Examples with SVDecomposition3d maspack.matrix.SVDecomposition3d used on opensource projects

Example 1 with SVDecomposition3d

use of maspack.matrix.SVDecomposition3d in project artisynth_core by artisynth.

the class FemMuscleModel method computeAverageFiberDirection.

/**
 * Computes the average fiber direction in the vicinity of a point based on
 * the line segments contained in a PolylineMesh. Returns the number of
 * supporting line segments used for the calculation. If no segments were
 * found, the method returns 0 and the direction is undefined.
 *
 * @param dir returns the normalized direction
 * @param pos position at which direction should be computed
 * @param rad radius of influence within which polyline mesh segments are
 * considerd
 * @param mesh mesh containing line segments used to determine the direction
 * @return number of supporting line segment
 */
public static int computeAverageFiberDirection(Vector3d dir, Point3d pos, double rad, PolylineMesh mesh) {
    BVTree bvh = mesh.getBVTree();
    ArrayList<BVNode> nodes = new ArrayList<BVNode>();
    Matrix3d cov = new Matrix3d();
    SVDecomposition3d svd = new SVDecomposition3d();
    Vector3d tmp = new Vector3d();
    Matrix3d tmp2 = new Matrix3d();
    bvh.intersectSphere(nodes, pos, rad);
    dir.setZero();
    int nsegs = 0;
    // for computing sign of direction vector
    Vector3d segmentSum = new Vector3d();
    // System.out.println("p=[");
    for (BVNode n : nodes) {
        Boundable[] elements = n.getElements();
        for (int i = 0; i < elements.length; i++) {
            LineSegment seg = (LineSegment) elements[i];
            seg = getSegmentInsideSphere(seg, pos, rad);
            if (seg != null) {
                tmp.sub(seg.myVtx1.pnt, seg.myVtx0.pnt);
                if (tmp.norm() >= 1e-8 * rad) {
                    // System.out.println(seg.myVtx0.getPosition() + " " +
                    // seg.myVtx1.getPosition());
                    nsegs++;
                    // prepare to average directions using SVD
                    computeCov(tmp2, tmp);
                    cov.add(tmp2);
                    segmentSum.add(tmp);
                }
            }
        }
    }
    if (nsegs > 0) {
        // we are technically including both +/- directions, so
        // we have twice the number of points
        cov.scale(2.0 / (2.0 * nsegs - 1));
        try {
            svd.factor(cov);
        } catch (Exception e) {
        // System.err.println(e.getMessage());
        }
        // principal components
        tmp2 = svd.getU();
        tmp2.getColumn(0, dir);
        dir.normalize();
        // most line segments
        if (dir.dot(segmentSum) < 0) {
            dir.scale(-1);
        }
        return nsegs;
    } else {
        return 0;
    }
}

Example 2 with SVDecomposition3d

use of maspack.matrix.SVDecomposition3d in project artisynth_core by artisynth.

the class StiffnessWarper3d method computeRotation.

/**
 * Computes a corotated rotation based on the deformation gradient
 * @param F deformation gradient
 * @param P symmetric part of gradient after rotation
 */
protected void computeRotation(Matrix3d F, SymmetricMatrix3d P) {
    if (R == null) {
        R = new RotationMatrix3d();
    }
    SVDecomposition3d SVD = new SVDecomposition3d();
    SVD.polarDecomposition(R, P, F);
}

Example 3 with SVDecomposition3d

use of maspack.matrix.SVDecomposition3d in project artisynth_core by artisynth.

the class LinearMaterialBase method computeRotation.

protected RotationMatrix3d computeRotation(Matrix3d F, SymmetricMatrix3d P) {
    if (mySVD == null) {
        mySVD = new SVDecomposition3d();
    }
    RotationMatrix3d R = new RotationMatrix3d();
    mySVD.polarDecomposition(R, P, F);
    return R;
}

Example 4 with SVDecomposition3d

use of maspack.matrix.SVDecomposition3d in project artisynth_core by artisynth.

the class MFreeMuscleModel method computeAverageFiberDirection.

public static boolean computeAverageFiberDirection(Vector3d dir, Point3d pos, double rad, PolylineMesh mesh) {
    BVTree bvh = mesh.getBVTree();
    ArrayList<BVNode> nodes = new ArrayList<BVNode>();
    Matrix3d cov = new Matrix3d();
    SVDecomposition3d svd = new SVDecomposition3d();
    Vector3d tmp = new Vector3d();
    Matrix3d tmp2 = new Matrix3d();
    bvh.intersectSphere(nodes, pos, rad);
    dir.setZero();
    int nsegs = 0;
    // for computing sign of direction vector
    Vector3d segmentSum = new Vector3d();
    // System.out.println("p=[");
    for (BVNode n : nodes) {
        Boundable[] elements = n.getElements();
        for (int i = 0; i < elements.length; i++) {
            LineSegment seg = (LineSegment) elements[i];
            seg = getSegmentInsideSphere(seg, pos, rad);
            if (seg != null) {
                tmp.sub(seg.myVtx1.pnt, seg.myVtx0.pnt);
                if (tmp.norm() >= 1e-8 * rad) {
                    // System.out.println(seg.myVtx0.getPosition() + " " +
                    // seg.myVtx1.getPosition());
                    nsegs++;
                    // prepare to average directions using SVD
                    computeCov(tmp2, tmp);
                    cov.add(tmp2);
                    segmentSum.add(tmp);
                }
            }
        }
    }
    if (nsegs > 0) {
        // we are technically including both +/- directions, so
        // we have twice the number of points
        cov.scale(2.0 / (2.0 * nsegs - 1));
        try {
            svd.factor(cov);
        } catch (Exception e) {
        // System.err.println(e.getMessage());
        }
        // principal components
        tmp2 = svd.getU();
        tmp2.getColumn(0, dir);
        dir.normalize();
        // most line segments
        if (dir.dot(segmentSum) < 0) {
            dir.scale(-1);
        }
        return true;
    } else {
        return false;
    }
}

Example 5 with SVDecomposition3d

use of maspack.matrix.SVDecomposition3d in project artisynth_core by artisynth.

the class MatricesUBO method updateMatrices.

public void updateMatrices(GL3 gl, Matrix4d proj, RigidTransform3d view, AffineTransform3dBase model, AffineTransform2dBase texture) {
    ByteBuffer buff = getBuffer();
    // model view
    AffineTransform3d modelview = new AffineTransform3d(view);
    modelview.mul(model);
    // pvm matrix
    buff.position(getByteOffset(PVM_IDX));
    mul(proj, modelview, buff);
    // model-view
    buff.position(getByteOffset(VM_IDX));
    putMatrix(buff, modelview);
    // model matrix
    buff.position(getByteOffset(M_IDX));
    putMatrix(buff, model);
    // normal
    buff.position(getByteOffset(NORMAL_IDX));
    if (model instanceof RigidTransform3d) {
        putMatrix(buff, modelview);
    } else {
        // invert model matrix
        Matrix3d A = new Matrix3d(model.getMatrix());
        if (!A.invert()) {
            // deal with non-invertible
            SVDecomposition3d svd3 = new SVDecomposition3d(model.getMatrix());
            svd3.pseudoInverse(A);
        }
        mulTranspose4x4(view.R, A, buff);
    }
    buff.position(getByteOffset(TEXTURE_IDX));
    putMatrix(buff, texture);
    buff.flip();
    update(gl, buff);
}