Maya to Houdini Transition Guide | Robert Magee | Houdini Hive Worldwide

[Music] all right next up we've got Robert McGee hey Rob hey Chris how's it going good how you doing good good thanks so we're all working from home yes that one for you excellent yeah it's just focused on the screen so to get things done so what's your talk on today well I'm gonna talk today about transitioning from Maya to Houdini talk a little bit about sort of the muscle memory things you've got to go through that the little changes and the concepts and ideas that are different that you have to wrap your head around in order to make that transition so you've got a bit of a history with Maya yourself yes yes I actually I worked there when I worked at alias way friend back when maya 1.0 first came out and worked on some of the first tutorials for maya back in that in the day and so it it's interesting to bring the worlds together and to talk about them as a team Maya and Houdini can work together through Houdini engine yes yes that'll be part of the talk as well just the way that you can use it any engine to put Houdini digital assets right into the Maya environment and then our artists can be taken advantage of Houdini without even realizing is there all right well let's let's jump in wooden board ooh okay thanks Chris welcome my name is Robert McGee and I am the Senior Product Marketing Manager at side effects one of my key roles is to manage online learning paths for you Dini artists and to create educational material such as the Houdini foundation's guide today I'm going to talk specifically about transitioning your Maya skills to Houdini many studios use both of these applications and production it is a great idea for artists to be proficient in both of them it is said that the second application you learn can be the hardest but once you see that there are areas of common ground it will make your transition easier there are of course differences and we will explore some of these as well we will also talk about loading Houdini digital assets right into the Maya interface where the Houdini nodes and networks will be cooked under the hood this is an exciting way of working with both these applications together in one pipeline but more on that later first a bit about my background with Maya during the 90s I worked at alias research which then became alias wavefront a subsidiary of Silicon Graphics in case you don't know alias wave friend is the company that created by a long before it was purchased by Autodesk I was involved with Maya when it was first being developed and helped offer the learning Maya tutorials that shipped with version 1.0 going down memory lane like this gave me an idea for this talk using a workflow that was introduced 22 years ago and learning Maya we will work with these two applications side-by-side to build a political space ship model this process will help you discover how your knowledge about the interface modeling texturing animation and rendering tools in Maya can be applied to working in Houdini there are a lot more similarities than you think and that is a great place to begin bridging your skill set from one world to the other here we are looking at the workspaces for Maya and Houdini side-by-side they look very similar they have a main viewport in the center they have a shelf tools up at the top they have transform and select tools down the side here and this gives them a very familiar look as you move from one to the other there's a number of options display options sort of at the top here in the case of Maya down the side here in Houdini so little shifts but mainly the same thing now let's use the Shelf tool to create something ready let's create a cube in Maya and you can zoom in and take a look at that similarly we're gonna take and make a box in do you need this time though you've got to press the Enter key to place it at the origin otherwise you're gonna place it down yourself now let's take a look at the view tools it's always important part of learning and application and in Maya you are used to using the Alt key too with the the left middle and right mouse button to tumble track and Dolly and in Houdini you can actually use the Alt key for exactly the same purposes so from a muscle memory point of view that'll be pretty straightforward now you can also use the spacebar which is similar for people who are coming from let's say Adobe also if you click on the View tool you actually don't need the modifier you can just use the the mouse keys so you can set up for views in my if you want to look a planned section and elevation sort of thing and you can do the same thing using that little button up at the top there in Houdini now once you're in there you can just the spacebar to zoom out or spacebar B and Houdini to zoom out and you can go back and forth so you can go in make another view go back another view all with the spacebar similarly you would do the same thing in Houdini now attribute some parameters so when you put an object into a scene you get a bunch of attributes available in this attribute editor here in Maya and in a case of Houdini we're just gonna pull off the side we have what's called the parameter pane so in who do you need to call parameters in Maya they're called attributes attributes turn out to be something a little bit different in Houdini I'm not something you'll learn down the line now accessing tools we we did use the shelf but in the case of Maya you can also use the marquee menu here in this case you can sort of take that marquee menu and dock it here on the on the view you could also go in and say you know what I want these polygonal tools and I'm gonna dock those here as well so they give you the same tools up in the shelf but you have them here to work with now go to do the zoom tool and I'm just gonna move that in so we'll move that across and they won't use the same thing to make a Taurus and we'll just move that up over uses a little square thing to move it along the plane so now we have three objects within our Maya scene let's go and do the same thing in Houdini so in Houdini we're gonna use the radio button