Introduction to Houdini - Chapter 7 - Making a chair

hello everyone and let me start by saying happy new year and for those of you who might watch this much later so this is I'm recording this on 1st January 2018 and I decided I'm going to be productive on the first day of the the new year that doesn't really mean anything I might not be productive for the rest of the year but I kind of figured ok I'm going to be productive for the first day of the year and I'll make a tutorial and you can be productive by learning something new on the first day of the year at least the ones of you who are not like hungover or sleep-deprived from you know whatever revelries you were involved in last night but for the rest of you yeah you can study a little bit on the first day of the new year ok so I wanted to make the chair because I've given that as an assignment and some of you have sent me files I sadly haven't looked at them I will but I kind of figured but a few of you also asked in questions because you've sort of gotten stuck in some places so I figured I'll make a chair tutorial as well and since we had covered a few things in the previous lesson like groups and add I'm making a little making it a little more complicated so what I have is we're gonna take a look at how to make a normal chair and then how also we can turn it into like a circle that looks weird but you can make those adjustments later but just to have you know like to change inputs and get a different result so we'll take a look at how to make how to make a more complex procedural object or it so let's get started so I just create a new file and we'll start off by making a simple table ok so I'm just going to take a piece of geometry and let's delete this and I'll create a grid and let's start by you know making a basic grid of one by one and this I'll keep it 2 by 2 yeah okay so let's get started so I'm just going to take a line tool okay and now what we had seen last time was when we try to do a copy we do a copy two points and because of the normals on the grid the line comes in and sort of lying down so what we can do is we can take an add node and if you delete the polygons the normal sort of don't cause an issue anymore so if you just do delete geometry but keep the points you'll notice that the lines go back up again so we will do that okay so let's take a transform in the middle for both of them so this will be the line height or let's call it the leg height and let's take a transform here and this will be my let's call it base size okay so this is the basic and then we will take another transform let's call it sighs okay so we can just make it slightly bigger you know so I'll just press E and kind of make it you can't see it hold on a second yeah okay so as making about one point one in both x and y what you can do is if you wanted to be uniform size you can copy this parameter and paste it here but we don't always wanted uniform size so you know like in a chair you wanted right chairs are usually not stretched out especially like if it's a single person thing then it's squarish so you can copy paste this here but that's optional okay and then you will take a transform to move this up so I'll take a transform here and I'll take the leg height so we'll do copy parameter and y-axis paste relative reference and merge these together and that gives me my basic you know table as what I had before and then we'll put a poly extrude in the middle to give it some thickness yeah okay so that's my basic table that I have okay now comes the second part which is I want to create the back for this okay so in order to create the back I am going to split it from from here itself so we want to do like two things right so my basic hold on saying this is to be so this is my basic you know table with four legs and what we want is something like this at the back and like this so this is what we want to generate so what I want to do is I want to generate you know like these two things at the back and this and then sort of move it back over here so like we the idea is to create it in the center and then also give it like a little bit of rotation so that we can tilt it and then have it move back to wherever we want it so what we're going to do is we're going to take the same four points that we have here we had done grouping in the previous lesson so we're going to group these two points and the first thing we are going to do is we're going to move these to zero you know so I'm going to like figure out a way to move these to zero and then scale them down a little so they're in the middle and we can copy like two lines on it so those that will become the you know the the sticks for the back then we we branch out the basic table and maybe like like that is my basic table the basic grid and then we can like squash it a little and that will move to the height of these lines okay so we take the whatever the height is and put it in a transform so then this will move up here like that and then finally we will figure out a way to move this back to location now the reason why I am moving these in the front here is that it it is more convenient to make everything at zero if I like if I don't move these back these lines will be copied you know at these points but then this grid will have to be moved back so either and then the rotation becomes a problem because the rotation pivot usually comes at zero then we'd have to figure out a way to procedurally or you know mathematically move the pivot back here so that'll cause additional issue so it is better if we can just move everything to zero place everything here and then push it back so it's a little bit more work but hopefully that will work out and once we have done this much like once our basic back is done it will move up to the height of the legs plus the thickness of the table so we are going to take this height plus this height okay so these two Heights will have to be added together so we'd have to do a slightly