This is the asset I need to bake the lightmap for (the building in the centre):
is 10 meters long, 6 meters wide and 5 meters tall.
Every plank is a separate mesh and there are some details here and there, on the inside....
My issue is that, unless I set the lightmap resolution to a whopping 512px, I always get artefacts.
I've tried re-unwrapping this asset a number of times with a variety of padding values, but there's always some heavy bleeding, with lower resolutions.
This building, including its content, amounts to ~10.5k triangles. Mostly large ones from planks and beams.
I've read a fair amount of articles and forum posts (mostly old or about simple assets), on this subject, and it seems there are only two possible ways to handle lightmap UVs:
A.) you make UE4 or Blender unwrap the UVs automatically, tweaking padding/resolution through a trial and error procedure, or...
B.) you split UV faces manually wherever you have hard edges to avoid bleeding, giving more space to larger surfaces.
Now, this asset alone has over 6k faces, most of which have hard edges.
Do I really have to rearrange 6k faces manually?!
Isn't there some option C, for this poor peon? =(
Help, please! -.-'
Some tech notes:
. the three buildings together use a total of two materials, one tileable for the planks and beams and one atlas for everything else
. planks have no subdivisions and nearly all of them lack the smallest/hidden faces, so they're basically 8 triangles each
. the boat's skeleton cannot be removed from the building and placed as a secondary mesh, because it interacts with the rope, which interacts with the pulley, which interacts with the cart, which stands on wooden rails, which are connected to the rest of the building...or at least I wouldnt know how to do that without having serious issues repositioning the thing in the right spot....and even then, they wouldnt amount to more than about 2k-2.5k triangles, mostly small or insignificantly small surfaces