Gamedev: Don't believe it's a seam issue. Here's 3 of them side by side, the one on the left is vertex baked, the 2 on the right are both 512 light bakes, one rotated 180 degrees. There's certianly a seam issue on the top, but more importantly the light bake simply makes the objects too geometric. I suppose i could bump up the geo, but I'm trying to save tris for future assets. Thanks for your time!
In that case, try to unlink it from your material, save the material, then plug it in and save the material again. Dunno why but this seems to solve a similar issue I had recently.
On another note, I'm in need of some help myself.
There seems to have been some rather awkward bugs lately in Ut3, at least so I believe.
Whenever I bake light maps on a model that doesn't have a second uv-channel and overlapping uv's it obviously comes out horrible.
So, I go back into max, fix a second uv-channel and apply a flatten mapping to it with no overlapping faces. Re-export the mesh and import it into ut3. Re-bake, and it looks like this:
I did change the settings for which channel the light maps should be baked to, channel #1 as in the second uv-channel in max (and switched between the numbers without it solving the issue)
So, it seems to me that it bakes the light map in the correct uv-channel then applies it using the first? Which kinda pisses me off as I never had this issue before, except from this and the previous week
As mentioned, I did try changing the settings for which channel it should bake the lightmaps for. And I also tried re-starting the program, then rebaking, and it remains the same.
Yep, lemme post a very simple write up of how to fix it so you don't have to search through the thread too much:
1. Export your object as an *.ase BUT CHANGE THE NAME to be a unique new *.ase file, DO NOT save over your old one.
2. Import the new file that UT3 has not seen before (you can change it's name now to match the old mesh name so it replaces it)
Presto! It's really that easy. Oh and then flip the light map channel in and out per usual.
Thanks guys, appreciate it. Should've used the search function, a bit lazy, I know. But were so tired and slightly pissed atm that I couldn't bother
/edit: seems that didn't fix the issue either. I have had the explained issue before, so I'm grateful for the solution to that.
However, whenever you tile your material in max using the material settings it'll automatically re-size your uv's. So turns out I used up 200% of the 0-1 area for my lightmap, thus causing the error. Just thought I'd mention
Flipping green worked for all my objects EXCEPT the red tank... actually i just applied a base normal map, of the flat default normal blue, and it still does the exact same thing, when it is not applied, there is no seam, what could be the cause of this? The smoothing groups are correct, and UV's are not overlapping...
I actually was having the same issue just the other day. Not sure this will work for you but you can try it. If your object has a UV seam across the middle on channel 1 it's a good bet that this will work.
1. Move all your existing UV's up 1 channel
2. Create a new UV channel 1 and do a quick planar map or sphere map that gives you the least seams in the best possible places.
3. Reimport your asset and adjust your mats and light channel accordingly.
Whats up, guys! I'm in a bit of trouble here and I really could use some help.
I'm simply trying to make a vehicle with trasnparent windows. I was shure that this just couldn't cause any problems, but unfortunately it did, and having browsed some internet I haven't found an answer. I really feel like I could've missed something obvious, but anyway, herer goes:
When I look at the material preview on a box or a cylinder or whatever it looks fine, as shown on the picture. But once I apply it on the model it turns into a mess. The model seems fine. I tried applying it on the other model and the result is the same so it must be the material.
Any help would be much appreciated. And thanks in advance.
Hey guys. Anyone have a clue on how to set up a custom cam in unreal and bind one of the viewports to it?
I would like to try and set up the same view and angle i have in the max-scene and change fov and things like this. Also. If you can freeze movement that would be awesome.
Is this possible? I'd prefer not to use my perspective camera all the time
EDIT: Ok i found out how to create a camera and customize it but not how to lock the viewport and see from the camera. Hmm.
Hey guys. Anyone have a clue on how to set up a custom cam in unreal and bind one of the viewports to it?
I would like to try and set up the same view and angle i have in the max-scene and change fov and things like this. Also. If you can freeze movement that would be awesome.
Is this possible? I'd prefer not to use my perspective camera all the time
EDIT: Ok i found out how to create a camera and customize it but not how to lock the viewport and see from the camera. Hmm.
Here's the button you're looking for. It's the small eye next to the maximize viewport button. Just click it and then click on an actor. Any actor that 'points' out in some direction, like a camera, will have that view locked to what the actor sees. If you use your mouse look/move you can also move the actor around in a first person sort of way; just be careful as I've found the button to be a bit finicky and it's rather easy to accidentally zoom an actor across the map. You can lock the movement of the camera from within the actor properties so that you don't accidentally move your camera.
