Need Help With Normal Maps in Maya
Hi there, so I've been struggling the last week or so with normal mapping for a project and I've read documentations everywhere and for some reason it's not clicking with me and either I A) Forgot entirely how to do this process or 
Never learned correctly in the first place. SOOOO I'm looking for some help and explanation and would prefer if someone would be willing to jump into Google Hangouts or something like that where I can share my screen and or files and get some one on one tutelage in this.
Never learned correctly in the first place. SOOOO I'm looking for some help and explanation and would prefer if someone would be willing to jump into Google Hangouts or something like that where I can share my screen and or files and get some one on one tutelage in this.
Replies
https://www.youtube.com/user/handplane3d/videos
Normal maps aren't going to make a bad lowpoly model look great.
I would recommend practicing proper normal mapping techniques on a simpler object. The foundational knowledge will carry through to more complex pieces. You can check out the Polycount Wiki on normal maps here.
EarthQuake's thread on how to set up a mesh for predictable normal mapping results is also an excellent read, though perhaps you can save this read for later until you get the basics down.
I would also recommend this thread that is dedicated to hard surface modeling. Doing a few of these will greatly help understanding how/where to place supporting edge loops to make the high poly look nice and clean.
The smaller compartment mounted on the front will bake better than the whole front door area, although when it comes to your low poly, that small compartment needs to be broken down to a simpler shape.
Thanks for the help, not trying to be difficult just trying to figure it out >.>
If this model is going into a game engine, your low poly in your wireframe shot above is simply too dense. Most of your pieces could get away with being closer to the density of the image below and let the normal map take care of the rest.
If you're doing this for film it doesn't really matter but it always helps to maintain good practices.
With cleaner LP geo, unwrapping is much simpler and faster, and you could even save a lot of UV space cutting out smaller details that the normal map can take care of.
Your UV is also a little strange. There are bits (top left for example) which have meshes inside of a bigger mesh loop? is that 'spare' space your putting those in? if so then really the 'loop' around them could be attached else where to other parts of your uvs.
If you want some pointers, and if I had time I could look at the scene, would need to see what is going on in the Low to see how to fix your issues.
Until then, I can talk about your UV map a bit. You have a lot of long, thin bits that could probably be attached to other shells to consolidate your texture space. For example, you have the rim of the front door as a separate shell (that racetrack looking piece at the top left). You could instead bevel the edge on the front to keep the door one piece, like so:
The top UVs correspond to the model on the left which represents how you currently have your UVs; the right model (bottom UVs) could be an alternative.
You also have a bunch of tiny bits down at the bottom left. Not sure what those are but there's no way those parts have good texel density.
It looks like you still have a lot of parts on your low poly that the normal map could take care of. The hinges of the door look totally flat, and that little rectangular card on the left probably doesn't need to be there.
The feet of the fridge are so small and insignificant that you can probably get away with leaving the whole thing as one shell. The small circular inset to the left of the handle can be taken care of by the normal map. You can cut all those edges out of your low poly. If you get a poor bake, make the high poly inset slightly scaled inward to avoid angles in your high poly that would be perpendicular to your low poly surface.
Also one other thing: do you intend to have this machine open up to see the inside? If not, the entire body of the machine could be one mesh (for the low poly). You don't need to separate the mesh at the seal of the door, just continue those polygons all the way to the back. Forgive me if I'm seeing this wrong, the wire frame is a hard to see clearly in that area.
I can kinda see what's happening on a lot of this but I don't know exactly how to fix it, especially like the soft curve on the edge of the door like you can see in my render above.
And yeah the texel density is definitely a problem. Most of those really tiny bits belong to the hinges but I though they weren't going to be significant so I didn't worry about them.
https://dl.dropboxusercontent.com/u/53492856/CokeMachineLowPolyRedoUV.mb
that's a link to the Maya file
The UV unwrap feels almost like an Automatic Unwrap. There are a lot of elements that could be stitched and some that could be stacked; some of your mesh could be optimized better to allow for a much greater use of your texture space. For example, the floating panels on the back of the machine could be merged into the main body which would save you all the texture resolution of those floating panels. Same with the front panel to which the handle is mounted, that could be part of the front door.
Left panel: Your configuration, 178 tris
Right panel: Merged configuration, 222 tris, 50% less UV space used
You have various bits of geometry that could be covered using the normal map (have faith in it's capabilities):
1) The bands running along the side of the machine
2) The seal of the door could be removed or at least reduced to a single inset loop
3) The hinges for the panels on the front could be reduced to a single cylinder or removed completely
Mesh Integrity:
1) Flipped normals on the small tag on the left side
2) Flipped normals inside the cap remover
3) Excessive edge loops on the front box portion (the thing with the lever on it)
4) The polys on the underside of the machine could be deleted (you already have this on the feet, may as well get rid of that whole bottom part too)
5) The oval piece to the right of the lever goes way too deep into the compartment it rests in front of. This wastes a small amount of texture space
6) You have lots of edge loops that you continue all the way around your asset when they could be tied off at closer points. In the image below, both shapes are exactly the same but the top one is 162 triangles while the bottom is 400.
Basically, floating geo is just fine to use but sometimes it's a balance between a simple mesh and optimal texture resolution.
I want to say you could get your triangle count down to 2000 or so and still retain all the details of your high poly with a normal map applied, and have a much better texel resolution to boot.
is something like this better or am I still missing it?
Okay I see it thanks