Method transformGeometry

src/Mod/Mesh/App/MeshProperties.cpp:188–218

}

void PropertyNormalList::transformGeometry(const Base::Matrix4D& mat)
{
    // A normal vector is only a direction with unit length, so we only need to rotate it
    // (no translations or scaling)

    // Extract scale factors (assumes an orthogonal rotation matrix)
    // Use the fact that the length of the row vectors of R are all equal to 1
    // And that scaling is applied after rotating
    double s[3];
    s[0] = sqrt(mat[0][0] * mat[0][0] + mat[0][1] * mat[0][1] + mat[0][2] * mat[0][2]);
    s[1] = sqrt(mat[1][0] * mat[1][0] + mat[1][1] * mat[1][1] + mat[1][2] * mat[1][2]);
    s[2] = sqrt(mat[2][0] * mat[2][0] + mat[2][1] * mat[2][1] + mat[2][2] * mat[2][2]);

    // Set up the rotation matrix: zero the translations and make the scale factors = 1
    Base::Matrix4D rot;
    rot.setToUnity();
    for (unsigned short i = 0; i < 3; i++) {
        for (unsigned short j = 0; j < 3; j++) {
            rot[i][j] = mat[i][j] / s[i];
        }
    }

    aboutToSetValue();

    // Rotate the normal vectors
    for (int ii = 0; ii < getSize(); ii++) {
        set1Value(ii, rot * operator[](ii));
    }

    hasSetValue();
}

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