Hardening edges in Max

sheckee

Hi guys,

I had a quick search for this but I don't really know what terms to search, so hopefully someone can give me the answer.
I used to use Maya, and you could select edges and under Normals hit 'Harden' or 'Soften' (or set the value to whichever you like) - which was really great.
I'm struggling to figure out how to achieve this in Max, smoothing groups seem to effect all of the edges surrounding the face, what if I just wanted to effect only one edge?

I hope this makes sense.

Thanks!

sulky

There is no hard edges or soft edges in Max. You can achieve pretty much the same result with the smoothing groups in the edit poly modifier or your regular editable poly geometry. They work pretty simply: face in the smoothing group 1 are smooth with each other. Same goes with all the groups. When the faces from two group meet they create a hard edge.

sheckee

I get that, but your sphere there has multiple hard edges. What if you just wanted that center edge to be hard, and the rest soft? You can do this in Maya, but not Max? There must be a way..?

sulky

Like this ? I just took all the faces on 1 side and assigned the smoothing group 1 and for the other side the smoothing group 2. This is the equivalent of the hard/soft edges that Maya use.

Justin Meisse

if say, smoothing group 1 and 2 are touching at an edge that you want to be soft but you don't want them to share the same group: set the faces bordering that edge to group 1 & 2. It sounds annoying but it's not a situation I bump into a lot.

To make things easier, avoid messing with the number buttons. Most of the time I'll have "by angle" checked to select large groups of faces and then hit "Auto Smooth" with the value turned up to max (180). Plenty of times I can just select the whole model and fiddle with the auto smooth value to get everything sorted out quickly.

I was using Maya for about 7 years when I switched to Max, which I've been using the last 7 years, it was frustrating when I started but I don't even notice it anymore.

kurt_hectic

Try this:

http://www.scriptspot.com/3ds-max/scripts/edgesmooth

gsokol

I bounce between Maya and Max quite a bit......definitely not a fan of controlling edges with smoothing groups....I prefer the way maya does it.

@kurt_hectic: I've never seen that script before. You just made my day.

Noors

Yeah i think the only advantage of smoothing groups over edge control is face selection. Setting smoothing groups to get only 1 hard edge in the middle of a sphere is a bit of mind gymnastic but doable.
Pjanssen's script does the gym for you

sheckee

Great script! Thank you!

sheckee

Bugger! I guess the best way to describe my predicament is in the example of the crease of the nostrils meeting the cheek, or maybe the crease under the lips etc. I just wanted to harden that crease, but obviously changing the smoothing groups for those faces will harden all of the edges. I guess I need to break the geometry along that edge or add more geometry?

sheckee

Thank you Perna, I'll have a play around during my lunch break today; if I can't figure it out (based on your clue! ) then I'll put an image up. Thanks for your help.

Mark Dygert

Maybe this will help.


When it comes to smoothing you have to get out of the mindset of working in edges and start working in groups of polys. These polys go into this smoothing group, those go into another and where they meet the smoothing is broken.

Smoothing often breaks at UV or material seams so if it helps to think of the smoothing, as groups of polys like in a UV layout, and group your polys that way it make unwrapping a little easier because you can explode unwrap based on smoothing groups.

Once you start working with smoothing in groups of polys, you can do things like select polys based on smoothing groups.

Both Max and Maya are using different methods to do the same thing, break and unify normals. You can edit the normals directly by applying an edit normal modifier, but it's pretty tedious and smoothing groups, once you get the hang of them are pretty easy to work with.

Technically the far right example could have the caps in the same smoothing group and they would produce the same result. This would happen because they are separated by polys that aren't in their group. That way not everything has to be in its own smoothing group you might run out of smoothing groups in you did that.

So instead of 1-2-3-4-5-6-7, you can go 1-2-1-2-1-2-1. That way you can get a lot of mileage out of the 32 smoothing groups, by recycling them.

sheckee

Thanks Mark!
For the most part I'm fine with smoothing groups, this is an example of where I ran into the problem.



