LinearBlendSkinning.cpp

#include <Core/Animation/LinearBlendSkinning.hpp>
 
#include <Core/Animation/SkinningData.hpp>
 
namespace Ra {
namespace Core {
namespace Animation {
 
void linearBlendSkinning( const SkinningRefData& refData,
                          const Vector3Array& tangents,
                          const Vector3Array& bitangents,
                          SkinningFrameData& frameData ) {
    const auto& W          = refData.m_weights;
    const auto& vertices   = refData.m_referenceMesh.vertices();
    const auto& normals    = refData.m_referenceMesh.normals();
    const auto& bindMatrix = refData.m_bindMatrices;
    const auto& pose       = frameData.m_skeleton.getPose( HandleArray::SpaceType::MODEL );
#pragma omp parallel for
    for ( int i = 0; i < int( frameData.m_currentPosition.size() ); ++i ) {
        frameData.m_currentPosition[i]  = Vector3::Zero();
        frameData.m_currentNormal[i]    = Vector3::Zero();
        frameData.m_currentTangent[i]   = Vector3::Zero();
        frameData.m_currentBitangent[i] = Vector3::Zero();
    }
    for ( int k = 0; k < W.outerSize(); ++k ) {
        const int nonZero = W.col( k ).nonZeros();
        WeightMatrix::InnerIterator it0( W, k );
#pragma omp parallel for
        for ( int nz = 0; nz < nonZero; ++nz ) {
            WeightMatrix::InnerIterator it = it0 + Eigen::Index( nz );
            const uint i                   = it.row();
            const uint j                   = it.col();
            const Scalar w                 = it.value();
            // prepare the pose w.r.t. the bind matrix and the mesh transform
            const Transform M = refData.m_meshTransformInverse * pose[j] * bindMatrix[j];
            // apply LBS
            frameData.m_currentPosition[i] += w * ( M * vertices[i] );
            frameData.m_currentNormal[i] += w * ( M.linear() * normals[i] );
            frameData.m_currentTangent[i] += w * ( M.linear() * tangents[i] );
            frameData.m_currentBitangent[i] += w * ( M.linear() * bitangents[i] );
        }
    }
}
 
} // namespace Animation
} // namespace Core
} // namespace Ra