/// <summary> Performs SVD on this matrix and gets scale and rotation.
/// Rotation is placed into rot.
/// </summary>
/// <param name="rot3">the rotation factor(Matrix3d).
/// </param>
/// <param name="rot4">the rotation factor(Matrix4f) only upper 3x3 elements are changed.
/// </param>
/// <returns> scale factor
/// </returns>
private float SVD(Matrix3f rot3, Matrix4f rot4)
{
// this is a simple svd.
// Not complete but fast and reasonable.
// See comment in Matrix3d.
//UPGRADE_WARNING: Data types in Visual C# might be different. Verify the accuracy of narrowing conversions. "ms-help://MS.VSCC.v80/dv_commoner/local/redirect.htm?index='!DefaultContextWindowIndex'&keyword='jlca1042'"
float s = (float) System.Math.Sqrt((m00 * m00 + m10 * m10 + m20 * m20 + m01 * m01 + m11 * m11 + m21 * m21 + m02 * m02 + m12 * m12 + m22 * m22) / 3.0);
// zero-div may occur.
float t = (s == 0.0f?0.0f:1.0f / s);
if (rot3 != null)
{
this.getRotationScale(rot3);
rot3.mul(t);
}
if (rot4 != null)
{
if (rot4 != this)
rot4.setRotationScale(this); // private method
rot4.mulRotationScale(t); // private method
}
return s;
}
/// <summary> Performs SVD on this matrix and gets the scale and the pure rotation.
/// The pure rotation is placed into rot.
/// </summary>
/// <param name="rot">the rotation factor.
/// </param>
/// <returns> scale factor
/// </returns>
private float SVD(Matrix3f rot)
{
// this is a simple svd.
// Not complete but fast and reasonable.
// See comment in Matrix3d.
double s = System.Math.Sqrt((m00 * m00 + m10 * m10 + m20 * m20 + m01 * m01 + m11 * m11 + m21 * m21 + m02 * m02 + m12 * m12 + m22 * m22) / 3.0);
// zero-div may occur.
double t = (s == 0.0?0.0:1.0 / s);
if (rot != null)
{
this.getRotationScale(rot);
//UPGRADE_WARNING: Data types in Visual C# might be different. Verify the accuracy of narrowing conversions. "ms-help://MS.VSCC.v80/dv_commoner/local/redirect.htm?index='!DefaultContextWindowIndex'&keyword='jlca1042'"
rot.mul((float) t);
}
//UPGRADE_WARNING: Data types in Visual C# might be different. Verify the accuracy of narrowing conversions. "ms-help://MS.VSCC.v80/dv_commoner/local/redirect.htm?index='!DefaultContextWindowIndex'&keyword='jlca1042'"
return (float) s;
}
