Distorted Android

///////////////////////////////////////////////////////////////////////////////////////////////////

// ret = (qx,qy,qz,qw)*(rx,ry,rz,rw)

  public static void quatMultiply( float[] ret, Static4D q, float[] r )

    {

    float q0 = q.get0();

    float q1 = q.get1();

    float q2 = q.get2();

    float q3 = q.get3();

    ret[0] = r[3]*q0 - r[2]*q1 + r[1]*q2 + r[0]*q3;

    ret[1] = r[3]*q1 + r[2]*q0 + r[1]*q3 - r[0]*q2;

    ret[2] = r[3]*q2 + r[2]*q3 - r[1]*q0 + r[0]*q1;

    ret[3] = r[3]*q3 - r[2]*q2 - r[1]*q1 - r[0]*q0;

    }

///////////////////////////////////////////////////////////////////////////////////////////////////

// ret = (qx,qy,qz,qw)*(rx,ry,rz,rw)

  public static void quatMultiply( float[] ret, float[] q, Static4D r )

    {

    float r0 = r.get0();

    float r1 = r.get1();

    float r2 = r.get2();

    float r3 = r.get3();

    ret[0] = r3*q[0] - r2*q[1] + r1*q[2] + r0*q[3];

    ret[1] = r3*q[1] + r2*q[0] + r1*q[3] - r0*q[2];

    ret[2] = r3*q[2] + r2*q[3] - r1*q[0] + r0*q[1];

    ret[3] = r3*q[3] - r2*q[2] - r1*q[1] - r0*q[0];

    }

///////////////////////////////////////////////////////////////////////////////////////////////////

// rotate vec by quat ( i.e. return quat*vector*(quat^-1) )

  public static void rotateVectorByQuat(float[] output, float[] vec, Static4D quat)

    {

    float[] tmp = new float[4];

    quatMultiply(tmp,quat,vec);

    float x1 = quat.get0();

    float y1 = quat.get1();

    float z1 = quat.get2();

    float w1 = quat.get3();

    quat.set(-x1,-y1,-z1,w1);

    quatMultiply(output,tmp,quat);

    float x2 = quat.get0();

    float y2 = quat.get1();

    float z2 = quat.get2();

    float w2 = quat.get3();

    quat.set(-x2,-y2,-z2,w2);

    }

///////////////////////////////////////////////////////////////////////////////////////////////////

// rotate 'vector' by quat^(-1)  ( i.e. return (quat^-1)*vector*quat )

  public static void rotateVectorByInvertedQuat(float[] output, float x, float y, float z, float w, Static4D quat)

    {

    float[] tmp = new float[4];

    float qx = quat.get0();

    float qy = quat.get1();

    float qz = quat.get2();

    float qw = quat.get3();

    quatMultiply(tmp,-qx,-qy,-qz,qw,x,y,z,w);

    quatMultiply(output,tmp[0],tmp[1],tmp[2],tmp[3],qx,qy,qz,qw);

    }