Smoothing geometry in Arnold

Bhaumik Patel
A free video tutorial from Bhaumik Patel
Experienced 3d artist and instructor
4.3 instructor rating • 8 courses • 17,623 students

Lecture description

In this lesson you will learn detailed information on how to smooth your geometry in Arnold.

Learn more from the full course

Maya 2017 - Create realistic images using Arnold renderer

Learn the fundamentals of Arnold renderer by rendering a realistic scene in Autodesk Maya 2017

03:21:37 of on-demand video • Updated February 2017

  • Render realistic images using Arnold renderer inside Maya
  • Use the different light types in Arnold
  • Use the aiStandard shader to create wood, glass and metal materials
  • Use the aiSkin material to make cheese and grape materials
  • Use the Arnold render view to troubleshoot and diagnose renders
  • Know how to use the Arnold depth of field controls
  • Know how to use samples to reduce grain in an image
  • Use sets to smooth objects at render time in Arnold
  • Use displacement in Arnold
  • Use textures and optimize them using tx maps
English [Auto] In this lesson we'll take a look at how to smooth out objects and the parameters to do that. So you can see that these grapes here a little bit chunky and we need to make this nice as well and the cloth as well. And anything else would like to smooth. So the way to do that is you can use standard my way you can select this and press three and it will update and it's just that region. So you can see these kinds of småland and these guys don't have a press wand here. So it's not made press three. It is. OK. So that's with a mile away. And that means that your objects are going to be smooth in the viewport as well. And that's generally not used in production because you basically want to have control over some of these parameters in terms of smoothing. And also you don't want your scene to be really heavy so that you go a whole city for example and you want to smooth most objects then you don't want that to be seen inside the viewport because it slows down the seat. So what we need to do is we're going to just add a little. We're just going to adjust a little parameter in the shape note and that will tell Arnold to smooth this at rendah time. So let's just do on one of these cheese pieces because it's nice and easy to see some of this going to bring up my on are going to be here as well on the side. And you can see I'm already in the shape note here. So this is actually here in the shape note. And then we're going to come down here. The section and subdivision. OK. So if you change this to nung this is what it looks like. Space this morning here. Again none like this. And then if I can turn this on camel clock it's going to smooth that out and all that's going to do is going to subdivide. This is going to split each face in half. And that set by this so if you want it to be split further you can increase this and make it even smoother. It's going to become tighter and it's going to have more polygons. Obviously the more polygons you have the slaveries to render. It doesn't affect it too much. In this case because it's quite small object but just bear that in mind. So you just want the minimum that you need to get the nice smoothing effect that you want. OK. So it's going to put spiked at one and we're going to use a diagnostic mode with this screen to change this to debug shading and will change just to wireframe which is really cool. So now you can actually see just tenths of a second. You can actually see the polygons and what you're getting. OK. So you can see here that this object is smooth. So it's got more coated gums and you can see that here compared to this one. So it's quite handy to see what's going on here. So if you look at this you can see it's split each face into half and then it's smooth the shape in. So if I were to change this to Linnea you could see the polygons. But it doesn't actually smooth them because it will smooth the normals so you can see the normal edge does not appear hard anymore. Whereas before when it was like this it appears hard. OK. So that's the type and most of the time you're going to be using a clock of course because you want it to be smooth through that one smoothie. So let's just move the grapes here. So I'm just going to press one on this great object. It's not smooth. And then we'll do it the old way. So I'm selecting the grapes it changes to Catmull Kronk and then we go is smooth once. So I could do this again to this grape object here. But if you're doing multiple objects and say you've got 10 different objects this is a bit of a pain to do each one separately. Now you could use the attribute spreadsheet which is in Windows 10 editor's attribute spreadsheets attributes spreadsheet say Windows where it says that hey I've been using you attribute it to the attributes spreadsheet so in here you would look for a parameter you could type in here and then you could adjust it. But instead what we use is an override set. OK. So that's just simply a Maya set and well that's going to do is write a bunch of objects at the same time. So if we just select this scope to select this guy and this guy and I'm just going to create to set Sigger to create that and then you can go to the options if you want to rename that and look at the father. Now some would say apply and now we have our set. It's just put the two objects inside. OK so now we just need to tell that set the thing that we want to change. So you select it you can see there's a section in the set. And then you can add parameters of the things that you'd like to overwrite. So if you cook them at He's got a bunch of different attributes here that you can overwrite including on of ones. So it's sometimes difficult to know which one you need to override. So the easiest way of doing that is to actually just come in here. I open up the script editor here