From the course: 3ds Max 2021 Essential Training

Art directing 3D map parameters - 3ds Max Tutorial

From the course: 3ds Max 2021 Essential Training

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Art directing 3D map parameters

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- [Instructor] In the last movie we created an OSL Uber Noise map and connected it to the Bump channel of this paint material. Now let's art direct that Bump Map and achieve a stucco noise effect. In order to improve performance I'm going to disable realistic mode. I'll go into the viewport menus, to the shading menu, and set Materials to Shaded Materials without Maps. And additionally, I'm going to disable automatic update of the preview for the material. And that way the only thing that will update will be this map preview. Right-click on the material preview and from the pop-up menu disable Auto Update Preview. And now we get a little slash through it, circle with a slash meaning no preview unless we manually update. Let's see what this looks like in an actual rendering. I've got ActiveShade all set up, so click ActiveShade on the main toolbar. And this is a very subtle effect. Let's get in really close in the viewport, click in that view to give it focus, zoom in with Control + Alt + middle mouse, pan with the middle mouse button, and get in real close on that wall. So we do have a Bump attached, but it's very, very subtle. So let's increase the intensity of the Bump. Select the Physical Material, scroll down in its parameters, in the Special Maps roll-out increase the Bump Map amount. I'm going to crank that up quite a lot to a value of five. And even so we really don't see a lot of Bump here, it's a very subtle effect. But once we adjust our Uber Noise parameters we can make that much more exaggerated. Okay, as you may remember, Arnold can only update in one window at a time. So to see an update of this Uber Noise preview sample I'll need to close the ActiveShade. Let's go into those Uber Noise parameters. Select the Uber Noise node and at the top of the OSL Map Parameters is the Noise Type. From that pull-down list let's choose Worley Mankowski 4. And our sample kind of blasted out, became almost completely white. One reason for that is this Step Function per iteration parameter. So the noise is made out of multiple iterations or layers and on each layer the Step Function is adjusting the contrast and brightness. So let's turn that off, disable Step Function per iteration. The other important parameter that deals with how layers interact is the Combination Mode and it's set to Add by default. Each layer or iteration is adding to the one below it. Let's switch this over to Multiply and now all the layers are multiplying with one another, and we see a sort of cell pattern in our preview. In the Noise Settings we've got the Base Wavelength, that's the size of the first iteration or the bottom layer. And if we reduce that size, bring it down to let's say five, then we see we've got a smaller pattern. All right, I'll set that back up to it's default of 25 for now. This Worley Jitter parameter adds a little bit of extra chaos. I'm going to increase that a little bit, I'm going to set that to 1.5. Then we come to the Fractal Noise set up and the Number of Iterations, also known as the number of layers. As we increase this by integer values we will get more layers or more iterations, each one smaller than the one before it, as determined by this Iteration Frequency Ratio. So that is the size of each layer relative to the one before it. If we set Iteration Frequency Ratio to a value of two then each layer will be half the size of the one before it. The parameter below it, Iteration Amplitude Ratio, is the strength or the intensity of each layer relative to the previous one. That has no effect in Combination Mode Multiply. It works in Add mode, but not Multiply. However, if we wanted to we could edit this map, we could change its fundamental behavior and make it so we could edit the code of this map so that Iteration Amplitude Ratio worked in Multiply mode. And to do that we would go up to the top of the parameter editor, in the upper right there's a magnifying glass. Click that button to launch the OSL code editor. And within here we could actually change the fundamental operation of this map. Of course, that's out of scope for an essential training course, but if you're interested in creating and editing OSL maps I covered basic OSL syntax and technique in my weekly series, 3ds Max: Tips, Tricks and Techniques. All right, I'll close that code editor window and go back to the Uber Noise parameters. There's a section down here labeled Layer Distortion and this is going to distort the shape of each iteration. And right now it's got a pretty strong Amount, but a pretty low Scale. So to see this effect I'm going to increase the Scale, set that to a value of one. That Scale parameter is the scale of the layer distortion relative to the Base Wavelength scale. Setting Layer Distortion Scale to one we can see the distortion pretty clearly here. All right, I'll bring that back down to a reasonable value of let's say .3. Then there's the Scale Ratio, which is analogous to the Iteration Frequency Ratio. The Layer Distortion Scale Ratio is the size of the distortion relative to the iteration before it. So I'll bring that down a bit too. We'll set that to 0.6. And reduce the overall Amount of Layer Distortion to a value of two. For a stucco effect we'll need more detail, so we can increase the Number of Iterations. Let's bring that up to a value of eight. And now we've got a kind of grainy look. In this case I'll also want to increase the Base Wavelength. I'll bring that up to a value of 50. And I'm pretty close to the effect that I want, but I want to invert these colors for the Bump Map. So I can swap Color A and Color B. Click and hold the mouse down on Color A and drag it onto Color B, release the mouse, and from the pop-up menu choose Swap. And now the Bump Map is mostly white. I do want to control the contrast of this. I want a Step Function, but not per iteration. I want a Step Function on the overall output. So enable Step Function output and let's set the Low value to 0.1 and the High value to one, its maximum. And if we disable that and re-enable it we can see that we're basically brightening up all the dark parts there. All right, so we basically have what we want now. I've art directed this effect and we can see what it looks like by doing another ActiveSahde. Okay, we've got a pretty exaggerated stucco effect here, but I wanted that to be pretty strong in order to make it visible for the demonstration. For a final production rendering I would probably want to go back to my Physical Material and use a more reasonable Bump amount, maybe bring that back down, set that to a value of two or something. That's how to art direct the parameters of an Uber Noise procedural map.

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