longer channel reference in like two stages so we'd have to do something like channel extrude height or just height plus channel you know leg height so we'll have to like add those two together to get this to the right size to the right height okay so let's get started so what I'm going to do is firstly I want the the legs to have a different height for the back so we'll take a second transform and we will call it let us call it stick height with HD okay and what I want to do is I want to separate points from here so we have you know these four points you can switch on the point number so you can see them better and what I want to do is let's say I want to take one and three or let's say if we take it this way then we want like zero and one okay so let's take zero and one so we'll take a transform what sorry we going to take a group first of all we'll take a group and I'm going to create a group out of these two points and we will have 0 and 1 make sure you change the group type points because by default it's kept two primitives there are no primitives here so you won't select anything so make sure that this is kept two points so we have done that much I'd also delete whatever is not required so let's take a blast and keep it to group one and say delete non-selected so we'll have like zero and one the next thing we want is I want this here you know at the centerline so just so that's fairly simple you can do it in two ways I'm going to take the simplest method is you can just take a transform and in the z-axis scale it to zero and that'll work as well if you want there are a couple of like you can also do it through coding like then do it through Beck's but I'll cover that when we get to X like I don't want to do that right now so we'll just call this move to zero and let's also take take a transform because you want it to be you know like slightly inside like right now this is exactly like at the edges so you wanted slightly inside so we go to squash it a bit so just press E and scale it down so let's take it about point eight so we have done that much now I can take the the back sticks that we have take a copy two points and just you know copy these two things so there you go so where they are right now is right in the middle okay see that's where they are okay so this is done sorry yeah that's done now we also want to create this thing a table so now we also want to create the back okay so let's take our transform I'll pick it up from the base size and the first thing I want to do is I'm going to take I'm going to press key and scale it down Riddle and then we'll also take another I'm giving all the movement separate you know just so that it's easier to know what we have so let's call this as back size and we will call this as rotate 90 because they're supposed to rotate 90 degrees and then we'll rotate at 90 in the x-axis okay and then the last thing is this has to move up to this height so take the the back height here we'll do right click copy parameter take a final transform and in the y-axis space relative reference so there you go and we can merge these together so that's 1 & 2 and then I can take a poly extrude and give it some thickness and also come down and turn on output back because you know otherwise the back will be hollow I think we might have to do that with the yeah with the main table as well yeah output back okay so this is done like we have the back and we can take the whole thing and rotate it slightly after the merge so I'll just you know like come in here if you can't see the handle just press Enter like you know come in the viewport press Enter if you press escape it will go back to navigation mode and so if you just press ENTER it will come back and just tilt it a little bit okay and then we need to do a final merge but before that we also need to move it up so like we have the back and this and finally just take a transform again and now as I said we will have to do like to channel references so first pick up the leg height so we'll do copy parameter let's call this move to top and we'll come to the y-axis and do pace relative reference and just selected press control C and then we still have to move it back so I'll just I'll do that in a minute but since I'm doing this let me continue with this okay and then we also want this height you know the thickness of this so come to the poly extrude let's call this something so we remember it's a color table thickness and take this distance values to do copy parameter come move to top and then paste native reference and then do a plus and paste the previous one and there you go so now the final thing left is this has to be done before the merge is we need to move it back so what we do is we take like these two points that we had where other points yeah zero and one I want to take one point out of this and or actually before the transform so yeah so like you know these two points I'm going to take yeah I'm going to move this out like if you want to detach it just shake it so it detaches and move it above that okay so so that it scales before we move it to zero I want to take one point out of this like delete the second one and move that in x-axis to zero so just take take a blast like branch it out from here and we're going to delete delete either one so we'll delete one and yeah it usually it says guess to group guess from group so since there are there is there are no polygons it'll automatically know that its it has to be points but otherwise if you want you can keep it two points like either ways is fine and then take a transform and it's going to be the same move to zero like what we're done there was that axis here we need to do x-axis so just taking the X scale and move it to zero see so that comes to zero and then take another copy two points and move it back so they even okay so if we hold on not there this is the rotation so this has to come beforehand yeah so now if we merge everything together see so we have our