SA.FullBodyIK._LimitXZ C# (CSharp) Method

		public static bool _LimitXZ(
			ref Vector3 dir,				// dirY
			float limiXMinus,				// X-
			float limiXPlus,				// X+
			float limiZMinus,				// Z-
			float limiZPlus )				// Z+
		{
			bool isXPlus = (dir.x >= 0.0f);
			bool isZPlus = (dir.z >= 0.0f);
			float xLimit = isXPlus ? limiXPlus : limiXMinus;
			float zLimit = isZPlus ? limiZPlus : limiZMinus;

			bool isLimited = false;
			if( xLimit <= IKEpsilon && zLimit <= IKEpsilon ) {
				Vector3 limitedDir = new Vector3( 0.0f, 1.0f, 0.0f );
				Vector3 temp = limitedDir - dir;
				if( Mathf.Abs( temp.x ) > IKEpsilon || Mathf.Abs( temp.y ) > IKEpsilon || Mathf.Abs( temp.z ) > IKEpsilon ) {
					dir = limitedDir;
					isLimited = true;
				}
			} else {
				float inv_xLimit = (xLimit >= IKEpsilon) ? (1.0f / xLimit) : 0.0f;
				float inv_zLimit = (zLimit >= IKEpsilon) ? (1.0f / zLimit) : 0.0f;
				float localX = dir.x * inv_xLimit;
				float localZ = dir.z * inv_zLimit;
				float localLen = SAFBIKSqrt( localX * localX + localZ * localZ + dir.y * dir.y );

				float inv_localLen = (localLen > IKEpsilon) ? (1.0f / localLen) : 0.0f;
				float nrm_localX = localX * inv_localLen; // Counts as sinTheta
				float nrm_localZ = localZ * inv_localLen; // Counts as cosTheta

				if( localLen > 1.0f ) { // Outer circle.
					if( !isLimited ) {
						isLimited = true;
						localX = nrm_localX;
						localZ = nrm_localZ;
					}
				}

				float worldX = isLimited ? (localX * xLimit) : dir.x;
				float worldZ = isLimited ? (localZ * zLimit) : dir.z;

				bool isInverse = (dir.y < 0.0f);

				if( isLimited ) {
					float limitSinSq = (worldX * worldX + worldZ * worldZ);
					float limitSin = SAFBIKSqrt( limitSinSq );
					float limitCos = SAFBIKSqrt( 1.0f - limitSin * limitSin );
					dir.x = worldX;
					dir.y = limitCos;
					dir.z = worldZ;
				} else if( isInverse ) {
					isLimited = true;
					dir.y = -dir.y;
				}
			}

			return isLimited;
		}