Normal map problems

OBlastradiusO

I dunno why this is but i have a guess. The high poly mesh has a trim but it wont project right and projects artifacts all over the model. How can i fix this any suggestions? I have no overlaping uv's and it's smoothed once. Could it be that the trim has 90 degree turns in it therefore projecting the mesh oddly?

Kawe

uhm, what does the lowpoly look like?

I don't think normal maps can project anything that is perpendicular to the surface, heh.

OBlastradiusO

Ah i see. So how do go about projecting this trim without overlapping? Should I project the HP trim on a plane and copy and paste the normal on photoshop? Well the red arrow points to the high poly trim on top of the low poly building. Thats the pic on the left.

Eric Chadwick

Looks like the pieces pointed out by the white arrows are coming from the other side of the building. Did you reset the Projection cage, then manually Push it back out? Maybe you pushed it too far, or maybe you used a very large ray distance.

OBlastradiusO

EricChadwick wrote: »

Looks like the pieces pointed out by the white arrows are coming from the other side of the building. Did you reset the Projection cage, then manually Push it back out? Maybe you pushed it too far, or maybe you used a very large ray distance.

I did play around with the cage and did what you said but same results.

Eric Chadwick

Could you show us a shot of just the highpoly mesh, and another of the low-poly in the viewport with the Projection cage shown?

Art1977

sorry my post landed in the wrong thread.

OBlastradiusO

Np man. Hey Eric here my high and low poly shot.

Eric Chadwick

You should really have a high-poly mesh for the main wall too, not just the trim. This should solve the problem.

Neox

and i would not make the trim that rectangular, what do think will come out of this? looking from the side it's only a soft bevel with 2-3 pixels height, instead of doing it with 90° shape i'd try a 45° shape

EarthQuake

It looks like you're trying to unwrap this entire thing uniquely, which really makes NO sense what-so-ever. You want to look into creating some tiling textures(you can still make highpoly stuff for tiling textures)

OBlastradiusO

Ill try out all three methods thanks guys

OBlastradiusO

Eric making the main wall an hp did work thanks! I will try earthquakes method too even though i have trouble making these tiled textures and i have to carve up my model. It seems to be more of a pain to me, but ill try.

EarthQuake

Well the thing is, you're going to use like 10x more texture memory to do it all uniquely, and that really just isnt acceptable in a production environment, so its good try to stick to some restraints that you would be expected to use if this was your job, you know?

OBlastradiusO

True true. Im trying out that techique again. Do most game companies you the tiling method for there building enviroments? Also if I tile i have to put dirt, AO, etc in its own channel right? Also when it comes to modular building should i use tilling in all four corners of a 2048 sheet or a single sheet?

EarthQuake

Well, there are no in-stone rules, but i'll cover some basic practices;

Usually, you want to make modular sets, and pile them all on the same texture, so a good example would be, a 1st story tile texture, a 2nd story tile texture, and interior tile texture, and then a variet of trim textures to break things up. Also unique textures for things like windows, doors, gutters, etc. And you want to fit those all onto a single texture if you can, so that you could render the entire building as 1 material. This would be optimal, but spliting it up into 2 textures for example isnt going to kill anyone.

As far as AO goes, you generally want to create a 2nd uvset that you render your AO to, and that will get multiplied onto your mesh in the shader, engines like UE3 will generate this for you IIRC.

And dirt, well theres a few ways you can get variation, one of the easist things to do is create a set of decals that you can apply on top of your mesh, this is what i would recomend. You can also set up a system where you can blend together 2 textures, either with a texture on a 2nd uv, or vertex colors. That way you can have a "clean" texture and a "dirty" texture. And blend them together to get "unique" detail. This way you can also pack more detail into your textures because you dont have to worry as much about how they tile(because you can break them up).

OBlastradiusO

Great explanation im starting to get it now.

EarthQuake

I never got around to finishing this, but it explains a lot of theory stuff and i go into the planing stages quite a bit, which is generally the most important

http://boards.polycount.net/showthread.php?t=54178

Eric Chadwick

Added a link to that in the wiki. Thanks EQ.

OBlastradiusO, some great info about modular techniques in the Environment Modeling section:
http://wiki.polycount.net/CategoryEnvironment

OBlastradiusO

Heres what ive been up to. This looks like the proper way to tile. What do you think?

OBlastradiusO

EarthQuake wrote: »

Well, there are no in-stone rules, but i'll cover some basic practices;

Usually, you want to make modular sets, and pile them all on the same texture, so a good example would be, a 1st story tile texture, a 2nd story tile texture, and interior tile texture, and then a variet of trim textures to break things up. Also unique textures for things like windows, doors, gutters, etc. And you want to fit those all onto a single texture if you can, so that you could render the entire building as 1 material. This would be optimal, but spliting it up into 2 textures for example isnt going to kill anyone.

As far as AO goes, you generally want to create a 2nd uvset that you render your AO to, and that will get multiplied onto your mesh in the shader, engines like UE3 will generate this for you IIRC.

And dirt, well theres a few ways you can get variation, one of the easist things to do is create a set of decals that you can apply on top of your mesh, this is what i would recomend. You can also set up a system where you can blend together 2 textures, either with a texture on a 2nd uv, or vertex colors. That way you can have a "clean" texture and a "dirty" texture. And blend them together to get "unique" detail. This way you can also pack more detail into your textures because you dont have to worry as much about how they tile(because you can break them up).

ONE more question. Couldnt you use decals through max's composites for more complex buildings rather the planes or both?

Eric Chadwick

Composite map is not supported by most engines, because it basically isn't very efficient. It also only makes sense for something that is composited across the whole geometry, like a lightmap.

A decal is usually used only in one spot, but using Composite means Max has to calculate the compositing across the whole mesh to make sure it only shows up in that one spot. Not efficient.

A floating plane means only the transparent parts of that plane have to be calculated.

OBlastradiusO

Okay great. With the floating planes. If i was to export my model to Unreal 3 etc would i need to export that along with the Decal planes?

Eric Chadwick

No, UE3 uses a special setup for decals. I'm not a UE3 user, but these tuts might help you.
http://www.hourences.com/book/tutorialsindex.htm

SHEPEIRO

composite layers can be used quite a bit but not for decals, they would be to time consuming to setup, floating polys is the most widely spread. use composite for large areas such as floors, plain walls, and cliff faces etc