protected virtual void _updateFrustumPlanes()
{
// -------------------------
// Update the frustum planes
// -------------------------
Matrix4 combo = _projectionMatrix * _viewMatrix;
_planes[ (int)FrustumPlane.Left ].Normal.x = combo[ 3, 0 ] + combo[ 0, 0 ];
_planes[ (int)FrustumPlane.Left ].Normal.y = combo[ 3, 1 ] + combo[ 0, 1 ];
_planes[ (int)FrustumPlane.Left ].Normal.z = combo[ 3, 2 ] + combo[ 0, 2 ];
_planes[ (int)FrustumPlane.Left ].D = combo[ 3, 3 ] + combo[ 0, 3 ];
_planes[ (int)FrustumPlane.Right ].Normal.x = combo[ 3, 0 ] - combo[ 0, 0 ];
_planes[ (int)FrustumPlane.Right ].Normal.y = combo[ 3, 1 ] - combo[ 0, 1 ];
_planes[ (int)FrustumPlane.Right ].Normal.z = combo[ 3, 2 ] - combo[ 0, 2 ];
_planes[ (int)FrustumPlane.Right ].D = combo[ 3, 3 ] - combo[ 0, 3 ];
_planes[ (int)FrustumPlane.Top ].Normal.x = combo[ 3, 0 ] - combo[ 1, 0 ];
_planes[ (int)FrustumPlane.Top ].Normal.y = combo[ 3, 1 ] - combo[ 1, 1 ];
_planes[ (int)FrustumPlane.Top ].Normal.z = combo[ 3, 2 ] - combo[ 1, 2 ];
_planes[ (int)FrustumPlane.Top ].D = combo[ 3, 3 ] - combo[ 1, 3 ];
_planes[ (int)FrustumPlane.Bottom ].Normal.x = combo[ 3, 0 ] + combo[ 1, 0 ];
_planes[ (int)FrustumPlane.Bottom ].Normal.y = combo[ 3, 1 ] + combo[ 1, 1 ];
_planes[ (int)FrustumPlane.Bottom ].Normal.z = combo[ 3, 2 ] + combo[ 1, 2 ];
_planes[ (int)FrustumPlane.Bottom ].D = combo[ 3, 3 ] + combo[ 1, 3 ];
_planes[ (int)FrustumPlane.Near ].Normal.x = combo[ 3, 0 ] + combo[ 2, 0 ];
_planes[ (int)FrustumPlane.Near ].Normal.y = combo[ 3, 1 ] + combo[ 2, 1 ];
_planes[ (int)FrustumPlane.Near ].Normal.z = combo[ 3, 2 ] + combo[ 2, 2 ];
_planes[ (int)FrustumPlane.Near ].D = combo[ 3, 3 ] + combo[ 2, 3 ];
_planes[ (int)FrustumPlane.Far ].Normal.x = combo[ 3, 0 ] - combo[ 2, 0 ];
_planes[ (int)FrustumPlane.Far ].Normal.y = combo[ 3, 1 ] - combo[ 2, 1 ];
_planes[ (int)FrustumPlane.Far ].Normal.z = combo[ 3, 2 ] - combo[ 2, 2 ];
_planes[ (int)FrustumPlane.Far ].D = combo[ 3, 3 ] - combo[ 2, 3 ];
// Renormalise any normals which were not unit length
for ( int i = 0; i < 6; i++ )
{
float length = _planes[ i ].Normal.Normalize();
_planes[ i ].D /= length;
}
_recalculateFrustumPlanes = false;
}