Lamont, Jesse Moody, thanks so much for your reply guys.
If I got you right, you're saying that I should just have two meshes with two materials. I've thought of it and even almost did it, but stopped myself to aks you guys, 'cause I really don't believe that this could be a rational solution in a tool of such a level.
Imagine me doing a racing game with 60 cars simultaniously on the screen. To have transparent windows I'll have to double(!) the amount of drawcalls for cars per frame and that really sounds to irrational to be true. Or doesn't it?
I'm really kinda confued wright now, and I'll probably will do as you guys said, for I just need to get a picture. But I'm very curious about how this thing actually works.
I think what he means is using 1 mesh, with 2 materials.
If you're using 3ds max, then it's a simple matter of creating a multi/sub material, and use material id's to control which part of your model should use which material.
Then while your mesh is imported into ut3, there should be 2 material slots instead of one for the object.
Googling it should be able to find you a more elaborate explanation. I'm kind of short on time right now
Hey,Tiros, thanks!
Yeah, thats an option too. And a better one i suppose.
But as far as I know enginewise different materials means different drawcalls anyway. So My main question is still up.
Hey,Tiros, thanks!
Yeah, thats an option too. And a better one i suppose.
But as far as I know enginewise different materials means different drawcalls anyway. So My main question is still up.
It has to be done, some games do them as completely separate meshes since the cars break and stuff. You're tagging the whole car as an alpha blended material/object. Do this for cars that are in the 15~20k poly range and you can see why a different material/mesh is needed.
It has to be done, some games do them as completely separate meshes since the cars break and stuff. You're tagging the whole car as an alpha blended material/object. Do this for cars that are in the 15~20k poly range and you can see why a different material/mesh is needed.
unfortnately I can't do it, so I'm just trying to figure it all out in my head.
As far as I can see aplha blending isn't that much of a complicated operation(if you don't render double sided polys at least). You just render you polys according to z-buffer and in the places where you have opacity you don't just replace the underlying pixel, but mix the two by the straight forward signle variable that is in your opacity mask. And I'm not really shure if it has something to do with polycount rather then texel count.
Does this one additional operation cost so much, that it's cheaper to request another drawcall?
Well it's obvious that opacity blending is additional stress to your engine, and I know that it ain't widely used. We use it only in case of extreme nescessity, but i just though that our inhouse engine wasn't cut out to work too well with this stuff. Is it really so bad, that you've gotta call for another drawcall, and most importantly "why". I'm sorry I'm just feeling extremly curious about it.
And I've tryed loading a mesh with multiple material ID's into UE but somehow it didn't workout for me.=(
I made a multisub object and assgined all the material id's. Then exported to .ase . After import when I look at my lod info in my static mesh editor theres only one material slot. I tryed googling, but haven't found anything that helped. Any help would be greatly appreciated!
Good day verybody.=)
Are you using the UED exporter or a generic *.ase exporter? You said Multi-Sub, which means 3DS Max. No clue how 3DS Max does the export for UED and what it requires. But get multiple materials on the mesh, or just separate the glass from the body in 3DS Max, then join them at export.
d1ver to get the multisub material to work make sure you apply at least one texture to each sub material for each material ID within Max, otherwise the different material IDs won't get transferred to Unreal through ASE export.
Lamont and Ben, thank you guys. It's finally fine. I tried to export t with two identical DirectX shaders as multisub materials.)now i know I shouldn't.
Anyone know of any cool advanced lighting tutorials for UT3? About to start tackeling more lighting for the unearhtly challenge and want the lighting to look nice.
I've been toying with small negative values on lights, getting some pretty cool results, nice for accenting areas of the scene. But i'd rather the light behave more like a fog and not affect surcfaces base on their facing, simply their proximity, any way of achieving this?
Actually any kind of high end trickery tutorials for making a unreal level look snazzy would be cool!
Anyone know if there's statistics inside the editor?
Would like to see triangle counts and such. Having no luck with searches. Still no clue about the camera but I can at least change ingame FOV.
I don't have it open, but I think "stat engine" is the one you want. Also if you look in the generic browser there's the world info tab. Double click that.
Ah. I was looking around for what you said but couldn't find any of them. No world info tab either. After awhile I found the tri-count under "primitive stats".