you press the C key and we go down to levels where we can now pick from this menu and pick fear again it doesn't place it we have to present enter to place it and then we can move it let's say over here just like we did in the other case and now we're gonna go do the same thing get a Taurus in this case instead of placing the Taurus at the origin we're just going to click to place it now if we do it here we use the view plane we turn on this construction plane there we can actually make sure we put it on the ground there it is on the ground so don't forget the construction plate if you want actually build or move things right on the ground so transforming objects is important thing working with a 3d application so in the case of Maya you can transform or move things using the W key and I allow you to move things around you can press the E or two key to get rotate and then rotate the object around or R to scale and these actually are conveniently laid out on the keyboard wer are right up there with your left hand now before we gonna do that with Houdini we'll notice that we whereas in Maya we can freely select the different objects by default in Houdini should clear selection is on what that means you have to press the S key every time you want to make a new selection or you have to turn secure selection off that little lock that I just turned off there and once you've got that we can have hotkeys in Houdini for move rotate and scale as well in this case using T R and E again in more or less the same location but not the exact same keys as Maya this is probably one of the biggest muscle memory things that you'll have to get used to a lot of times you know you might press W in Houdini and end up getting in wireframe mode when you were trying to get moved so just remember it's T R and E now I want to go back into tumbling and generally speaking a 3d application the tumbling sort of works around the center of your view and that's sort of what's going on there in in Maya in Houdini there's a new tumbling where the pivot gets set based on what you're clicking on so as you can see I can get three completely different tumble pivots depending on where I'm clicking now this comes from this option here keep pivot would would actually if I sort of home the view it doesn't matter where I click it's always going to sort of use the center of the of the scene so a little bit more like what Maya has or we can use this set pivot and the real benefit of the set pivot sort of comes if you were like way off from the center or the origin and you're trying to work on an object you can now tombola round that object even though it's not near the center where things started so that can be beneficial but if you want to be a little bit more like how it is in Maya you may want to just change that to the key pivot another thing that we've got in in Houdini which is new worth pointing out is the new pan and scan so this is where you can actually zoom in and out of the view but you're not actually dialling in and out your and literally it's like your pan and scanning the view you can control click to go back to normal and switch back to 3d but if you're in a situation especially if you're in a camera you might want to lock that that view to make a creative decision that's available so let's get rid of these extra objects where don't need those to create our spaceship and let's get zoomed in back onto here now there's another tool the handle tool which we've got that here so it's the T key gives you the manipulator in Maya and that allows me to set in this case for this box the width and the height and the depth and so on for for that box you're actually controlling the the main node that creates that that cue now in the case of edenia if I go to the handle tool you look up at the top bar and I get pretty much the same kind of control so I can go in with the sides and say 0.7 0.7 and I get the same result now it turns out that I'm what's happening here is Houdini has a couple different levels and if we go back to say just to the node view you'll see there's the object and if I dive into it I can see the Box node and that's where I've set those values but even if I'm I'm back up at the object level I can see those values and when I'm down here and the handle to was on I actually get handles specific to that node that I could manipulate here in that view so that's that's exciting too and most nodes in Houdini of some sort of handle that you can work with so selecting components so if we click on this right now we're selecting the object but we want to get at some of the faces of that object so we go into component mode you can press f8 for that and then click on faces and if we click on there we'll get that one and there we get that one and we can tumble around it we've now selected those two faces and we're gonna use those in a second before we do that lets go into Houdini so if I'm up at the object level I can click on this second one here and go primitives faces are called primitives in Houdini and I can go in and select this face and that face and you can press f8 to go back and forth in Houdini as well or you can press four to jump when you're in the Select tool will go down to face selection so using the shelf we're gonna poly extrude this out we're gonna zoom that in and I've got this nice handle here which lets me you know to various scaling and moving we use that to start our shape here now in the case of Houdini we've got our selection and we're going to go in and under again we use the shelf poly extrude now we get a different kind of handle here we're not getting the nice transform capabilities there turns out that we have that but that's not the default in Houdini so what we're gonna do is we're gonna click transform extrude front gives us the handle and we're gonna make that the default so when we do this several times throughout this tutorial we we all we we don't have to switch every time we're always going to get the one that we want so now we can take this transform handle and that allows us to pull out we can press the e key so the same hotkeys that would apply to