Lightmap/AO 3dsmax second uv question
polycounter lvl 18
http://boards.polycount.net/showthread.php?t=54150&page=2
I thought someone was working on a tut for this, but guess it got backburned.
just for noob sake, trying to figure this out I went ahead and followed this tutorial
http://www.game-artist.net/forums/vbarticles.php?do=article&articleid=37
I created a simple box with an intersection, uv mapped it and applied a tiling texture to it.
I then collapsed the stack.
I then created a secondary uv set on channel two, applied a grey texture to the boxes and then rendered to texture following that tutorial and created a AO map.
Now, i have questions, do I need to keep both unwrap uvw's or can i collapse them.
Secondly, how can I add that to a shader in max? Via the emissive channel? A dx shader? Where do i select the uv set to use?
Any help would be appreciated, I think Lee's going to help me with it in Unreal, but I'd like to know how ot show it up in max as well. Thanks.
I thought someone was working on a tut for this, but guess it got backburned.
just for noob sake, trying to figure this out I went ahead and followed this tutorial
http://www.game-artist.net/forums/vbarticles.php?do=article&articleid=37
I created a simple box with an intersection, uv mapped it and applied a tiling texture to it.
I then collapsed the stack.
I then created a secondary uv set on channel two, applied a grey texture to the boxes and then rendered to texture following that tutorial and created a AO map.
Now, i have questions, do I need to keep both unwrap uvw's or can i collapse them.
Secondly, how can I add that to a shader in max? Via the emissive channel? A dx shader? Where do i select the uv set to use?
Any help would be appreciated, I think Lee's going to help me with it in Unreal, but I'd like to know how ot show it up in max as well. Thanks.
Replies
Depends on the shader, you need one that supports multiple UVs.
I got the two uv sets working, but it just doesn't look like I'm putting the AO bake in the right slot. I thought I was supposed to be putting it in the emissive slot but maybe this would all be easier if I rendered it in unreal instead of trying it in max?
thanks again.
Edit, here's a shader you could use.
http://www.bencloward.com/shaders_globalIllum.shtml
like this:
http://boards.polycount.net/showpost.php?p=821730&postcount=25
The bridge is tiling the texture then he autounwraps and bakes out a smaller ao bake
Usually environment assets don't have overlapping UVs for the lightmap or AO map, but it's always good to exploit repeatable lighting when you can.
Ya the composite map works great, I was just playing with that the other day and will be using it alot in the future.
http://www.3dtotal.com/tutorials/composite_material/
Has anyone tried it for that version? I'll give it a shot, see if it works (hopefully it does) I also watched the video tut, very nice info indeed! Thanks.
I am concerned about max 9's ability to do the AO in the 2nd uv method well. Guess i'll have to try and find out!
It's actually a little new to me, i'm used to projecting the AO from a high sculpt to low (or at my old job I used to bake AO vertex maps directly on to the geo the old skool way). I do have a huge use for this technique though. I'll have to give the shader Eric posted a try. I mainly want to bake out small AO maps like Earthquake did for his bridge (he looks like he's using maybe a 128 from what I can see). This method is awesome sauce, i'm working on a scene with some tiling textures that will definitely look better once I get this down! Thanks
Update: Anyone done the AO method with 3ds Max 9? What shader worked well for you...hehe sorry had to ask (If it cuts time down tinkering, then awesome).
There are a few ways to render out AO.
Mental Ray AO:
If you set your render engine (Render Setup > Assign Renderer) to Mental Ray. In the Render to texture dialog (0) it will show up as a map output type.
Skylight:
- You can also avoid Mental Ray by setting up a sky light or a light dome.
- There's a great script for that called Elight Dome http://home.wanadoo.nl/r.j.o/skyraider/e-light.htm It's not for commercial use but it does a great job. What it creates isn't hard to reproduce on your own if you ever have to use something like that on a commeical project.
- Then apply a white or grey texture to your objects and in RTT render out a diffuse map.
I have a large scene, and I've been looking at it, trying to figure out what's the best approach. I think that baking the entire scene would give a more believable AO. I have quite a ton of parts to unwrap. For assets that already have an AO (baked from the high sculpt and in are now in the diffuse) I'm assuming I should leave them out of the new "entire scene" AO that I am now creating.
I have been creating a diffuse map with many overlapping UV's for a house. I then repeatedly render out the UV over and over to reveal the overlapping faces. I take those faces and move them around by 1.0 units until each face has a unique space over the infinite tiling. This is how I have been creating my AO bakes. However each of these faces will share the same AO bake that the face in the original 0-1 UV space has. This I assume is what you mean by the quote above.
From what you say this is not how environments are typically created? With environment UV creation, is it typical to give each face in the scene its own UV space in the 0-1 square so that you do not overlap AO baking? Or am I misinterpreting you?
But most lighting situations call for different lighting, because of different bounce colors, or different occlusion, or whatever. So that means every triangle on the level geometry has its own little unshared chunk within the 0-1 UV space.
Because the resolution really sucks when everything is packed into one lightmap, giving you blurry jagged shadows, games often break up a level into a number of lightmaps. But the less maps the better, because memory is limited and loading new textures into memory is slow.
That is a very effective way to do what I want to do, and therfore an easy pipeline into getting the desired AO result on a 2nd channel. Unfortunately i'm dealing with version 9 (if I attach all geo together and map an AO on a 2nd channel...well problem is they all have unwraps on the 1st channel as individual objects), so i'm going to have to figure out a work around. I'm now thinking I'll have to go through every geo one at a time and unwrap them all quickly.
Then i'm really hoping that this method: http://www.game-artist.net/forums/vbarticles.php?do=article&articleid=37 can be used on multiple geo at once. As I want all of the objects to have light calculated on them to give shadow to the entire scene.