Thanks Lamont. I wonder if i should pay attention to instanced or just regular triangles.
I wonder if i should pay attention to instanced or just regular triangles.
Depending on the size and complexity of the scene, I'd be more interested in regular triangles. Worth keeping an eye on instanced figures, too, though.
hey guys I made this platform in unreal that moves up quickly when you stand on it, so like an elevator, it used to work ok but now when you step on it the character is jumping all the time making it impossible to keep yourself still on the platform. Does someone know what causes this?
hey guys I made this platform in unreal that moves up quickly when you stand on it, so like an elevator, it used to work ok but now when you step on it the character is jumping all the time making it impossible to keep yourself still on the platform. Does someone know what causes this?
sounds like the collision is interfering with the the character. You could try and hard attach a blocking volume around in the floor of the elevator, so that the surface is straight, if the mesh you are using for the elevator isn't. a screen shot would be easier to see the problem
Hey elementrix - I think there is a flag for whether or not a pawn can base on an object. If this is set to false or off, the player and other physics objects will act as jumping beans when on moving interp actors. Worth a try!
How do I get proper vertice blending setup in 3ds max?
Are you attempting vertex paint in max for using w/ blending in the engine? In edit poly, in vertex mode, you can select verts and then under 'Vertex Properties' you can set color information. You can also use the Vertex Paint modifier.
To view your vertex color inside of max, go to the meshes properties (right click, 'Object Properties') and under 'Dispaly Properties' check on 'Vertex Channel Display'.
When exporting to the engine, ensure you export vertex colors.
Found some cool UT3 adjustments that I thought i'd share, figure someone might want it with the end of the UC coming up:
View> World Properties> World Info> Scene Midtones
Tweak these to have slightly higher values and a washed out scene will quickly start looking cool again. You can play with highlights and shadows if you want, but the real powers in the midtones.
i think the first version was better readable, if you wanna stick with the second, i'd say add a bit of fog, as its really hard to make out whats going on there
Anyone know why Ii get so dimmed lights in the scene? Is it just a case of uping the brightness on the lights or am I missing some kind of fancy function/button anywhere?
And is there a way to change the gizmo? If i rotate a mesh upside down I'd prefer it not to be local, World orientation possible?
crazyfingers: Those are actually standard post-processing adjustments. So you don't have to go into the world settings, you could just create and change this directly in your post processing volume. Not saying it's a bad thing doing it in the worl settings, just thought I'd enlighten you, though
Notorious: For the lights, it could be the post-processing that needs to be tweaked a bit
As for the gizmo, up by the Translate / Rotate / Scale buttons there's also a dropdown menu where you can choose between Local and World.
Until this afternoon, I was using the UE3 editor that shipped with UT3. Of course, now I've downloaded and installed the UDK, but I'm still encountering an issue with crashes.
I'm trying to import a small (10k poly) .ase file into UDK, exported from Max 2009. I've checked that there are no rogue splines left in the scene, and everything seems fine in Max. I attempt an import into UDK, and it crashes - every single time. Obviously this is a gigantic pain in the ass, as it's making it supremely difficult to check how my textures look in-game.
Can anyone think of any other factors that would cause a consistent crashing error?
The only trial and error method I can think of would be to delete a large portion of your mesh and try to reimport the small chunk. If the small chunk imports correctly then there is a problem with the other chunk in your mesh. If it still crashes, then maybe there is an inherent problem with the entire mesh file.
You might also try exporting the entire thing as an OBJ, then reimporting it back into Max before sending out your ASE. Sometimes that'll clear up weird anomalies.
This is probably irrelevant for UE3, but I always forget to triangulate my mesh and have to go back and do that when importing something into a game engine... possible, just an idea. Usually something stupid like that with me.
ALSO, if anyone reads this I am having an issue with UDK and am posting my question here because I already had this pointless post to edit. Sorry about that. Ahh, so, I use dvorak. I can switch the key input for active programs back to qwerty, which lets me use the wasd controls for camera movement in the viewport. However, this is inconvenient and the editor is constantly refreshing, switching back to dvorak. I can live without wasd camera controls, but was curious to know if there is any config file I can change this sort of setting in. I found some keybinding config files, nothing about wasd, except being able to disable it.
Anyway, feel free not to respond because it's not necessary that I configure this at all. I do not know why I am even posting it, but I was stuck with this post here so I figured I'd add something.