basic so this is the let's call this back rotate and so if I take this see so the advantage of this is like since everything is at zero it's easier to rotate otherwise let's say we've already moved move this on top then the pivot will have to be placed in a location where you can then rotate it and that will require little more of like you have a type of few more variables to do that this way we don't need to do that so what we have done is we first took you know two points from here move those to zero in the z-axis so we could copy the lines and then we took like one point out of those two points and just instead of moving them in the front we moved it in the x-axis to zero so that maintains the back location and then we can copy the entire back to that location okay so the advantage of that is that if we adjust the size here you know like the base size then the whole table will see the whole table will automatically adjust yeah this is the problem because you know this same base size is going into both places so when I scale it down you can see the back also scales which is not bad actually you know like you might like that we can also address the back size a little bit so it's wider okay one more thing that we can do before I get to another point which will be more complicated let me just take the table thickness I want this slightly thicker is as I had said in the previous lesson you have some tools that can create groups automatically so let's say if you want to bevel in the tops okay like we have these and I want to make you know give them a little bit of wrongdoing or whatever then we can take a look at that okay so what we can do is let's say I want to round these a little bit anyways because this doesn't matter like all the copying is done through the add this is just for you know the basic extrude and you know giving it thickness so what I can do is I can take a poly bevel and if I take a poly bevel on just you know like this basic grid and I can drop it in there and it will bevel the corners so if I just take the poly bevel which by default goes to edges so we will keep it two points and you can increase this see and you can keep the shape to round and give it some rounding so it looks nice so then the table will look you know a little bit rounder if we look at the final merge see and I can do the same thing here like I can take this do control C control V and just drop it in there anywhere should be fine and then what I want to do is I want to Blake bevel the top so what I can do is come to the table come to the excel the poly extrude and you have this option down here which says front group which is this particular polygon so I can create a group okay so if I come in here and press information you will see that it there is one primitive in the front group let's call this call it something small and I call it f and then I can take another poly that'll drop it in after the table thickness select the F group and we'll give it a little bit of beveling and a little bit of rounding so yeah so there you go and we can do the same thing here so we can take the poly extrude and do the same thing just to extrude let's call it f as well and I can take the poly bevel do control C control V and drop it there if you want it for both like front and back I can come in here and I can we can also create a group for the back so we'll say F and D and we'll do the same thing here so legs let's do F and D okay and come to poly bevel and just update that and type in B as well so it will do front and back see this is the nice thing about having groups and not doing manual selection is that if you want to make additions to this you can always go back and make additions and the nice thing about this is this is not like it doesn't care about the geometry count which is the best thing about it so if I come to the poly bevel and I increase the number of segments you'll see nothing goes wrong because it's just selecting the extruded front face automatically you know like the same thing here if I come to this body bevel and increase nothing is going to go it'll still work so yeah now here's the last thing it looks a little rounded because that's a problem with with the normals and the faceting so what you can do is as a final thing I can take a facet or you can take a normal you know let's take a normal and we can drop it somewhere okay let's like let's drop it here and yeah just lower it till it okay yeah so the problem by why that one is starting to look weird is because this says normals and that doesn't so as I had said like sometimes if you have a mismatch between attributes it this will start giving warnings automatically see this a warning sign here there's a warning sign there let's do one thing let's do something simpler just take a facet you know drop a facet in here what a facet allows you to do is it allows you to sort of for our purpose we're now going to do smoothing groups with it so you can just come in here and you can do like cuss polygons to about 30 degrees so if I just press shift W yeah so what this is doing is it actually like detaches polygons so it sees the angle that you have typed in here and it just attaches the polygons that are not connected together so you can do this this yes doesn't generate normals so because it's not generating normals you're not getting a mismatch otherwise otherwise we can do it at the end you know that's fine as well like if you come to the end here and I can just take it normal at this point that way everything will get normals you know and we'll keep it to 30 degrees yeah so if we zoom out yeah I think that's fine come in here and do by face area yeah see there you go that's better you know so that looks a lot better and what was before and then you give poly wires to like you know like this one and that one you can give poly wires okay so this is this is the basic chair okay and I'm hoping I think I went went slight faster than normal because you know how to