Mantra Tutorial — Principled Shader - Getting Started Course ep. 03

hi welcome back to arise works and in this third part of the workshop on getting started with rendering shading with mantra in Houdini I really wanted to talk to talk about principal shader what a principal shader is what it does why does it have so many tweaks how do we define material as a metallic or nonmetallic what's the difference how to make start making glass materials how do we make things emit light what's what's what's roughness stands for what it does and basically it's a bird's eye overview of the principal shader now why is this essential because I think we will be using around 95% of all new materials that will apply to geometry therefore understanding how the principal shader works is essential to building materials and making things look like the way we want them to look without further ado let's get started hello and welcome back and I think in this video we will try to figure out what principal shader is what it does and how it controls our material and basically we will be using principal shader for pretty much every material that we will create later on so it is important to understand how it works and how it operates all right so now I will just hold down the control key and press the greed and I'll create a sphere and I'll just in the objects in our object context I'll just hold down the Alt key and then drag and drop and create a number of spheres so on the Left I'm gonna have spears that's our nonmetallic on the right that's our metallic but don't don't think about this right now we'll figure out as we go okay so we have the perfect layout now it's a matter of actually moving these spheres around okay they Spears I'll just of them so the left's to the right okay so back to our materials I'll go to the material context and as you know you can add the principal shader by right clicking here and go to the shaders and let's click principal shader or you can press the tab button and then start tapping P R and C and there it goes you just press the answer Enter key and again we have the principal shader which is pretty much two ways of adding materials okay so I just want to have this principal shader let's say it'll be I don't know let's say orange okay I'll make a copy of it again I was holding down the Alt key over option key if you're on the Mac and just dragging drug dragging and dropping and it creates its a copy alright so this one will be roughness of 0.1 so what roughness does is it defines how polish the surface of your material is for example the polish plastic has roughness of 0.05 like this or maybe 0.1 so the smaller the number in the roughness and by the way it goes from 0 to 1 the more reflective it becomes now IOR stands for index of refraction and usually IOR is used for explaining how the refraction of the transparent objects will work so effectively IOR represents how dense is your material less IOR less refraction of the transparent objects but we will talk a bit about later so I just want to showcase you how roughness effects the materials so the material I'm sorry principal shave their number one and I'll just name it gloss see okay I'll drag and drop on this one principal shader three let's call it medium and principal shader four let's call it rough okay so medium let's say roughness point two around that and rough let's animal 0.7 okay so this I will drag and drop on at least sphere and the final one I'll drop in there I'll drag and drop on the final spear so as you can see I will now just add a at the lights so we can see the reflections a bit better I'll control click on the arrow light here control click on another area like here and it this should give us a better representation of how the lighting scenario go as we can see our lights on the rights and I think the exposure is a bit too much okay tweak a bits the exposure and there we go by the way I just want to make the grid of it larger okay this looks fine so as you can see already if we just zoom in in the our viewport and we make the materials and the lights look a bit better by clicking these different icons as you can see it's a high quality lighting and this is a normal lighting and this headlight only and we can also go in a flat mode so for now I think with the high quality will be just enough as you can see on the left of the glossy one I'll go back into the materials here we go this our glossy as you can see when I change the color it changes the color as well so it doesn't blur out the reflection the middle one has the reflection bit blurred out and the most right one everything is blurred and we can see that you know the light is being blurred throughout the whole surface and let's just see how it looks in the render view preview let's give it a couple of seconds to think about what's in our scene and as we will see in a bit aha there we go so the most left one has almost perfect reflections the middle one has a slightly blurred and the third one everything is blurry and it looks kind of rough right and this is how the non method work so the main difference between metallics and no metallics is that usually the first of all to define metallic or nonmetallic it should usually be either 0 or 1 anything in between will look more or less incorrect unless you're going for some specific or stylized effect just to be safe usually all non metallics like plastics glass and other things they have metallic value of zero and everything that is metal as the value of one so the main difference between metals and nonmetals is that nonmetallic materials they have the diffuse color as you can see in our case it's orange the diffuse color and they have the reflection that is not tinted whereas metallics virtually have only seen that reflection and no diffuse color so let me just showcase how it will look it did if if it sounds a bit confusing I'll just again select all the three old hole the old key I'll just drag and drop and make a number of other copies and it remembers the difference in the roughness the middle one is slightly rough the right is very rough now what I'm going to do now oh by the way somehow I forgot to turn