just press this button here and then all you do is you just come down here and just change this to none. For example and you can see that the attribute that's changing is a subdivision type ball sub div type or sub div type. And so we just need to add that to our set. OK. So this clears it up and grab this guy at and then come down to a nice do type that we all on at and then because it's up so I can see inside the extra attributes section we now have that control. And if it's just opened up the window here. Changed this to what we do need to add a subdivision number as well. So let's add that. Well it's going to add this to. So subdivision iterations. There you go. Let me update the scenes just up this scene. We've got to give it a notch. So there you go so I can see if the trend is to not. Then up that is in the kitty has an effect. OK. So now you can control multiple objects at the same time and you can control the amount times it gets subdivided as well. So it's going to turn that on and just change that to something like an to see the difference. OK so now let's go ahead and. So that's how you move multiple subjects at the same time using over sets so just have a look at the math here. It's moot as well. Just change that to a clock and maybe just change your attitude and see what that looks like. I'm going to change it from the deep shading to disabled so you can see the difference there. So just change up back to the back and we'll have a look at some of these other parameters here. So just changes to life. And again we can actually bring up that ones that disappeared because they crashed in between. So if I show showed de-bunk shading I can change it quite easily to shading and then my friend whatever I want to. OK. So if we go to the tablecloth here. And that's been playing around with it so we say numb you can see it's not divided. And then if I change to Catmull clock you could see it's divided and you could change the iterations here. But just changed to zero. Just so you get the same result. So this is what you get iterations to smoothing it twice so you get the admiral polygons and you can see that. Typically if you're using something like a ground plane you generally want to have more polygons of the front and then don't necessarily need to have lots of polygons at the back so it will save you rendah time and memory. If you do that especially if you've got displacement applied to your ground that so on and provides ways of optimizing this and it does this to adaptive metric. This is thing here. OK. So you can actually set in here. When it should subdivide. So I'm just going to change this to three. So you get quite dense mesh there and then as you slide this adaptive era up you can see that it removes polygons so you can see it can subdue already here. And then it's going to subdivide it less at the back there. OK. It's quite sensitive. So if we just bring this down that suit is better again. 0.72 and you can see these ones again these polygons are getting the maximum amount of smoothing and then these at the back are getting less. OK. So you got to be careful with this because what this can do is if your camera is moving this can look like it's popping because it changes while you're moving the camera. So in order to stop that you can actually use another camera different camera and can type a name here. And that camera can be kind of in the same position maybe the start position or the end position and then you can just put that name in here. OK so it will use that for deicing icing is when it splits this polygon up into some polygons. So instead of using the the main camera or use another camera and because that camera is not moving these politicians will not pop. OK. So that's quite handy. So that's what that does. And this adaptive metric is in two different forms you've got excellent and flatness. So excellence is what you use when you do displacements. So this is measured in pixels so you say this changes edge length and you make it bigger. Ergo Finally you can say now it's going adaptively less and more. OK. This is the one I use most of the time. And this diagnostic view is really handy in terms of seeing what you're getting. So the whole point of this is to get a nice rendah that looks nice but it doesn't take ages to render because it can take ages if you add lots of polygons. The last two parameters here are for movies moving and they've got different ways you can do with your UVA's whether he's moved them or whether the keep the borders. And when you just made them that linearly these are the same parameters that are in your regular smoothing. Then you've got smooth tangents and this is a really handy little tick box. If you go and see trophic highlights things like brushed metal for example and got long thin highlights. Sometimes they can appear a little bit Steffie if you turn this on they're going to be nice and smooth. OK. That's quite a nice little tip that because sometimes the big product Gwenda's and you can't get rid of this kind of stuffing and then you increase the settings on the on the anti-aliasing but you still can't get rid of it. This is this is the thing to turn on. This does use more memory but it's worth it if you want to get rid of that stuffing of course. So in this case it's pretty small sex. So I'm not going to use adaptive I'm just going to change it right down. We're going to get the full effect. To do whatever you want to. By the way auto setting will use etch that is displaced and flatness. If it's not OK. So in this lesson reviews and I right set to smooth our grapes and we've got our nice smooth and smooth the tablecloth and that was using the on the crepitus here. They also actually got to smooth the stems here as well. So let's just quickly do that scrub the stem here. And just add a couple clocked around between that to America. So let's save all see there.