use the table so I don't think this will be you know too complicated it's just a question of knowing you know how to copy or where to copy these back lines you know and then being being able to move it back so as long as you understand that the rest of it is just minor additions you know like the poly extrude and the poly bevel stuff that's you know that's just sort of like adding additional details even though it is useful as I said like you can make groups out of the poly extrude and feed that into the pani bevel so you don't run into any problems like you don't have to like manual selections and stuff so that makes life you know easier okay now now that you have done this much now let's make it slightly more complicated so what I'm going to do is I just want to bypass these poly bevels because I know they're going to cause problems because I haven't figured that part out because I just added these right now so I'm going to do a circular table or a circular chair and I don't know how we'll be able to adjust the pani Bevin into that so I'm going to make temporarily bypass these we'll worry about that later okay okay so what I want to do is I want instead of a rougher Square I want a circle so what I can do is I'll start with a circle and the idea will be that we take a circle and then we figure out a way to extract a square out of this okay so the Square will then feed into the ad and become points and the circle will just go into like you know this place and that place okay once we can figure out how to get a square out of it the rest of it remains the same so what we do is we take the circle and I'm going to change this to NURBS because it will be easier to extract like multiple resolution circles of different so the point is if we can take a circle and bring it down to four points then that becomes a square so this is a NURBS curve so like if he's if we check it here like if I do polygon and then if I bring this down to four sides see that gives me a square but we want to do it on like we want to have two branches coming out of it like one should remain a circle and then one should become a square so I'm going to keep this to NURBS and what you can do is like will keep this higher like this this count does not matter okay as long as it forms a circle you're happy you take something called a resample so a resample is a nice way to increase or decrease number of points on a NURBS curve so usually it's good to sort of smoothen out things like if you have hair curves you can also use resample on that but what it does is it has two options one is you can it can it can increase points based on the length that you provided so low the lower the length is the more the points will increase and the other option is you can also do like precise number of segments so when it says ten segments you know it's doing like exact ten points so if I bring this down to four they go you have a square now before that let's just put it in the ZX plane you know so it's pointing this way it has one issue which will have to take care of in the beginning is the normals tend to face downwards okay like if you check the normals on the C they're facing downwards for the grid the normals are facing up so you know that's a problem so let's take a look at so firstly we will have to reverse the normals on this so which is what you do is you take a reverse here because if you don't do this when it feeds into the poly extrude it will go in the opposite direction because the normals are pointing in the opposite direction okay so this gives me the first piece of the puzzle the only thing now we need to change is because this is you know it will come in at at 45 degrees yeah because then it extracts from it like it's not going to form like a square it will take like four points like these you know and extract like a diamond so if you rotate the diamond to 45 degrees you'll get that so we'll take our transform and we'll rotate it to 45 degrees in the y axis and then you know that gives me a square we're not going to worry about sizes because hopefully we haven't done anything that will cause problems because of the signs okay so now comes the big part which is I need to we need to figure out a way by which we can switch the inputs you know so we can have a square or we can have a circle okay so the way it works is you get something called as a switch and it has to go into two places right so it has to come into like these two which is just the basic back and the top you know the flat where you're going to sit and then it has to come into the act okay so just take us take something called a switch and if we just plug in plug this into the switch okay and you are going to see like it switches between you know the the basic grid like let's let's bring it in from let's bring in the circle just to show you okay like you'll see that it switches between you know these two things so what we want is we will have we have we want two different switches right like the first one the one is four one is just the four points which will go into the ad and then the other one will be like the smooth circle which will go into you know the the seat and the back okay so this is the four points this will come in here and then we are going to take you know these two things to look at role C control V this resample goes back to will keep it up like maximum segments and just increase it a bit and we'll do control C control V okay press Y and this comes in here so this is the base circle okay this is that and this is you know for the points so this comes in here and we'll do a copy paste so let's take a copy here copy parameter and feed into this one as well so that if I change one of these they both will change and these come into this place now if I have done everything right nothing should go wrong and I'm hoping I've done everything right so if I just come in here to the final output and if we take a look at this and if I take the switch value and change it