transformations that the object level would apply to doing it here with this tool so the next thing we're going to do is go back to Maya and we're going to keep doing this so this is a box up modeling technique so that means it's going to be a whole bunch of manipulations primarily poly extrudes and we're gonna use the G key to repeat the last tool and that's going to allow us to we did that twice to get us to scale down and then to scale out to get the wing and we're gonna go back into Houdini we're gonna do the same things we're gonna use Q to repeat that which allows us to create the wing here Q again and in this case we'll make that a little like this press T to bring out the transform and push that back and there we've got the same result so in the one case we've got G to repeat and the second case we've got Q so just a important note now if we take the top piece here again we'll press G scale that in G push that up just Cal that in and push it back a little bit we can keep doing this there's a whole bunch of different shapes that we're gonna want here with Polly Cruz let's get them all done here in Maya and then we'll go do them all in in Houdini and so you know when you're poly modeling often you'll just do a lot of pushing and pulling of this nature and in this case we're actually going to use something a little bit different we're going to use this offset here to inset those faces and then we can press G G again and then we can push them push them back so we get a nice clean even offset around all the edges and then that can be pushed back now we're gonna go look at the same thing in in Houdini so again we're going to keep pressing Q allowing us to do the kind of things that we were doing that we were doing in Maya pull that up push that back do the same with the front and bring that forward press e scale that down just got that across maybe push that down a little bit get nice little nose there now we're gonna do the the same sort of exhausts pieces that we did in in Maya so we're gonna go select these exhaust pieces and this one and we're going to inset them so instead of offset that we had in Maya that's called inset here in Houdini and then we repeat push this back and because we had faces on both sides it did it in both of them and now we have the models in the same place so now we're going to explore the different ways of viewing the models and this involves sort of wireframe shaded so in the case of a Maya breeze for to go into wireframe mode five to go into shade there's also a couple others for going into textured and so on but we won't we weren't worried about those two later the case of Houdini we just toggle back and forth between wireframe use the W key to go back and forth you've also got these little buttons here at the top in Maya and you've got this little menu here we can do a whole bunch of different options beyond just their smooth shaded smooth Y or shaded got a bunch of different options there now peligro models set themselves out really well for turning in the cells into smooth subdivision surfaces and so here Houdini has one for rough two for medium and three for smooth in the case of of Houdini you've got to go shift + to turn subdivision display on and shift - to turn it off and this corresponds to if I go back up to this object level here there's a little menu display as and as I turn the hot keys shift + if I go shift + you'll see that I turn display as and turn it on and off so that that's really what you're setting with the hot key in that case so you can actually find it and do it by hand if you want to or we can go back down here and there we have our smooth version now in the case of Houdini it only goes down to a sort of the cage display which is sorta like the medium option in Maya but they both give you a smooth look but instead of doing it with sub DS we're actually going to smooth it using in this case we use mess mesh smooth I set the subdivision to two and the reason we're gonna do that is we need the extra polygons so smoothing is not subdivided it's literally breaking it down into more polygons and we can do the same thing in Houdini so we select all of that and we're going to do that with if we go to the poly tool we can just scroll with the middle scroll and then we get the subdivide and we set that to two and we get the same result so in these two cases we're not dealing with subdivision models we're dealing with smooth or X adding extra polygons now let's say we like the shape but we want to you know we want to be a little bit more creative with it and so we're gonna throw a lattice on in in Maya we do that here and we would set divisions of four two and six and that will give us enough control now once we do that we then go into component mode on the lattice so we not phases but rather points and then we can start to select different pieces of this and manipulate it and this will allow us to create a generalized reshaping or deformation of what we've been working on and this will allow us to you know make creative decisions on the overall shape so we're gonna go there grab these points edit that maybe shape that up a little bit now we could do this by going back and playing around with the poly extrudes but you know this gives us a nice sort of you know way of working with the final shape and that doesn't quite we want maybe I'll just get that blast a little bit there bring that down bring that out bring it down a little bit more and there we go so now we've got a little improvement to the ship tweaking to how we want it to look now we can do the same thing in in Houdini so we can go in here press n to select all the geometry in this case the faces now we click on the deformation lattice tool now we still have to press all the way it asks us to select the points even though we have the faces before us we had to reselect them and then we press ENTER a couple times because we don't want to put our own cage around it and we get this one now if we click on the lattice node okay in this case here we use one number less so instead of four two and six between three one and five gives us the same cage now we take