Tottally Black object after light rebuild etc.

I won’t do that sorry. It’s not a matter of you are trustworthy, is a matter of I have no idea if you are, or not, and I truly want to reigterate, I don’t mean that offensively!!

Im told my object is possibly too complex or something. The object is 148k with a very complex DENSE looking lighgtmap, but I choose islands setting of .008 in blender which should have been plenty Res was 1024, so maybe I should have chosen 2048 or higher ?

I had it suggested that I make normal map for it, but is that really going to preserve the detail I need for the mesh,given its a plot area ?

all ideas welcome


Thats true that 4.5 removes generate UV’s , but Tim tells me, that is because ( I really wish Ihad 4.5, as I think that would resolve my issue) importing a mesh now automatically is generating them for us, unless I misunderstood but I don’t think so, and yes I wish ue4 lightmap issues were resolved and soon as unity never had such issues, BUT we all knew getting into ue4 at this juncture that it would have hickups along the way tiil a certain stable version, given it notes the current status is meant for devvelopers, if I read it right or maybe that has subsequently been removed given its enhancements since then, dunno.

anyway maybe my 148K mesh and its huge lightgmap channel is just too much for engine atm ?

all ideas welcome.


148k polys is too much, if it includes a bunch of different level elements you need to separate the mesh into pieces, if it’s a single high detail mesh then you need to find another solution for getting the detail like normal maps.

Just wondering, someone suggested that I separate mesh into like 5 pieces which I did, but even though I select each one and export to files named 1 and last with 5, even bringing in just the mesh1.fbx, oddly enough brings in the entire 148mesh.

Any idea how I tell blender not to export them all when I just want piece 1 ?
EDIT this: Foundit: only selected in fbx export settings ! ( Haven’t tried this yet, decided to go for normal map route 1st!!! SEE BELOW )

EDIT 2<< : one last thing: I tried low res+NormapMap ( reduced mesh to 48k vs 148K so I thought this would finally fix things! but no lightmap still), see attached image for assisting me with why I still get: layoutUV failed, can’t generate a d3dxmesh.



When you get that error during the lightmap creation in the UE4, I would recommend you to create the lightmap in your 3d program, because as far as I know there is no real solution for that “d3dxmesh error” :slight_smile:

That mesh should not be more than like 1000 polys

If you’ve ever created a high res model , meant to be traversed on by the player with very good detail, then I’d find it real hard to believe
you got it down to 1K polys which is only 2k tris. I realize you can fudge with the normal map between high and low res, but there is no way on Earth you can make
up for that much detail with just a normal map, unless you have some secret formula ? :wink: I realize I don’t have the object textured yet or other objects added to overall level, but still 1k sees pretty
darn miserly :slight_smile: This is the key plot point in the game btw,so I can’t make it look like a blob of nothing.

I’d love to hear about it if you do. I mean I realize we all have to be careful what audience we are after and take into inconsideration their performance, but I mean newer rigs won’t have any problem with millions of verts right ?

Just going down 100K and I lost to much detail, though I can make it up by inserting a mesh to replace a plot item in game that was totally destroyed by the conversion.


FYI, I tried again and this time I got it to go in from blender, not sure what the diff was, but upon rebuilding lighting, it at least doesn’t have the crisscrossing lines, but its clear I need to change the unwrapping method or something, as the lighting is very strange in places,but it at least it works.

I"ll try to get a image posted later of before and after and hope somebody has an idea how I fix it ( if I dont’ first).


From that screenshot there’s just not anything there that requires much geometry, hardly even needs a normal map.

Just create one like it is shown here:

or take a look at this video (not the recommended way, but it should work ^^):

How exactly does it look like after you have rebuild the light?

Darthviper is right, 140k is a lot and it is even worse if the model is hard to unwrap the UV’s for lightmapping. You may want to consider retopologizing it, as suggested before(you can preserve the silhouette and have a smooth look with well arranged smoothing groups for 48k poly’s if you know how to retopo properly) or just make it a movable object. If you still insist then at least post a proper screenshot of your model please if you want more help.

I’ve known 140k is too much for a while now ( for in game anyway_), but thx anyway, and pls see proof below of the ‘detail’, I’m talking about. Ive checked retopo blender videos and Im not seeing much in the way of help on the topic\ but I’ll keep looking. 'As I say I tried shrinnkwrap which was useless, and normap map which didn’t seem to help either but I’ll keep trying with sculptris given the awesome reduce brush it has.


Are you scuplting everything within Blender, or do you have a separate program such as Mudbox or ZBrush?

Usually the meshes that come back from those programs (and even in blender’s sculpt tool) get sculpted at as high poly as possible to keep the details. To get the best results, you will want to create a somewhat lower poly mesh of the same model. Do not worry that some of the detail get’s lost, as you will be baking this information onto a normal map. Export out both the high and low poly versions of the mesh to a folder.

Do not worry about the detail being missing, we will now bake that info into the mesh. Download and install xNormal .

When it opens up click on the “High Poly” tab, and load your High poly mesh into the first slot. Now go to the Low Poly section, and choose your low poly mesh.

Next click on the Baking Options button, in the top box, you want to enter a folder to save all output to, also choose a size (2048x2048 should be enough). Now in the “Maps to Render” make sure ONLY Normal map is selected.