Sorry if this isn't quite the right place to post, but the info in this thread has been really good and I've had issues finding this information elsewhere, so here goes:
I have a light in my level set to cast shadows. I have a table mesh sitting on a rug mesh, which sits on a BSP surface. The light casts shadow on the BSP just fine, but the table doesn't cast a shadow on the rug.
I've gone mad trying different combinations of lighting channels and settings to try and make one static mesh shadow another static mesh. Does anyone know what combination of settings I need to get this working? Thanks in advance.
There really aren't any special settings for getting one static mesh to cast shadows on another, it should work "right out of the box" with any light other than a skylight.
It sounds as though you've got your rug static mesh to bake it's lighting info using vertex lighting. It's one of the things that can throw off not getting good shadows on a static mesh. Another problem could be if it doesn't have a proper UV set for a real pixel based light map bake.
Once placed in a level static meshes by default are set to use vertex lighting to bake shadows so unless you build your mesh with a lot of evenly spaced verts you won't get detailed shadows right away. You need to change one or two settings to get it to work right.
First open up the Generic Browser then open up the Static Mesh Editor window.
Set the LightMapCoordinateIndex to whatever UV channel you've set up for your lightmap bake.
Then either set the LightMapResolution here to a power of 2, something like 64 should work good for small objects.
Next open up the properties window for the static mesh placed in the level and scroll down to bOverrideLightMapResolution and uncheck it.
or
If you've left the LightMapResolution of your static mesh as 0 in the Generic Browser -> Static Mesh Editor window then leave bOverrideLightMapResolution checked and scroll down to OverriddenLightMapResolution and set it to some power of 2 number.
Finally rebuild the lighting
By leaving the LightMapResolution at 0 you are telling Unreal to bake that object's lighting using vertex lighting.
Here's a couple of lightmap UV tutorials for Unreal if you need help with that as well.
Hey guys I just have a question about vertex painting in Unreal editor.
I saw that it's possible to vertex paint a mesh in the udk : http://udn.epicgames.com/Three/MeshPaintReference.html but i can't find the mesh paint mode button they're talking about in the editor of the game (the one without lightmass etc)
Replies
In that case, try to unlink it from your material, save the material, then plug it in and save the material again. Dunno why but this seems to solve a similar issue I had recently.
On another note, I'm in need of some help myself.
There seems to have been some rather awkward bugs lately in Ut3, at least so I believe.
Whenever I bake light maps on a model that doesn't have a second uv-channel and overlapping uv's it obviously comes out horrible.
So, I go back into max, fix a second uv-channel and apply a flatten mapping to it with no overlapping faces. Re-export the mesh and import it into ut3. Re-bake, and it looks like this:
I did change the settings for which channel the light maps should be baked to, channel #1 as in the second uv-channel in max (and switched between the numbers without it solving the issue)
So, it seems to me that it bakes the light map in the correct uv-channel then applies it using the first? Which kinda pisses me off as I never had this issue before, except from this and the previous week
As mentioned, I did try changing the settings for which channel it should bake the lightmaps for. And I also tried re-starting the program, then rebaking, and it remains the same.
1. Export your object as an *.ase BUT CHANGE THE NAME to be a unique new *.ase file, DO NOT save over your old one.
2. Import the new file that UT3 has not seen before (you can change it's name now to match the old mesh name so it replaces it)
Presto! It's really that easy. Oh and then flip the light map channel in and out per usual.
I am getting seams, which are not present in Maya, or Marmoset... I assume its from shadows for some reason, but I cant figure out how to fix them.
Has anyone seen this issue before, or know how to fix it?
http://www.jettfolio.com/images/Junkton/seam.jpg
/edit: seems that didn't fix the issue either. I have had the explained issue before, so I'm grateful for the solution to that.
However, whenever you tile your material in max using the material settings it'll automatically re-size your uv's. So turns out I used up 200% of the 0-1 area for my lightmap, thus causing the error. Just thought I'd mention
1. Move all your existing UV's up 1 channel
2. Create a new UV channel 1 and do a quick planar map or sphere map that gives you the least seams in the best possible places.
