How and Why to Use Booleans in ZBrush

hi i'm scott from the rio grande tech team and today i'm going to be talking about boolean operations within zbrush so let's get started okay so i've got zbrush booted up and the first thing we need to do is we need to bring in a couple of subtools so i'm going to navigate to my tool palette here and i'm going to bring in a cube 3d so i'm going to click and drag to bring this out into my scene immediately hit the t key to go into edit mode and i'm going to go ahead and make this a poly mesh 3d by clicking up here in the tool palette so we need to add one more sub tool to our scene here uh and i'm gonna navigate to the subtool palette expand that and i'm gonna go down to append and i'm gonna bring in a sphere 3d and now it's inside of our cube so i'm going to want to select it and i'm going to use the gizmo to kind of move it out of the way so go up here and click on move bring up the gizmo and then we're just going to bring this out somewhere where we can see it but we want to keep these overlapping so what booleans are is a way to either add subtools together subtract them from one another or create new pieces from where they intersect so this will this will become pretty pretty apparent once we start getting into it but in order to start doing our booleans the first thing we need to do is we need to go up here next to the light box and turn on our live boolean system so just click on that and make sure that it's highlighted so i'm going to go back to the first object in our scene which is our cube and all of the boolean operations are going to take place within this subtool palette here so the first thing i need to do is select where the boolean is going to start and if you have a lot of subtools here you can actually control where what objects are involved in that boolean and leave out others so the way you do that is the the the first object you would click here on this first box this it's got a little arrow here and these three options here are our three boolean functions we have boolean addition or boolean add subtract is the second one and intersection is the third one so i'm going to go ahead and click on this arrow and it's going to tell zbrush that this is where we want the boolean to start and then we need to select how we want this sphere to interact with this cube so right now uh it is on boolean add so if we were to go ahead and run this boolean it would add these two objects together as one single mesh because the thing we're trying to eliminate and i'll show you i'll turn on transparent mode so you can see what i'm talking about so right now because we have these two intersecting primitives we have some geometry on the inside that's overlapping so we have this kind of portion right in here where these two are overlapping now this becomes important when we want to go to 3d print if you're if you have this kind of overlapping geometry your your 3d printing software will see this cube and the sphere as solid objects but then you have this overlapping geometry so it can become confused uh it can most of the time it results in print errors because it doesn't know whether this is a solid piece or because it has geometry on the inside if you're going to be taking this out for 3d printing it's best to eliminate this internal geometry and that's where that's what booleans are going to do for us so i'm going to turn off transparent mode again the nice part about zbrush is we can use this live bullion system to see what it's going to look like in real time so right now i have it on a boolean add so if we were to run our boolean this is exactly what the piece is going to look like minus that internal geometry that we looked at just a second ago now if i go over to boolean subtract which is the second option here you can see it's actually cutting away from that from that cube we're actually using that second sub tool as a cutter when we bully and subtract and you can see i've got some faceting on the inside and that's because we didn't add any subdivisions to our sphere so if i were to go back to we'll go back to add just so we can see the sphere and i'm going to open up the geometry palette and i'm just going to give the sphere some gotta select the sphere first there we go and i'm going to give that some subdivisions so i'm going to click that a couple times just get it a bit smoother than what it was before now go back to my sub tool palette and now do the boolean subtraction and you can see that cutaway is much smoother now that we have some subdivisions there so the last one is our intersection so when i click on intersection it's going to take that overlapping geometry and it's going to make a new sub tool just from that area so this affords some really interesting design capabilities when you start overlapping shapes and there's some great tutorials in the z classroom that demonstrate this but this allows you to create new sub tools from that overlapping geometry and the nice part about this live boolean system i'm going to go back to subtract real quick is that i can move it in real time so my sphere is here it's actually cutting away from the from the cube but it's actually still there this is just the live bullion system is showing us preview of what this is going to look like so i can actually go up to move move scale or rotate and get my gizmo here and i can actually move it in real time to make sure that i've dialed it in and got it just where i want it now this is different from a lot of other systems like different cad programs where you you set up the boolean you run it see what it looks like if it's not quite right you have to undo the boolean readjust rerun it this allows us to actually see what it's going to