Now all you need to do is click Generate Maps button on the bottom right, this will output a normal map texture to the folder you specified. If you now import both the low poly and the normal map, and create a basic material. Make sure to plug your normal map into the normal slot, save the material and apply it to the mesh you imported.

This should give you an idea of how to keep details on the model surface while using the lowest number of tri’s possible.

Let me know if any of that doesn’t make sense, but I can assure that this will work with fewer poly’s (1k poly’s is a bit too low, as you get better at normal mapping it may be possible, but in this case even if we can cut the poly count in half, it will make a big difference.

Hope that helps, let me know if you need any assistance. :slight_smile:

Sculpting only in sculptris for most part, as I have little luck with blender.Some things work ok others not at all or slowly so I tend to stick with sculptris and export as needed to blender obj. I can only wish I had zbrush, that is one amazing program, although if someone gave me mudbox I’d be overjoyed too ;)) Btw, knowing too many verts can be horribly bad for game dev, I d o indeed try to keep things reduced where possible, and increase verts where I want detail for a given reason. Sculptris is no zbrush, but its just amazing in what its allowed me to do thus far. I need to get out my Wacom 12" tablet and see if I can do better but as I learn and create so hopefully too will my work get better. I’ts rough being a sole dev but somebody has to do it :wink:

Awesome just what I was looking for :wink: Last hour or so I was trying to get down as far as I could in sculptris , cutting tris in low impact areas (plot points) and I got down to 65k, so that should suffice as you noted ( half).

I’ll work through this and get back if I get stuck, ty so much for the valuable info :wink:

Btw, absolutely awesome ocean and weather project , I’d love to try it soon, once I get the ‘basics’ in place and working satisfactorily ;))

Doing game dev is so rewarding, but as a solo indie its sometimes been grueling but certainly a learning experience .


The geometry is covering too much area, as a landscape the lightmap is not going to be high enough resolution. As far as retopologizing is not something that can be done automatically, you have to model on top of your high-detail mesh by hand. Zbrush has the best automatic retopology tool but it’s still not as good as doing it by hand. Ultimately though you need to construct that landscape differently, there should be a number of different elements that create it. Probably what would be best would be to create a number of rock meshes that you would use to add some detail to a couple of low-poly landscape meshes. There could be some larger meshes for things like the spires and then small rocks scattered around. Ultimately you’d want a set of elements you could use to construct it. Take a look at how some other games have done landscapes. Some of them even have a modular setup so that pieces can fit together.

No problem! :slight_smile:

One quick note I would save a copy of your current file, then create a duplicate in sculptris to work on. I am not sure where the option might be, but most sculpting programs have a “Subdivision Level” type of setting where you can choose how many polys get rendered, usually it has a scale of 1-5 or so. This would be the simplest way to reduce the polycount, although it could also be done within blender manually if needed, but that is never fun to do. :smiley:

Let me know how it goes!

I have no clue what you mean by, covering too much area, but I think to keep things 'simpl’e i’ll take dotcoms advice and try that route as it accomplishes just what I wanted perfectly.

Oh btw, this is not my landscape, its just a mesh, that sits on top of the landscape :wink: THe landscape is 3 or 4 times larger than this puny thing ;)<heh>

Sorry if I didn’t make that clear before.

I used sculptris to retopo, using its reduce mesh brush which works wonders, and I’m going to take dotcoms suggestion and use XNormal and see where it takes me, as he claims I can get by fine with half of the 148K as a lowres version along with normal map allowing me to lose practically no detail which was my goal from the beginning.

Thank you so much for taking the time to assist, I value all opinions as they come from the right place :wink: I am actually creating some rocks to add here and there as well as once Im satisfied with this, I’ll texture it .

Thx everyone for weighing in,I feel like I’m on the right path finally.

I started out sculpting, to get my feet wet and as I sculpted, the plot came to me as did the subsequent touches. It’s all a learning process on the road the developing though at some juncture I sure as heck hope to find help.


Ya, sculptris is how I got it down to 65k, by using reduce brush which is just positively priceless for this kind of game dev work. Yes also, sculptris is just amazing for being able to add detail as you want, which is what I’ve done since day one. I’ts one very handy tool, and given my income range thank god its freely available. One day I hope to obtain mudb or zbrush .

I shall update, and ty for your interest and for assisting me today and oh btw, - I got the Xnormal app working but the normal map looks a tad odd, I wonder if the uv map is still too complex, what do you think does it look ‘ok’ ? :!20394&authkey=!AAzoNumVHG-suM8&v=3&ithint=photo%2Cjpg

I’ll try it for now unless I here different, I just have very little exp. creating these items.


I am not an expert in this, but from that UV image posted, it looks like the model is pretty big (Approximate size: 200020001800). I believe that is 20 meters? which I think is a big mesh. For a mesh that big (if it is that big), I think 1000 polys is too low. I think 10K to 25K is pretty normal for such a mesh?

Also I think it depends on how close the player gets to the mesh and what is its intended use.


Can you be more specific? Can you post pictures of the mesh within the Static mesh editor and also in the level (before and after light building)? Also make sure the UV map has no overlap and it also has pretty good resolution. If the mesh is big, you will need higher resolution light map.

I created a new cave in the process of lowering path enough so player doesn’t literally go flying done steep area ,gez ;0-0

Love the new cave, I’m getting better at this,and thx everyone for reminder that low res matters where possible ;)_