3. Reimport your asset and adjust your mats and light channel accordingly.
I'm simply trying to make a vehicle with trasnparent windows. I was shure that this just couldn't cause any problems, but unfortunately it did, and having browsed some internet I haven't found an answer. I really feel like I could've missed something obvious, but anyway, herer goes:
When I look at the material preview on a box or a cylinder or whatever it looks fine, as shown on the picture. But once I apply it on the model it turns into a mess. The model seems fine. I tried applying it on the other model and the result is the same so it must be the material.
Any help would be much appreciated. And thanks in advance.
I would like to try and set up the same view and angle i have in the max-scene and change fov and things like this. Also. If you can freeze movement that would be awesome.
Is this possible? I'd prefer not to use my perspective camera all the time
EDIT: Ok i found out how to create a camera and customize it but not how to lock the viewport and see from the camera. Hmm.
Here's the button you're looking for. It's the small eye next to the maximize viewport button. Just click it and then click on an actor. Any actor that 'points' out in some direction, like a camera, will have that view locked to what the actor sees. If you use your mouse look/move you can also move the actor around in a first person sort of way; just be careful as I've found the button to be a bit finicky and it's rather easy to accidentally zoom an actor across the map. You can lock the movement of the camera from within the actor properties so that you don't accidentally move your camera.
Hope that helps.
Yeah pretty much just put the glass on a second material id for best results. That's what I have always done.
You can put it on the first one but well I just wouldn't.
If I got you right, you're saying that I should just have two meshes with two materials. I've thought of it and even almost did it, but stopped myself to aks you guys, 'cause I really don't believe that this could be a rational solution in a tool of such a level.
Imagine me doing a racing game with 60 cars simultaniously on the screen. To have transparent windows I'll have to double(!) the amount of drawcalls for cars per frame and that really sounds to irrational to be true. Or doesn't it?
I'm really kinda confued wright now, and I'll probably will do as you guys said, for I just need to get a picture. But I'm very curious about how this thing actually works.
Thanks again.
If you're using 3ds max, then it's a simple matter of creating a multi/sub material, and use material id's to control which part of your model should use which material.
Then while your mesh is imported into ut3, there should be 2 material slots instead of one for the object.
Googling it should be able to find you a more elaborate explanation. I'm kind of short on time right now
Yeah, thats an option too. And a better one i suppose.
But as far as I know enginewise different materials means different drawcalls anyway. So My main question is still up.
unfortnately I can't do it, so I'm just trying to figure it all out in my head.
As far as I can see aplha blending isn't that much of a complicated operation(if you don't render double sided polys at least). You just render you polys according to z-buffer and in the places where you have opacity you don't just replace the underlying pixel, but mix the two by the straight forward signle variable that is in your opacity mask. And I'm not really shure if it has something to do with polycount rather then texel count.
Does this one additional operation cost so much, that it's cheaper to request another drawcall?
Well it's obvious that opacity blending is additional stress to your engine, and I know that it ain't widely used. We use it only in case of extreme nescessity, but i just though that our inhouse engine wasn't cut out to work too well with this stuff. Is it really so bad, that you've gotta call for another drawcall, and most importantly "why". I'm sorry I'm just feeling extremly curious about it.
And I've tryed loading a mesh with multiple material ID's into UE but somehow it didn't workout for me.=(
I made a multisub object and assgined all the material id's. Then exported to .ase . After import when I look at my lod info in my static mesh editor theres only one material slot. I tryed googling, but haven't found anything that helped. Any help would be greatly appreciated!
Good day verybody.=)
Have not used 3DS Max since v6.
thanks a ton!you guys've been a lot of help.
I've been toying with small negative values on lights, getting some pretty cool results, nice for accenting areas of the scene. But i'd rather the light behave more like a fog and not affect surcfaces base on their facing, simply their proximity, any way of achieving this?
Actually any kind of high end trickery tutorials for making a unreal level look snazzy would be cool!
Would like to see triangle counts and such. Having no luck with searches. Still no clue about the camera but I can at least change ingame FOV.
Thanks Lamont. I wonder if i should pay attention to instanced or just regular triangles.
Depending on the size and complexity of the scene, I'd be more interested in regular triangles. Worth keeping an eye on instanced figures, too, though.
Neox: gonna give the fog volume deal a go, thanks for the heads up.
sounds like the collision is interfering with the the character. You could try and hard attach a blocking volume around in the floor of the elevator, so that the surface is straight, if the mesh you are using for the elevator isn't. a screen shot would be easier to see the problem
Are you attempting vertex paint in max for using w/ blending in the engine? In edit poly, in vertex mode, you can select verts and then under 'Vertex Properties' you can set color information. You can also use the Vertex Paint modifier.