that and we can again sort of essentially go into component mode on that by selecting the points and then we can start moving that cage around and we get a you know the same result that we were getting in Maya so here we go now in this case here we want to move it so we're gonna move it up and back a little bit and then just like we did before let's grab that nose and we're gonna pull that forward and maybe push that down a little bit so again you know not exactly the same ship but but the process of getting us where we want to go pretty much the same now if we go up to the object level you'll see that the cage the whole interface for the lattice goes away because all that's happening inside at the what they call the geometry level in Houdini and that's so the history of it is sort of buried inside that object in the case of Maya the original the geometry that makes up the lattice is actually part of the scene and so even at the object level or at the top transform level there's multiple things to select as a matter of fact if I was to grab that spaceship and let's say let's move that out you'll see that the lattice doesn't come with it and it gets all mangled so the way to solve that in here is we can parent those two lattice pieces to the cube and now as we go forward that works out well and if we don't want to see the lattice we can select those two things and press H to hide them and now we can get the spaceship looking pretty much the same way we have it here in Udine e so in one case that the things that make up the history of that of that construction live often at the object level whereas the case of Houdini they're all buried one level deep so let's take a look at what's going on under the hood we sort of peaked already what's going on in Houdini both Houdini and Maya have node-based workflows in the case of Maya you have nodes with attributes connected the case of Houdini it's nodes that are connected it doesn't need a specific connection between one parameter and the next to work now we can bring up the hyper graph panel here for the one in Maya and we can go and take a look at that and we see essentially all of the things that we were used to create that and those represent all the tabs that you saw in the attribute editor that people in my off and use those attributes those tabs to go through and change the construction history of some object so you wouldn't really admire generally go to these nodes and select them to make changes and sometimes to clean things up a lot of people in Maya will delete history so that when they go back to the attribute editor it's like the object it's all cleaned up they don't have to worry about all those extra nodes they're happy with where they got and time to move on the case of Houdini there isn't really the same concept of deleting history what I'll often do in Houdini instead is let's say I will add a null object here at the end let's call that spaceship out even though all the nodes you know seem like they're you know maybe don't get complicated in some cases and some models you can do things like put them in network boxes like this collapse them clean up the model a little bit and and the history is not really you know you're not paying a huge price for the history because of the way that Houdini is structured once it cooks once you're pretty much good to go so you don't need to go through a lot of deleting of history but if you really want to lock things down if you do not want those nodes above to affect the outcome one option here is to freeze let's say that no object and everything that's feeding into it is locked at that space there so I could go up and change one of the nodes feeding into it it wouldn't change this is the result but I can if I want to make changes I can unlock it and then I go back and do this and one of the nice about Houdini is I can select these various nodes in here and if we turn on the handle tool that's probably the wrong one right there but if we we see the cage as it stood at that point so each time you select a node you see the cage that's specific to there and the handle that's specific to that particular node so we can go through and continue to tweak and of course in Maya you could have done that if we kept history around you could have used the parameter pane to make these same kinds of edits but it's really nice the way Houdini actually lets us see the cage and manipulate it right there in the view you can even set the display flag on any one of these nodes and jump back and see where the model was at that at that particular stage if you want although it is nice to have the display node here at the end and then just select and manipulate those nodes along the way now another thing that sometimes people do to lock down geometry rather than freezing a node is they will save the geometry to disk one of the avenge this is it makes it a shareable item that you could share with other scenes and use in other contexts so I can create a spaceship bgo file save that to disk except and then I'll just put a file note down and bring that back in that can feel a little weird at first like you're all the construction history is gone but it's what it's doing is it's saying I want to have a lockdown version for whatever I'm going to do next but I'm going to keep that that node network around in case I want to make a change I can always re-exported or change it later and it because the final node is referencing is off disk it's a live connection so so the next thing we're gonna do is add a material so in the case of Maya where we're adding a standard material adding a texture map and of course we don't see it yet because we forgot about the other display which is for six I believe and that allows us to see the texture Maps and if I bring up a UV panel what we see is there a UVs on the cube originally and well not much UV work was done after that so we're gonna have to fix that in the case of Houdini we're gonna do this by bringing opening up this panel bring in the material palette and putting principal shader on there and in this case we're gonna make that white by default because we're