look like in real time before we make that commitment of doing the the boolean boolean operations they can have a lot of calculations associated with them so they can be uh they can take a little while to to run but this is a very simple boolean so it won't take any time at all so once you have everything where you want it in order to execute this boolean on our subtool palette you would go down to the boolean sub menu down here so go ahead and click on that and then click make boolean mesh so when we click that you'll notice it doesn't actually come into our scene here it actually comes in as a new tool in the tool menu so i can either append this back in if i want or i can just click up here and now i have my boolean piece and now i can i can do whatever i want to it i can do more booleans i can do uh you know start sculpting on this add it in as some kind of design element or what have you okay so now uh let's do one more demonstration uh let's let's show a bit more about uh the intersection because there are a lot of interesting possibilities with that uh so i'm going to go back into my tool menu and i'm going to bring a sphere back out or a cube back out i'm going to make out a poly mesh 3d and i'm going to append in my sphere one more time so spheres on the inside i'm going to go ahead and select it and then i'm going to go to my gizmo by clicking the move button and i'm going to use this yellow circle on the inside to scale the whole thing up so it's larger than the cube i'm going to go ahead and set up the boolean again so i have like boolean checked that is highlighted so i'm going to start it at the cube because that's my first subtool and i'm going to click boolean intersection now you'll notice the sphere just kind of disappeared so and that's because we have this set to to boolean intersection but there's no intersecting points right now uh so what we're going to do is we're going to shrink down the sphere until it starts making contact with this cube and i'm going to bring my gizmo back up by clicking the move tool and take this yellow box and i'm just going to click and drag and start bringing this down now again i don't have any subdivisions on my sphere but i can if you ever need to you can always just turn off live bullion for for a second if you need to see both of them and i'm going to go back into the geometry palette and i'm going to add some subdivisions just to smooth everything out makes for a much cleaner boolean and then i can turn live boolean back on see that's much better and you can see just by bringing down a sphere over a cube we're already getting some some kind of interesting design elements there and then i can incorporate more subtools later you know to really make this unique uh but yeah there's there's a lot of possibilities just within this boolean intersection uh for creating some really interesting stuff so so right now uh i'm gonna go ahead and run that i think that looks pretty good i can actually turn off my gizmo if i want so yeah that looks pretty good i'm going to go ahead and to execute this boolean back in the subtool menu here under the boolean submenu i'm going to click make boolean mesh and you can see a little progress bar at the top if you have a boolean that's really complex complicated you'll see that status bar at the top letting you know uh how close it is to being done and then i can go ahead and bring in my new subtool so one of the nice parts about using this boolean system is that uh you saw that i was actually adding subdivisions to my sphere to make for a cleaner surface so i'm getting a much cleaner surface here uh there is another way of doing that that's not going to uh mess with your active points or your total point system and that's by using dynamic subdivisions so i'll show you what i mean by that uh so we're just going to keep working with this piece so i'm going to append in a cylinder and i'm going to select the cylinder and i'm going to use my gizmo to kind of stretch it out just a little bit and then go into the top view and kind of bring this down i'm going to leave just a little bit of a flat spot right there so right now i don't have any subdivisions that i've added to this cylinder so you're getting this kind of faceting effect but i've got my got my cylinder selected so i'm going to go into the geometry palette and i'm going to find dynamic subdivisions and i'm just going to turn it on i'm not going to click apply because that will then add these subdivisions to the cylinder and increase my active point count right now this is just a uh kind of a mock up of what this piece will this cylinder will look like after i've applied these subdivisions uh but i can actually do booleans with these using the system so that way i don't have to add all those subdivisions and make the boolean that much more complicated and take that much longer so i'm going to go ahead and add the same thing to here and over here so i'm going to navigate back to the subtool palette here and i've got my cylinder selected i'm just going to click duplicate to add another one in there and then i'm going to use the gizmo by clicking on the move button and i'm going to grab this rotate line here and i'm going to hold shift while i bring it down 90 degrees okay so we need to do one more so i've still got this one highlighted so i'm going to go ahead and click duplicate on that and now i'm going to do the same thing i did before holding shift until it locks into place so now i've got i've got this going on so now we need to go ahead and boolean these out so i'm going to do the exact same process before i've got live boolean turned on my mesh that i'm working with i'm going to hit the start button and then i'm going to turn all