To view your vertex color inside of max, go to the meshes properties (right click, 'Object Properties') and under 'Dispaly Properties' check on 'Vertex Channel Display'.
When exporting to the engine, ensure you export vertex colors.
-Tyler
View> World Properties> World Info> Scene Midtones
Tweak these to have slightly higher values and a washed out scene will quickly start looking cool again. You can play with highlights and shadows if you want, but the real powers in the midtones.
My scene went from:
To:
I was pretty stoked.
And is there a way to change the gizmo? If i rotate a mesh upside down I'd prefer it not to be local, World orientation possible?
Notorious: For the lights, it could be the post-processing that needs to be tweaked a bit
As for the gizmo, up by the Translate / Rotate / Scale buttons there's also a dropdown menu where you can choose between Local and World.
Doh. About the gizmo thing. I never looked up there due to shortcuts for the gizmo. hehe.
Until this afternoon, I was using the UE3 editor that shipped with UT3. Of course, now I've downloaded and installed the UDK, but I'm still encountering an issue with crashes.
I'm trying to import a small (10k poly) .ase file into UDK, exported from Max 2009. I've checked that there are no rogue splines left in the scene, and everything seems fine in Max. I attempt an import into UDK, and it crashes - every single time. Obviously this is a gigantic pain in the ass, as it's making it supremely difficult to check how my textures look in-game.
Can anyone think of any other factors that would cause a consistent crashing error?
I did import a character once, but he was after all split up into multiple meshes. So, did you try splitting the mesh up into smaller parts?
Any other ideas?
You might also try exporting the entire thing as an OBJ, then reimporting it back into Max before sending out your ASE. Sometimes that'll clear up weird anomalies.
ALSO, if anyone reads this I am having an issue with UDK and am posting my question here because I already had this pointless post to edit. Sorry about that. Ahh, so, I use dvorak. I can switch the key input for active programs back to qwerty, which lets me use the wasd controls for camera movement in the viewport. However, this is inconvenient and the editor is constantly refreshing, switching back to dvorak. I can live without wasd camera controls, but was curious to know if there is any config file I can change this sort of setting in. I found some keybinding config files, nothing about wasd, except being able to disable it.
Anyway, feel free not to respond because it's not necessary that I configure this at all. I do not know why I am even posting it, but I was stuck with this post here so I figured I'd add something.
I have a light in my level set to cast shadows. I have a table mesh sitting on a rug mesh, which sits on a BSP surface. The light casts shadow on the BSP just fine, but the table doesn't cast a shadow on the rug.
I've gone mad trying different combinations of lighting channels and settings to try and make one static mesh shadow another static mesh. Does anyone know what combination of settings I need to get this working? Thanks in advance.
It sounds as though you've got your rug static mesh to bake it's lighting info using vertex lighting. It's one of the things that can throw off not getting good shadows on a static mesh. Another problem could be if it doesn't have a proper UV set for a real pixel based light map bake.
Once placed in a level static meshes by default are set to use vertex lighting to bake shadows so unless you build your mesh with a lot of evenly spaced verts you won't get detailed shadows right away. You need to change one or two settings to get it to work right.
First open up the Generic Browser then open up the Static Mesh Editor window.
Set the LightMapCoordinateIndex to whatever UV channel you've set up for your lightmap bake.
Then either set the LightMapResolution here to a power of 2, something like 64 should work good for small objects.
Next open up the properties window for the static mesh placed in the level and scroll down to bOverrideLightMapResolution and uncheck it.
or
If you've left the LightMapResolution of your static mesh as 0 in the Generic Browser -> Static Mesh Editor window then leave bOverrideLightMapResolution checked and scroll down to OverriddenLightMapResolution and set it to some power of 2 number.
Finally rebuild the lighting
By leaving the LightMapResolution at 0 you are telling Unreal to bake that object's lighting using vertex lighting.
Here's a couple of lightmap UV tutorials for Unreal if you need help with that as well.
http://stephenjameson.com/tutorials/lightmap-uvs-tutorial/
UDN - Unwrapping meshes for light-maps
I saw that it's possible to vertex paint a mesh in the udk : http://udn.epicgames.com/Three/MeshPaintReference.html but i can't find the mesh paint mode button they're talking about in the editor of the game (the one without lightmass etc)