off the metallic Ness okay so let's fix it I'm sorry for that we'll take just a second okay now if we get this matt'll slightly rough metal and very rough metal we will see just what's what's the difference I was trying to explain about the diffuse color and the teen's color so basically metals only have the reflection and the color of reflection is the team that has the base color as you can see here we have orange sphere but the reflection is is how it is is just white whereas here we don't see any color but we only see the reflection with the colorized with a color that is mainly directed by the base color okay so let's let's see how it will work with slightly blue version of these set up so this is our nonmetal and this is our mantle I'll make the same blue ish but this one so as you can see our action has been tinted into another color and by the way as you can already see here in our top left sphere we can see the reflection of the blue ball after our blue sphere and the reflection is non tinted blue whereas on the bottom ones which are our metallics we can see the reflection has been tinted and the blue ball reflects as a green one same the reflection of the most rough sphere on the right is getting reflected and tinted by the reflection and it's becoming green as well here as you can see we do not see that on the top one because on the blue ball the reflection is still yellow so hopefully that explains a bit about the difference between metals non-metals if it sounds a bit confusing trust me it will become better over time when you kind of get a bit more experienced in that it will all make sense it's just you know don't think about this right now we will create different materials further in the course so you'll get enough experiences to I figure out which which is which which settings do we use or any type of scenario okay so now that we know what roughness and basically the base color and metallic does reflectivity is something that is a bit more CG ish because you can you can decrease the reflectivity but it will not be very much realistic by the way I will now hold down the shift key and drag select this amount of my viewport so it computes only here because we don't need to compute the whole scene we just want to see what's going on here so as you can see if I decrease the reflectivity despite the fact our roughness was very low and it should be shiny we do not see any shininess at all so when I bring back to reflectivity you can see right yeah okay now it has the reflections but if I decrease the reflections it becomes well it looks kind of strange basically so this is not really realistic and you should not basically use that if you want this type of effects I would suggest instead going for the full roughness which will give you more or less same effect but as you can see it will be slightly tinted by the rough reflections from the it's fear from the right so it basically it will look more real and you can decrease the IOR which will again decrease the amounts of things that are reflected so now that we talked about the IOR I just wanna I just want to say real quick a couple of things about this thing so if the IOR usually it's one point five right so it can be lower it can be higher but usually do not tweak this unless you know what you're doing and tweaking the IOR I'll just make the roughness point three and again I'll start the render to showcase what's happening when we tweak the Iowa so I are actually stands for like as we said before index of refraction and basically it usually controls if we have transparents like things like glass or water is something and it controls the refractions but on top of that it also controls the the reflection on top of refraction so the more you are value you have on your material the more reflective angles of your objects become so if the IOR is really small you can see it it is reflecting only the angles that are looking directly at the camera and if we increase the Iowa it starts to reflect so much more from so many more angles than just from the angle that happens to be from the camera from the camera view okay so what I'm trying to say is for example if you have a material that should have a rough reflection a blurred reflection but for example it's like a stone right a it's kind of rough but it reflects a lot and we will we will see about that later on I'm just trying to explain all of these things I will showcase how it later on how it affects your reflection but just keep in mind this stands mostly for how dense and how heavy is your material in the layman's terms RK just without this industry fraction like reflection whatever basically these controls how dense your material is the denser it is the more refractive and reflective it will become even with high values of roughness okay finally there is this transparency and subsurface scattering mean that we should stop and talk about so transparency as the name suggests it makes your things transparent right as you can see it's immediately turned into class and subsurface scattering makes it appear as sort of a material that can be penetrated by the light to some degree for example like wax on candles or human skin so if we enable subsurface that first of all it becomes a really noisy because subsurface needs a lot of samples to conversion to look better and let's say we need this to be really really red and the distance point to will work so yeah this this is really noisy I think we will discuss subsurface in further videos I'm just trying to go through all of these different apps all in one go and I'm sorry if it's a bit too much information that at one girl but this is the overview alright so bear with me okay so the distance suggests how much of the distance is being penetrated by the by the light and of course it's in the cadena distances Dini system so one is actually really really lush okay I'll just hold down the control create a camera I wanna I want to just show you how much one really is so as you can see we have this negative 19 and negative 18 so this represents one and hour our spheres here should be with the radius of one as you can see uniform scale one it's the