gonna text your map something it's always good to have a nice clean because that a gray would get multiplied in and we bring the texture map in and assign it now in this case you don't see anything and the reason is because Java tree and in Houdini does not come in with UVs at all so we're essentially only seeing the first pixel of the texture map and if we go in and set the UV view up and because we've assigned a material we can actually pull off of this little menu select the object pull off this menu and say background you can see it off the side there but we can say pick that texture map so we've got the same thing in both cases in one case we have the UVs from the cube the second cases we have no UVs and so we're gonna fix that by doing some planar projections now like I said this tutorial was for 22 years ago there are way better ways of of setting up movies in both Maya and a new Dini at this point but when you've got a pre-built texture like this this is this is probably the good way to go for now we'll keep it honest to the source material and use the planar projection so you can you know play around with the different settings in here and in the process of doing that get yourself the look that you want and sort of line that up and as you can see down below the the geometry is lining up with the texture and this texture was sort of designed to just project through it's using simple colors and just projects right through the cockpits probably showing up at the bottom of the plane we could fix that but we won't do that here today but we could easily fix that if we wanted to so there we have the the texture map applied to there now there's no sisal logo in the corner if we wanted to we could go and get rid of that sorry not get rid of that we can go and assign that do another projection in that area and then we can just use these handles to scale that down and reposition that so we can scale that down and then move that up to here and I think we're gonna flip it right around and you know a very interactive way of doing this kind of thing and what we're doing here in Maya we're going to do something similar in Houdini although a good UV flatten probably would have been a better way to go and paint the texture after the fact in a 3d paint program but for what we're doing here again honest the material will do our projections so here we have the Houdini one and we're going to go to the textured thing and UV project is sort of the that's the equivalent of that select all the UVs and we project that on and just happen to sort of be in the right place to get what we wanted there get almost a similar look to what we got in and in Maya and then if we want to do the fin with the the star Solaris logo we can do that as well so we're gonna go in and select those faces and again do a UV project but first we're gonna convert them to vertices that way because we can't project onto faces and this one didn't come out quite the same way so we're gonna need some parameters to do some tweaking on that just like we did with the one in Maya we have to do some orientation on that and fix that up and so on and we could use the rotate tool and where we just set the parameters and go from there there we go we're bringing that across and there we go we get our starburst more or less doing what we want in there get a little more tweaking so make sure it's all read there and today got it so in both cases we were able to take the ad UVs on to the geometry that was done in the case of Houdini if you go back down to the geometry level you'll see that both of the UV projections created nodes here that would allow me to go back and tweak and in the case of Maya there are two tabs up here which means that there's nodes somewhere in the hyper graph representing those actions as well so these is where the two are actually very similar and if we were to export a bgo and Houdini we'd get the UVs and the same if we deleted history in in Maya so let's do some animation we're just going to do a little bit of simple keyframe animation to just show how that might be a little bit different between the two applications in the case of Maya you're going to take that spaceship and you're going to press the S key to set a keyframe move forward in time and then move the object forward and time do a rotate rotate that a little bit off and then you press s again so every time you make a change like that you're going to press s unless you have hot Auto key on which is not by default we want to get another key somewhere in there press K sorry press s s in Maya spoiler alert K is gonna be the option in Houdini and there we go so we got some keyframes on that going forward and we can bring up another panel and if we want to set that panel to a graph editor then we can see the curves that are resulting from from that motion and if we wanted to do some tweaking you'd do that here in the graph editor and you could you know move that around and in time and and and in in coordinate coordinate and there you go and scrub through to just see what that edit might might accomplish okay now back in in Houdini we're gonna go and set those keyframes as well we're gonna go find the initial position at the transform tool press the K key like I sort of said before or you can use that little key button down there on the timeline but essentially you can bring it forward press K set a second key now once you've set the key you can actually make modifications without setting K again and it will pick those up so as long as you're lined up with a key you can make anything that's got an animation channel on it you can make an edit and there we go so we get basically the same animation here that we had and in Maya and if we want to see animation channels for that there's the animation editor now I could I could have setup panels top and bottom just like we had in Maya but there's just there was a quick tab there that I was able to quickly go and grab it and tweak I could also pull this off and put it on a second monitor if I needed to we haven't talked too long about the different tabs in Houdini but there are a number of different