there ever it's weird it's really big okay maybe we should reduce the the size of the yeah they go so if I switch this say we have a table and we have a circular now let's let's try to bring back the poly paper and see what we get so if I take this to circle the poly Bible is going to be like we have quite a few points so let's do one thing let's take the resample and increase the number of points hopefully the bevel will make it round anyways so let us take the poly bevel yeah I think that holds up you know that's not bad we're getting like yeah it's soon at a fast rate but yeah that's why I said you know like we'd have to we'd have to jump around a little bit more like maybe you'd have to do like a poly bevel at this point which we can do actually you know like that doesn't matter yeah okay hold on a second let's try this rate I'm going to leave the poly middle I'm going to take this out and put it before the switch so this automatically bevels and comes in because the point count does not matter here right and then this resample can be smooth or yeah so hopefully like if we just come to the switch and we switch back see that's rounded and this is fine so the poly bevel should come in you know at base level itself where we where we round it beforehand so the switch node is actually very nice like when you want to if you are going to generate like a really complex procedural object that has multiple inputs and stuff then the switch node is really cool right so night if like when we did this case and you want to have like multiple types of railings like maybe you want you want to give options of having like you know rounded rods or maybe square ones or you know something like that then you can have you can have like switches you can have like first input is rounded rod second input is you know square ones third input could be like a little more fancy so you can generate multiple things and feed them in through a switch node and be able to switch between those so one of the reasons I kind of realized that I should do the the chair is because it I could cover a few more topics so primarily being like a lot of stuff here is the same like there's nothing too new we figured out we're done groups previously we saw another usage of groups also we saw how to generate groups automatically from the poly extrude and then feed them into a poly bevel so we could do this kind of rounding and thus which is the important thing right we figured out how to do switches and also how to do you know how to have multiple channel references like when we needed to move this on top so we did like the table thickness plus the leg height and also we got to do both those things and now as a final thing we will just add the poly wire okay so just like turnoff do vertex textures now here's something interesting like every time I have to turn this off right every time have to come in here and turn off do vertex section if you wanted to be aw off by default once you've turned it off don't make any changes to any of the parameters click on the gear and say save as permanent defaults so once this is done now if I make if I make a poly wire again it'll always go off okay so it just makes life easier so come in here we'll lower this increase the sides let's make 14 sites yeah and we do the same thing there like control C control me after the copy 2 points yeah there you go so there it is this is slightly inside which is fine you know maybe if you won't even move it you know slightly to the front based on the Pawnee by or thickness which would be here yeah it moves up and then maybe you want to move it in the z-axis let's see if we can do this right so I'll do a right click copy parameter let's come to the transform and z-axis pace relative reference yeah there you go see so now as the thickness varies you see that that always sort of sticks on top so that's pretty cool so we can't rotate this as much as we want which is fine and we can have a square or you know a circle and the transform here is what allows me to sort of move it you know front and back see you can have it inside you can move it a little bit more inside like this can be we'll call this as the back position yeah like if you push it too far then it's going to go out so don't push it too far ok but yeah don't push it over 1 like 1 1 is your limit you know you don't want to go over that because once it crosses one it will move out of the boundary of this and yeah I just want to increase the overall size of this yeah let's make it 1.25 in both yeah and maybe take the yeah is not bad-looking we can adjust the the stick height a little bit yeah okay so there you go so much more complicated than what was before so for those of you who managed to figure it out great I still have as I said I'm sorry I still haven't seen the files but I'm hoping you like I covered a few more things so you get like a few more ideas of what you can do with it but yeah I will check out of your files today and you know get back to you okay so once again happy new year and I hope as usual this this particular tutorial was useful and if you have any questions you know regarding this all the usual stuff blah blah blah you can ask me questions wherever send me ow that was a Harry Potter joke okay so yeah anyways the point is I don't even drink and I'm still this crazy but yeah so anyways I hope this lesson was was clear if you have any problems regarding this or anything else in general you can you know write me emails send me a message on YouTube or Vimeo whatever is convenient to you and that's basically it so in the next lesson before that's basically it we will start with a tribute so that is very important attributes is like a huge huge part of TV so we'll start with attributes in the next lesson and that's basically it

Channel: Rohan Dalvi

Views: 6,003

Keywords: Houdini, vfx, procedural, modeling, tutorial, beginner

Id: _AMJtlqnqOY

Length: 36min 51sec (2211 seconds)

Published: Mon Jan 01 2018