Any ideas?
I'm still guessing that I should leave all objects that already have an AO baked from a high sculpt out of the Lightmap AO texture plate (as they would get double the shadow and look hideous... hehe).
Someone talked about a method for just this issue not long ago, IIRC. A search might find it.
I'm guessing IIRC's a person. Will do
I think i've figured out the problem in my head thanks to your post "Combining them together makes sense whenever the shaders are the same between entities."
I just have to ensure all geo are housed under the same shader. I had them under different shaders due to my viewport being way too slow due to normal maps/direct x shading being on (e.g: I had a regular ball and a normal ball for testing to see if things looked good in the scene). Now i'll put them all under one shader and I should be able to work it out...I wish I was using 2009. I may be upgrading sooner than later!
Because of the difference between creating diffuse and lightmaps, is it really common to use different channels entirely for the lightmaps and the diffuse maps?
Or is it that generally in the industry once the lightmap UV's are created the same UV's are used to create diffuse (does this ever happen?). I realise its most likely subjective more than anything, but im trying to find the typical workflow so I can continue to put myself through a common pipeline as much asa possible.
Microneezia: I'm digging the house on your portfolio site, nice job! Are you going about texturing it as well? Just wondering, wouldn't mind seeing that.
Environments typically use tiled UVs, so you can't simply combine the AO down into the diffuse. Also characters don't use lightmaps (baked shadows, bounce light, etc.) but environments do use lightmaps, so that's where the second UV set comes into play. BTW, IIRC means if I recall correctly.
http://users.skynet.be/arketip/arketipToolboxENG.htm
Two scripts there, the Multi-unwrap and the Pixelpack one.
EricChadwick: Question about http://maxplugins.de/max9_32.php?search=blendmodes&sort=Author I put it in the Max plugins folder C\Program Files\Autodesk\3ds Max 9
I can't seem to find it in Max (not appearing at the top bar like the rest of my plugins, like EPHERE Utilities and the like). Quite strange indeed.
WOOT! There is a multi-unwrap
PS PixelPack looks like multiObjectsUnwrap on god mode
http://www.scriptspot.com/3ds-max/tutorials/script-installation-in-3ds-max
im texturing the house now as we speak, im just re-UVing the thing properly, Ive been blocking out an Unearthly Challenge entry lately so Ive left my texturing on the back burner, Liquid D. asked me to texture the house though, so I dropped the UC for a couple days, tomorrow evening you should see the full house textured if you look back at my site... thats what I told Liquid anyway.
thanks for your help.
Oh here's an archive I happened to find from a google search (just happens to be polycount...wonder why, hehehe)
http://boards.polycount.net/archive/index.php/t-34439.html
looks like some oldies but goodies. I definitely got PSD Path Unwrapper, but I think I still need to get textporter.
I'm taking the first night off in weeks of solid working. Getting back to the grind first thing tomorrow! This threads been plenty of help.
Perhaps if you have a seperate channel for the lightmap (with the flattened auto UV's) and a seperate channel for the diffuse (with many faces welded and sharing the same spot) you RTT a diffuse map?, and that would combine the 2 maps into one single map?
Is that what is typically done? Is the AO map commonly a seperate map all the way through? Cause I still dont see how I can manipulate the AO map in photoshop on a seperate layer from my diffuse if the AO is not sharing space and the diffuse is. Perhaps multiplying the AO onto the diff in photoshop is mainly a character thing?
For characters/weapons, typically the lightmap is merged down into the diffuse map. For environments typically the lightmap is a separate bitmap, using its own separate UV.
As the AO map isn't taking up a separate map, it's not necessarily taking up extra memory. It also makes your diffuse look a lot more detailed! Again this is for key assets that won't tile, as others have stated earlier that for Environment work you usually wouldn't use this method. Instead you would use the 2nd UV channel and have a seperate AO map.
It depends on the studios pipeline, but I feel that future pipelines (by seeing some of the newer games like Gears of War 2) will have their own in house solution to deal with real time AO.
Perhaps look into using Earth Quakes tutorial which EricChadwick already posted below.
(link to EQ's tutorial is 9 posts down) to make yourself an AO on a per asset basis using Xnormal (by polycount member jogshy).
T-train- you can bake AO into tiling maps/objects diffusemap, but only bake in per object lighting.
Im also pretty sure that games like GOW2 will be using lightmaps, they will just be using them in fancy ways, along with other info baked into the scene. real time effect, but baked information
something like this probably but on a scene scale
http://www.valvesoftware.com/publications/2007/SIGGRAPH2007_EfficientSelfShadowedRadiosityNormalMapping.pdf
Hey Eric or anyone, I thought I'd do a quick test with StandardFX.fx shaders. I must say they are way better than the "DX Display using standard material" that i've been using in the past on games.
I've run into a problem though, it seems that the diffuse, spec, & normal show up just fine in viewport but my AO on a 2nd channel doesn't show how it's supposed to. It doesn't matter what channel I change it to (2 or 3) with different mapping...it just appears as channel 1's mapping.
A big problem, as I need to have my AO Lightmap in the 2nd channel for the entire scene... any ideas?
I googled the problem, and found someone else who seems to have it too.
http://discussion.autodesk.com/forums/thread.jspa?threadID=538188
I'm using 3ds Max 9...i'm wondering if that's the problem?? I need to solve this...real soon
I received a msg from Ruz, and he was real helpful. Apparently it works just fine in Max 2008...so It's time for an upgrade.
I upgraded to 2009 though, and it fixed the weird problem with standardfx.
I can actually see the AO map moving around in the viewport (like a slippery ghost) when I move uvs in the editor on channel 2. It's pretty cool.