UI elements on the different tabs which are worth taking a look at so now we're just gonna render this and in the case of Maya we're gonna use Arnold and in the case of Houdini we've got a couple different options and we'll talk about about how we're gonna do those but let's first set up what we see is sort of our nice shot so near the tail end of the animation with the spaceship banking here let's get that set up and ready for for our shots so in the case of setting up a shot what you want to do is you want to set up your camera now it turns out we're already looking through a camera in Maya the person camera we can add more but we can work with that one as well and we're set up the resolution gate to get a sense of what that's going to look like when we render now we created a camera here in Houdini which also shows us the render solution sort of thing and we can you know if we were to go and make it you change here you'd actually lose that camera because like I said we're not in that camera so if we lock it with that little lock then we can make view changes and it holds on to that camera now for the rendering we're going to go and take this and before we do anything we want to put a light in let's just put a distant light ten it's coming from some distant star and we don't really see any effect on that because there's another level of display in Houdini and we have to go one notch higher and that's above five hotkey five will give us some lighting so we can see the effect of that here in Maya and we can add some intensity to that light and there we go ready to go now in the case of Medini we can do the same thing just go and get a light here we're gonna get a distant light just plop it down here in the scene and we can already see that how that's affecting the object and we can go and create that look that we want right there that gives us more or less the same thing and we get serve a higher quality display on there as well if we want to see some of the specular highlights that would happen on the spaceship now we're gonna render the current frame here in Arnold and there we go we get our rendered out version of the spaceship and we can now do the same thing in Houdini using the mantra' render mantris been around for quite a while with Houdini and we're gonna set up the display options for that and then we're going to render in what's called em play and this goes runs through it and we ended up rendering a little higher res here instead of 960 by 540 we're doing the little higher res here and you can see how that goes through now you'll notice a lot of Jaggi lines on there we're rendering the polygon model and we have that sort of happening in both the cases now to render is a subdivision in Houdini the way we do that is that display a subdivision wouldn't be enough there's actually a little check box here render polygons a subdivision and if that has to be checked if you want it to render as subdivisions so now if we go and re render that to M play you just see as that runs true we're getting a much smoother result it works at the micro polygon level so even if we zoom in really really close you're not dealing with tessellation or anything like that you get a nice result now the other option Houdini is a new section of Houdini called Solaris or lops for lighting operators and this is USD based and it allows us to bring in scenes from other parts of adeney or from from a USD file it creates a USD scene graph out of it which you can manipulate and organize to potentially export out later for rendering and has a built-in Hydra render called Karma which is sort of the the next-gen version of mantra which works nicely and interactive here in the view and we can do things like play around with the intensity of the light we can tumble around you see we're getting much faster response than we were getting with mantra now if we go in and we want to I know let's say crank up the metallic on that a little bit go a little crazy with it we get a nice cool look like that and then we can go in and just go back to here we can play around with that light a little bit more maybe crank up the intensity that light even more and in addition to tumbling around the view we can also play around with in time moving forward in time and stays relatively rendered you know for the simple scene that we have allows us to sort of evaluate things quick and easy so Solaris lops is sort of the future of this karma karma render is in beta right now but it is the next gen beyond mantra and it is worth they can look at an understanding we are now going to talk about the Houdini engine for my a plugin this is a technology that takes interoperability to the next level and makes it possible to put Houdini under the hood when working in Maya this way some artists can use a Dini without even leaving Maya's interface before we get started let's explore how this works in Houdini you build nodes and networks that define a procedural flow of data these notes can be collapsed into a single node called a Houdini did gelasa or HDA which contains the original network inside this asset is stored on disk as a HT a file that is available for sharing a high-level interface can be built by promoting parameters from the nodes inside to the top level these can be renamed to make them more artist friendly the HDA file can then be shared with another artist working in Houdini to them it looks and feels like any other node in the Houdini interface and the artists can focus on the top level UI and doesn't have to bother with the nodes and networks buried inside this asset can be shared with multiple artists in a very robust referencing scheme such that changes to the assets can be easily propagated to all of the artists on the team this provides a very powerful way of working it allows artists and TDS to build custom tools without relying on coding that work reliably in a production setting while this procedural asset works well for teams in Houdini artists what about artists using other applications such as Maya one would assume that opening an HD a violin Maya would not work and out of the box this would