CreateFromRotationMatrix() [1/2]

static Quaternion Microsoft.Xna.Framework.Quaternion.CreateFromRotationMatrix ( Matrix matrix )

inlinestatic

Definition at line 225 of file Quaternion.cs.

    {
        float num = matrix.M11 + matrix.M22 + matrix.M33;
        Quaternion result = default(Quaternion);
        if (num > 0f)
        {
            float num2 = (float)Math.Sqrt(num + 1f);
            result.W = num2 * 0.5f;
            num2 = 0.5f / num2;
            result.X = (matrix.M23 - matrix.M32) * num2;
            result.Y = (matrix.M31 - matrix.M13) * num2;
            result.Z = (matrix.M12 - matrix.M21) * num2;
        }
        else if (matrix.M11 >= matrix.M22 && matrix.M11 >= matrix.M33)
        {
            float num3 = (float)Math.Sqrt(1f + matrix.M11 - matrix.M22 - matrix.M33);
            float num4 = 0.5f / num3;
            result.X = 0.5f * num3;
            result.Y = (matrix.M12 + matrix.M21) * num4;
            result.Z = (matrix.M13 + matrix.M31) * num4;
            result.W = (matrix.M23 - matrix.M32) * num4;
        }
        else if (matrix.M22 > matrix.M33)
        {
            float num5 = (float)Math.Sqrt(1f + matrix.M22 - matrix.M11 - matrix.M33);
            float num6 = 0.5f / num5;
            result.X = (matrix.M21 + matrix.M12) * num6;
            result.Y = 0.5f * num5;
            result.Z = (matrix.M32 + matrix.M23) * num6;
            result.W = (matrix.M31 - matrix.M13) * num6;
        }
        else
        {
            float num7 = (float)Math.Sqrt(1f + matrix.M33 - matrix.M11 - matrix.M22);
            float num8 = 0.5f / num7;
            result.X = (matrix.M31 + matrix.M13) * num8;
            result.Y = (matrix.M32 + matrix.M23) * num8;
            result.Z = 0.5f * num7;
            result.W = (matrix.M12 - matrix.M21) * num8;
        }
        return result;
    }

References Microsoft.Xna.Framework.Matrix.M11, Microsoft.Xna.Framework.Matrix.M12, Microsoft.Xna.Framework.Matrix.M13, Microsoft.Xna.Framework.Matrix.M21, Microsoft.Xna.Framework.Matrix.M22, Microsoft.Xna.Framework.Matrix.M23, Microsoft.Xna.Framework.Matrix.M31, Microsoft.Xna.Framework.Matrix.M32, Microsoft.Xna.Framework.Matrix.M33, and System.Math.Sqrt().

Referenced by Microsoft.Xna.Framework.Matrix.Decompose().