of these to boolean subtraction so now we're getting something like this so this could be something like a bead or some other kind of design element or you know whatever you happen to be making um you know you can you can use this in your in your jewelry i've got everything set up uh got start button got it all set to bully and subtract and now there is one more thing that i have to do before i execute this so because i'm using dynamic subdivisions on these three cylinders here under the boolean sub menu there's a button right next to the button we've been clicking called allow cyan dynamic subdiv or dsdiv i just need to click that and make sure that that's highlighted and that's telling zbrush that we will be bullying booleaning with models that have dynamic subdivisions applied and when i click make boolean mesh it will populate in my tool palette up here and and now i've got this design element that i can use one thing to be aware of when you're doing booleans uh let's say let's say i'm using this technique to get a basic shape going and then i'm going to start sculpting on it so one thing that you'll want to you want to look out for is i'm going to turn on poly frames we're going to take a look at the geometry of this i'm going to zoom in here so you can see on the outside here i've got some nice even geometry this is great for getting started sculpting but i've got a lot of variation in here i've got some weird triangles going on around these edges i've got more kind of strange triangles around these corners if you're not going to be doing any sculpting on this then this is not a bad thing you can you can add this in as a design element but if you're going to be doing any kind of sculpting around it like say let me turn off the poly frames real quick if i want to smooth out these corners a bit you can see if i hold shift to bring up my smooth brush you can see how it's not exactly smooth it gets a bit jagged in areas even right around here you get some strange geometry so we would need to do one thing first so i'm going to control z to undo that and and again if this is uh if this is just something that you're bringing into your scene and there won't be any sculpting on it this is fine you can keep going uh but if you are gonna do any sculpting then this next step uh would would be beneficial so we need to change the geometry of this and the first thing we're going to try and just take a look and see how it works is we're going to try to z remesh so we're going to navigate to our geometry palette here and there is a option for z remesher and i'm going to go ahead and click the button to start that and we'll see how this comes out so it came out a bit rough i'm not really happy with that you can see how we've got some little jagged bits here um yeah i got some broken geometry here it's not really that doesn't really look good i'm not really happy with that so so let's go ahead and control z and undo that and we'll try we'll try one more method let's try a dynamesh so uh still in the geometry palette i'm going to click on dynamesh and i'm going to turn the resolution up just a little bit to about 304 and now i'm going to hit dynamesh now that looks much better so if i turn on my poly frames again you can see i've got much better geometry in all of these different areas we've eliminated a lot of those triangles and and we have just a lot more to work with and uh and we've also got some some different poly groups that we can we can use to our advantage later so i'm going to turn off poly frames and now when i go in to smooth out these corners should be a little a little cleaner yeah that's much better so i can go in kind of clean these up a little bit if i need to and and go on from there so those are just a few quick ways to um kind of clean these edges up you can see i got a bit of fastening from the dynamic subdivisions uh again i can go in with a smooth brush and i'm just holding shift normally i would have symmetry on but now you can kind of clean these up if you want or you can just forego the dynamic subdivision booleans and and just add some subdivisions to it later or before you actually do the boolean okay so the next thing i want to show you is there's a way to do some simple booleans actually using dynamesh so i'm going to bring my cube back out i'm just clicking uh the the cube is already in here so i'm going to go ahead and just click that bring that back into our scene i'm going to make it a polymesh3d and i'm going to go ahead and turn on dynamesh so now we've made our cube a dynamesh object and we need to bring our sphere back in so i'm going to click on our subtool palette and click append and select the sphere and then i'm going to select it in the sub tool menu click on move to bring out our gizmo and now i'm gonna just kind of bring it out here just so we can see it it's not really a boolean it's it's still dynamesh but it's uh it is very similar for this operation we can actually turn off live bullion because for this we're not going to need it and i'm going to get my gizmo out of the way as well i'm going to select my cube here when you're using dynamesh to do either you can use dynamesh to do either a boolean addition or subtraction uh you can't you can't use intersection in this instance but we just need to make sure that the first object that we're going to be doing this with is a dynamesh object the sphere it doesn't matter if that's dynamesh or not this will work the same way so we've got this as a dynamesh object we've got our sphere in here first thing we need to do is we need to select what effect we want this sphere to have on our cube and i'm going to leave it as the boolean add or boolean edition we're going to add these two together and