be true but if you have installed the Houdini engine then the nodes and networks would get processed or cooked by the Houdini libraries being called on by the plug-in and just like with Houdini one asset can be referenced in to multiple Maya sots creating a common toolset for all artists in your pipeline Houdini engine plugins are also available for other apps such as 3d studio max cinema 4d or game engine such as Unreal and unity but to really understand what I'm talking about let's go see how it all works so here we are back with Houdini on one side Maya on the other and we're going to start in Houdini by creating a cube and then we're going to shatter that cube to make a whole bunch of smaller little pieces now this creates a network here at the geometry level which includes a couple different nodes one of them here is chunks Enders where we could determine how many pieces we're going to shatter that object into now what we want to do next is sort of expand those pieces out so we're gonna put a node in called exploded view and we're gonna place that down and there we go we get a that we get the ability to either see that as a piece that's together or as a piece that's that's that's shattered so we can go in out using that slider there let's go to point 5 for now so we've created a simple Network where we've taken one object shattered it and then we have the ability to explode that object up so this is a workflow that it's a procedural workflow inside Houdini and we want to take this and bring this into Maya so the way we would do that is we're gonna start by creating a digital asset and this digital asset is like I've said before we're gonna save it on disk I'm gonna put it into the folder and we're going to give it a name explode shape accept and then we should probably give the operator name make that something similar so explode shape and press accept so this is a file now on disk and well this panel will we'll come to in a minute the key is we want to go over into Maya and load this in now we can't see the Houdini Engine menu over there so I already pulled it off so that we could quickly get at it but normally there'd be a menu up at the top says Houdini engine after you've loaded the plug-in you can't make sure you load the plug-in so we can bring that asset in and put the menu off to the side and there we go now we've got the same result here in Maya but it's sort of a static object at this point we're not getting any of the procedural benefits because we don't have any control and as you can see we don't have any control here in DNA either up at the top level so what we need to do is we need to build that interface by promoting up so let's bring up that exploded shape and this interface here is where we can take parameters from inside on the nodes inside the asset and promote them up so in this case we're talking about the number of pieces so we can actually call the parameter number of pieces because that's what we're doing so we can have a more artist friendly name here at the top and then we can bring this uniform scale up and we'll just call that explode scale that way it matches what we're doing now when we press accept on that we basically saved all of those changes those parameters to disk but just to make sure we're gonna save it there now to get this to get the parameters on that we've got a click on the exploded shape one that top-level there and then the attribute editor will display the information about our asset and we can reload the asset and what you'll see is right over there are that are the parameters we just created over in Houdini so we can increase the number of pieces we can play with the explode scale and what's happening is every time we move a slider in there the Houdini engine plug-in is going off talking to Houdini the Houdini libraries making the change and bringing the results back into the host application which is in this case is Maya so we want to continue to do some things so one of the things we're gonna do here is we're gonna add an input here because one of the things is right now we're doing everything on the sphere we created a Nutini we'd like to do is be able to apply some of the things we're doing onto objects within the Maya environment so we're gonna add a switch node here and we're going to feed that input into the switch so this will give us two options the box or something from the outside world how does that work well here in Houdini if I was to put let's say a torus here outside of the asset then what we would be able to do is feed that into the asset and it would become essentially that second object that we could play with so we bring that in double-click in and if we to go to the switch node we'd go back and forth between the torus and the box depending on index 0 or index 1 and so that's great so that input is going to be important when we bring it back into Maya before we do that though we need to add it to our interface we need to make it something that we can work with them because that switch is going to be important once we set up the asset so we're gonna take the selected button we're going to drag that on here to create and we're gonna give it a more friendly name let's call it shape oh it's called shape so what kind of shape we're gonna use well the first option zero is the box answer and then one index one the option is custom shape so we're either gonna use one or the other and we press accept and if we go up one level here you'll see there's that menu in Houdini on the asset and we can switch between those two and this now that we've saved this on disk we should be able to get that same capability over in Maya so let's just make sure we've saved that and should be good to go now over in Maya we've got to again reload the asset and now we got a option for a set selection so that's the input number one that we set up earlier so we've got a piece of geometry here it's a model of a human skull and we'd like to shatter this object and then have the ability to explode it so we select that object here and that fills in the information there let's hide the original model and now we can take