScalar mass) |
| { |
| btScalar x2 = point[0]*point[0]; |
| btScalar y2 = point[1]*point[1]; |
| btScalar z2 = point[2]*point[2]; |
| return btVector3(mass*(y2+z2),mass*(x2+z2),mass*(x2+y2)); |
| } |
| |
| |
| #endif //GIMPACT_MESH_SHAPE_H |