FLightMap2D::Serialize() contains a possible index out of range error.

A user pointed out a potential to have an index out of range error in the source code.

There are also a few magic numbers scattered around in this function.

1. Open the file LightMap.cpp
2. Find the function FLightMap2D::Serialize().

RESULT:
The if statement if( Ar.IsLoading() && Ar.UE4Ver() < VER_UE4_LOW_QUALITY_DIRECTIONAL_LIGHTMAPS ) contains a for loop that loops three times, but the Texture array contained in the loop only has two elements. On the third loop, the texture array may try to reference a non-existing element.

EXPECTED:
No out of range condition exists.