I want the red line there to be hardened. Really I'm just wanting to make a lowish poly model to mess around with some hand painted texture practice on. Nothing special. I just wanted to give myself visual 'creases' under the cheeks here, around the nostrils, the lips, the eye lids, and the breasts. I think using multiple smoothing groups it is probably possible; just seems so long winded for something I can do in other software packages by selecting those 3 edges and hitting harden.

phixel

What about using crease amounts when in edge selection mode? I am unable to see your linked dropbox images due to my firewall at work, but by increasing your crease amount on a selected edge will harden it similar to adding a chamfer. Might be a useful alternative?

sheckee

perna wrote: »

Jon, I strongly suggest you depart from that line of thinking about switching between software. If you try to work the "Maya way" in Max, you'll be at a significant disadvantage.

Work the Max way in Max.

Yes, it's a tiny bit faster to do that specific thing in Maya (are you really going to miss those 5 seconds?), but having smoothing groups with a large amount of unique IDs as opposed to simple on/off states for edges in Maya is so much more powerful.

You won't be able to take advantage of the extra functionality if you're still thinking the "Maya way" when working in Max.

About your specific model: For such a simple case, I'm sure the above script will work perfectly fine. If you wish to do it by hand, simply use different SGs on each side of an edge for it to show as "hard", and the same SG for it to show as soft, it's not more complicated than that.

I am trying to depart from that line of thinking; at times though, the only way I can describe what it is I want to achieve, is by describing it based on previous experiences. If that makes sense? You are right though, smoothing groups are very powerful and I do enjoy using them. I just have to figure out how to use them to my advantage in every situation.

phixel - creasing is a good shout, I'll certainly have a look at that too!

I'm really just trying to broaden my tool knowledge in 3ds max as I've been using it at work for quite some months now, but I've only learned what I've needed for my job.

sheckee

Cool stuff, I really appreciate your help on this, Per.

JamesTKirk

I can't think of what can be done with smoothing groups that is impossible with hard edges.

ALSO
There is workaround in 3ds max to control hard edges:
In editable poly turn Use NURMS subdivision on.
Set iterations to 0 so it won't actually subdivide geometry.
Now crease spinner controls hard edges: 1 means hard, 0 means soft.

Converting object to editable poly again will turn NURMS off and automaticaly set
smoothing groups.

Farfarer

JamesTKirk wrote: »

I can't think of what can be done with smoothing groups that is impossible with hard edges.

Stuff like this...


Not often you'll need it, but it is very hard if not impossible to do easily with edges.

JamesTKirk

Yes, you are right, I didn't think of this. But these special cases are better managed through direct normal manipulation.

Mark Dygert

Two points:

1) Often my models have normal maps and the smoothing is all in the same group, sometimes one group per separate object if there are multiple objects/elements.

That doesn't mean I don't use smoothing groups, I do. I just don't use them for smoothing, heh.
A hard edge on a high poly is often too hard and I would rather crease or bevel the edge so it appears sharper, but it doesn't break unnaturally. If I need to blend a break, I do that with support loops on the high. The smoothing from the high poly overrides all smoothing in the low poly so I don't really care how the low poly smooths as long as it doesn't change after baking.

2) I use them to easily select faces and when unwrapping I will explode by material and smoothing. Then before baking I assign it all to 1 group. Sometimes if I have multiple objects they each get their own smoothing group but everything in that object is in the same group.

ok a 3rd point...
I have used the hard edge script in the past, when I was doing low poly only work but I haven't bothered to install it in the last 2 versions of max.

ok a 4th point...
In the butt example above, even if it was only a low poly I would throw another set of loops in there, not only to control the smoothing better, but to help with deformation. I would gladly take them out of someplace else if it really affected the tech budget in some major way, I think it won't in most cases.

sheckee

Wooa, cheers guys! This is really helping a lot actually; it seems the smoothing groups are more powerful than I previously thought. I'll have to start keeping these points in mind. Really grateful, thank you everyone

JamesTKirk

perna:
Thank you for explanation, it makes sense.