this and using the shape no parameter we can switch between the custom shape which in this case is the skeleton and then we can play with the scale or get in there and play with the number of pieces so there's the ability to set up an an asset in Houdini that will act on things objects and so on within the my environment and that's very important because these tools are gonna be much use for you in my if they can't interact with the things that you're working with in in Maya so we'd like to take this a couple steps further we'd like the ability to move this thing around so we're gonna add a transform node and we'll by default let's move it up a couple units and maybe have it rotate a little bit because we're gonna get set this up we'd like to also add in the ability to do a little bit of a dynamic simulation set up the simulation in Houdini built into the asset so that it can work in both Houdini and in Maya and we had a bullet solver geometry node right here and we plugged that in and we set the display on that and there's a couple just different options here one of them is set up a ground plane and that will allow it to have something to collide with and gravity is already set ready to go and press play and so there we have our object falling and if we want to we can create a custom shape and that falls and we're good to go so again if we want this to be usable we want to promote some of the parameters so we're gonna take the transform node and let's go in and add a separator just you know to tidy up our UI now we're gonna add a translate and a rotate allow us to move our objects around oh they went in the wrong order let's just fix that notice how I'm building this you I would just click and drag I'm not writing any code so an artist can literally be building their own tools that's pretty exciting so we come down there's those parameters there in case we want to control that and when we pressed apply we basically saved the asset so we're all ready we're good to go we can reco reload the asset here and we notice that it'll work because we're gonna see the good a little more thinking with the skeleton and it's good now it's not quite I think if we want to put this a little higher I'm going to put that up and if we press play we should get a simulation of this falling and colliding now this is a more complex piece of geometry than the one we were using inside Houdini so it's a little slower but it does catch so once you do that you can scrub through and the one thing is notice it's coming in green and I'd be interested to find out what's going on there that's where maybe the help bar down below might be be useful so if we go in here and play we see there's a little warning in the morning it certainly is something about an attribute called VAR map and that might be causing the problem we have there there we go data type VAR map so again if there's something going on we can quickly go back take a look at the asset see what we can do to fix that so we're gonna put an attribute delete in here and that will allow us to find this VAR map attribute which they call I think it's a detail attribute but let's check if we click there there's a detail attribute called VAR map so we can go there select that delete that boom so in order for that to be stored we need to save the asset and then we're going to have to come back into into Maya and reload the asset or re hit reloaded now once we reload it because that attribute that Maya was not happy with is gone it'll rebuild and we should be in better shape yes we gone back to normal display and we're not dealing with we're not dealing with the whatever that green color was the warning color so now we can take this our skeleton and press play and we have taken an object from Maya we have shattered it explode it the pieces out and run a dynamic simulation on them all inside an asset that is running Houdini in the background with the Maya environment and this is what Houdini engine does and this is how all of the tools that you have available new Dini can become available to people working in Maya using this exciting Houdini engine technology now that you know how the Houdini engine plug-in works let's take a quick look at the different licenses used to run the plug-in depending on your chosen Houdini product let's start by looking at someone running both Houdini and Maya on a workstation in this case the same commercial Indy and Education license is used to run Houdini can be used to run the plugin inside Maya this is good for artists going back and forth between the interactive package and the host application you will note that Houdini apprentice licenses cannot be used to run the plugin now if you're running Maya on its own on a workstation then you need either a Houdini engine for commercial assets or the free Houdini engine Indy for Indy assets education also has access to engine licenses but again apprentice does not for processing scenes on a farm or in the cloud you use these same engine license types be sure to note that only three Houdini engine Indy licenses are allowed for studio therefore only smaller farms are supported by Indy we started today's talk reminiscing about a tutorial written 22 years ago now let's talk about how you are going to learn Houdini today to get more tutorials you can go to learn getting started on the side effects website where you find the foundation guide including this overview chapter and many tutorials created by side effects and members of the Houdini community there are also a few more transition guides that offer different approaches to converting your skills for Maya to Houdini and a number of learning paths covering a wide range of topics it has never been easier to access quality Houdini tutorials and I encourage you to keep exploring thanks for joining me today good luck on your journey and I hope to see some of your amazing artwork posted on the side effects gallery in the near future

Channel: Houdini

Views: 5,049

Rating: 4.9268293 out of 5

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Id: z0S3bGeQMIE

Length: 56min 33sec (3393 seconds)

Published: Fri May 22 2020