Creating an aiStandardSurface material - Maya Tutorial

- [Instructor] Arnold provides a very thorough suite of materials and maps. There are many different shading nodes for various purposes but the workhorse is the Arnold Standard Surface material. If you've worked with physically-based materials before, the Arnold Standard Surface should be pretty familiar. In this course, we're going to cover the basics of the Arnold Standard Surface but in all honesty, we could devote an entire course to exploring its many features. I've got a scene set up for material testing. I've created an Arnold Skydome with an HDR map to provide environment lighting. In the perspective view, go into the Viewport menu and choose Renderer, Arnold, and then start the interactive production rendering. This is a good setup for testing materials because we'll be able to see reflections of the environment in the surfaces of objects. We can see that if we tumble or orbit around with alt and left mouse button, we're actually seeing reflections on the surfaces here. If we just used ordinary lights without an environment map, there would really be nothing to reflect and the surfaces would look much darker. That wouldn't give us a good idea of how the material would look in a completed rendering. To prevent the visual distraction of a background, I've set the camera visibility to zero in the Skydome attributes. We can select the Skydome, go to its Attribute Editor with Ctrl+A and down in the Visibility section, I've set the set the camera rays to zero. We can increase that to a maximum of one and see that in the Viewport here. Just want to illustrate that I'm using a monochrome image so that the hue of the lighting is neutral. We don't want colored light while we're testing materials. We'll bring that camera visibility back down to zero. Close the Attribute Editor and open up the Hypershade window. Now I've somewhat hotrodded the Hypershade and I've kind of stripped away almost everything. You'll see that I've hidden the browser. I've also hidden the create panel, the bins panel and most importantly I've hidden the material viewer. We're using the Viewport here as our material viewer and we don't want to have the material viewer open at the same time. It won't even really run unless we have a full version of Arnold installed. Another point I'd like to make about performance in the Hypershade is it's a good idea to have swatch rendering disabled. If I go into the Window menu and display the browser, you'll see that I've got swatch rendering disabled. The button on the upper left of the browser is turned off and that will prevent Arnold from trying to work too hard to update swatches and it'll devote all of its energy to updating this Viewport here. Let's close the browser once again. Now let's create an Arnold Standard Surface material. Don't confuse that with the newly-introduced Autodesk Standard Surface. Maya 2020 introduced a new physically-based material list designed to work with other renderers, not just Arnold. And we'll find that if we go into the Hypershade Create menu to Materials, there's something here listed and it's called Standard Surface. The Autodesk Standard Surface is essentially a clone of the Arnold Standard Surface and it's been made renderer agnostic, meaning that it's compatible with other physically-based renderer. If you're rendering in Arnold, it won't matter which one of these you choose. But in this course, I want to use the Arnold Standard Surface so that the course is more compatible with Maya 2019 and 2018. So in that Create menu, I want to go to Arnold Shader Surface, Ai Standard Surface. Click on that to create the node and its shading group and we'll want to rearrange the graph to make it visible. And maybe zoom in a little bit with alt and right mouse button. Navigate with alt and middle mouse button. So here's our material node. Let's rename it in the Property Editor. We'll call it, "ideal diffuse aiSTSF". Press Enter and then select that string of letters and copy it, Ctrl+C, select the shading group node and paste that in, adding an "_SG" at the end and now the shading group name matches the material name. I want to start by creating a so-called ideal diffuse material and that's one that has no specular component and it reflects all of the diffuse light. I want to start with that as a baseline test material to verify that my scene lighting is exposed correctly. So now we've renamed that, let's assign it to all the objects in the scene. Go up to the main menu and choose Select, All then right click near the top of that material node and from the marking menu choose Assign Material to Viewport Selection. When that assignment's been made, let's deselect everything, go back to the main menus and choose Select, Deselect All. Let's adjust a couple of key attributes. Select that material node and in the Property Editor increase the base weight to its maximum of one. That's the strength of the diffuse component and if it's down at zero, all we're getting are shiny highlights. Let's bring that up to its maximum of one. We want to make sure we've got a white color. Click on the base color swatch and just verify that it's got no saturation and a value of one. For an ideal diffuse, we don't want any specular components so reduce the specular weight down to the minimum of zero. And if we tumble around with alt and left mouse button, we can see that it's not quite bright enough. For this to be exposed optimally, we would want this to be actually white on our screen and it's looking kind of gray. That tells me I need to increase the exposure of the environment. Select the Skydome and in the Property Editor increase the exposure to a value of one. That doubles the amount of light and now our ideal diffuse material is rendering as white. That's the basics of how to create an Arnold Standard Surface, assign it to objects and create an ideal diffuse material for testing purposes.