radius of those so if we have the subsurface with with the distance of one it means that the whole sphere will get penetrated by the light so tinker with this a little bit and see what fits your material and yeah that's the subsurface scattering okay next one I will showcase using the material palette I'll go here drop a red red velvet's for example I'll drop the red velvet's on our blue ish sphere and velvet's as you can see it appeared here because we got it your palate I'm sorry and as you can see the roughness is one the RR io RS 1.5 the base color is dark red and yet we have this thing that is called shin that says 5 now what is supposed to be doing is imitates the sheen of of the soft cereals like from the clothes from the sweater kind of thing from Dino sweatpants and stuff like that maybe from even your codes and what have you but machine that is being built in in the mantra is kind of slightly problematic and possibly I will show you what does it mean and how to work around the limitations of the mentorian because for the most part it's it's noisy and when you try to fix the noise or increase the shin it becomes even worse and it's very hard to control so I will try to show you how to control how to fake the shin using other technique rather than increasing this one so if I make the shin at zero I'll just left-click on this snap so we can compare with different results of the render you okay let it converge as you can see it's ever so slightly more lights especially on the angles that are not directly looking at the camera okay so that is shin again not very recommending using it in mantra because it's a bit problematic and as a final thing instead of I will not cry no actually I will create L just hold down the left the alts left mouse button drag and call it a missive now I will just enable the emission color let's say we want to have this pinkish to be emissive and I'll drag and drop on the sphere again and it should be amazing this color now before you actually do the emission or anything it will tint it with the initial base color let's say if we have like green as you can see the dark green is being overlaid by the emission color so it kind of has a worrier teen here and there so effectively if you want to make zero tinting on your emissive you can go either black or white black usually makes it you know stand out like it's just amazing things so as you can see it's being reflected as emissive in other in other spheres so that was a mission okay and the final thing would be the opacity now the opacity it's not to be confused with transparency because transparency is is being used for things like glass or things like what's uh I don't know you can make a transparent vase or something whereas the opacity is actually just controlling if the material is rendered or not okay I'll just create another another copy of our material and colet's opacity:1 zero okay I'll drag a drop on this little spear okay so now that it will start rendering the second okay [Music] all right so if we start to decrease opacity it will start just to fade out it will not be actually transparent as in imitating the effect of glass of water or something but it will just become more transparent I mean sorry opaque and it will just fake the effect it will just not render it at all if we have the opacity of zero now you might be thinking well this is a really strange where do I even use this and this is used when you have a texture of opacity for example for for tree or other vegetated leaves or other vegetations because usually the Leafs on the trees are not actually modeled with of geometry but they have a simple polygon with the texture that looks like huh let's see it looks like grass or it looks like a tree leaf and it just makes everything that should not be rendered opaque and it actually starts to look like a leaf and I think we will showcase that as Paul later on so finally let's just see what we have a new texture table basically we have any textures and we will talk about that later you use the texture you you tell Mantua where to get the texture and it will render the texture on the sphere all right so again you can see that it has base color are you our roughness pretty much everything that we have here but with texture information that you can paint in marine or substance painter or somewhere else we have the bumpin normals to control the micro details which will which we will cover as well displacement which will move around your actual geometry to create additional detail again we will stop on that I later on and this is just you know you don't need to even look there so there you go there you go I think the most important thing that you should understand about making materials is that first one of the most important things is base color roughness metz a likeness and the normals more bumps we will talk about normal slater so these three or four channels control mostly how your material looks and we will start building our own procedural materials using different masks and color information the noises later later in this course so yeah play with the principle chainer try to understand how it works tweak different things see how roughness works how metallic is different from nonmetallic maybe you can create some interesting-looking geometry and make make it transparent so it kind of you have a fancy base or something and yeah see you in the next video thank you for watching hopefully you liked the video and the whole workshop we have a lot a lot more to talk about so hit the like button if you like what you see and hit the subscribe button if you don't want to miss anything else that will be in the workshop going forward don't forget to leave comments if you have questions suggestions or any other ideas I'll try to respond accordingly and so don't feel shy leave the comment below see you later and have a nice day [Music]

Channel: Arise.Works

Views: 13,486

Rating: 4.9883723 out of 5

Keywords: houdini, rendering, mantra, tutorial, free course, materials, principled shader, metalness, ior, diffuse, tranparency, lookdev

Id: 9lIIGhUM4hE

Length: 26min 49sec (1609 seconds)

Published: Sun Nov 03 2019