get rid of that internal geometry that we saw at the very beginning so the first thing i have to do when i'm doing these kinds of commands with dynamesh is i need to merge them together right now they're two separate sub tools i need them to be one sub tool so the way i do that is i've got the top one selected and in my subtool palette i'm going to go down to merge and we've got a few options in here the one we're interested in is merge down so that's actually going to look at the sub tool that's just below the one we have highlighted and it will merge that together you also have ones like merge visible which will merge all of the sub tools that are visible and merge similar which will actually look at similar sub tools in your list and merge those together but for right now i'm just going to go ahead and click merge down and it's always going to give you this little window at the beginning so you can either click ok or click always okay either way always okay we'll make sure that box doesn't come up again so i'm going to click that and now we've merged these two together and now i'm just going to re-dynamesh i'm off of my model here i'm going to hold ctrl and drag and there we go now we've dynamesh these two together and you can see i've got a bit of a little fillet here i have the resolution on my dynamesh pretty low so it looks a bit jagged but but that's one way you can merge two items together and i'm not creating a separate subtool that that i have to keep bringing back in or changing to i can just do this right in the scene that i'm in and and if you want to you know give your cad design a bit more of a handcrafted look it does look very similar to a solder seam at low resolutions and i can always go in and kind of clean this up a bit with my smooth brush so you can create some interesting effects there i'm going to go ahead and undo my smooth if we want to do boolean subtraction with this i'm actually going to i'm not going to bring in a new cube or sphere i'm just going to go back now if i hit ctrl z it just gets rid of my sphere because um when you try to un after you've merged something together and try to undo it it will typically just get rid of that other sub tool but we can still split these apart so in your subtotal menu here you have a split area and i'm going to select split to parts and again it'll pop up with that same windows before i'm just clicking always okay and now it's split our two subtools back up so we can work them independently if we need to so for this i'm going to click on the subtraction option and you know because this isn't a a live boolean operation we're not going to get a preview in this instance so you just want to be you can you can check it in by using the live boolean system before you go through with the dynamesh that is an option but just doing it this way you don't actually have a view of what it's going to look like after it's done so same process as before we've got subtract selected we need to merge these together so i'm going to go down to merge and i've got my cube selected so i'm going to merge down and now that those are merged i can re-dynamesh so hold ctrl click and drag and release and now we have same kind of operation again my dynamesh is pretty low resolution so that's why we're getting a bit of a jagged edge here but you can increase the resolution on your dynamesh when you when you put this cube together to make sure that's going to be a little cleaner now just as a reminder this will only work on addition or subtraction you won't be able to do this with intersection you would have to use the live boolean system for that okay so the last thing i want to show you is just a few troubleshooting tips so um so now that we've gone through how to use dynamesh i'm going to actually go back to my cube 3d just by clicking on the cube here in my subtool or in my tool palette or you can click on this little box up here to actually bring in a separate one and now i'm going to go and append in my sphere so i'm going to select the sphere same as before i'm just going of bringing it into our scene and moving it kind of out to the side just so we can we can see it so let's get the gizmo out of the way and while i'm up here i'm going to turn on the live boolean system so we're going to do same as before on our first sub tool we're going to click the uh little arrow there because that's where we want to start the boolean and for our sphere we want to do a boolean difference so i click the subtract and everything disappears same with intersection if i try to do a boolean intersection my sphere and my cube have disappeared and if i go back to addition they're still there so so what's happening here well we missed a very important step when we brought in our cube we forgot to make this a polymesh3d so if you find yourself when you bring in a a primitive from your tool palette and you're trying to do booleans on it and everything is just kind of disappearing uh when you try to do a subtraction or an intersection make sure that you have clicked this box so on my cube if i click make poly mesh 3d we will append our sphere back in select it back to our move tool bring this out so i can see it and then start the boolean here with my cube and then do boolean subtraction or subtract now everything is working the way it's supposed to so just make sure that if you're if you're bringing in a primitive make sure to click that polymesh3d that will make sure that there's no weirdness with your booleans uh if you know if you're if you're going through it in a bit of a rush and you can usually tell if if you have clicked the make polymesh3d because on your subtool here you have a pm uh so that'll kind of let you know that you've you've selected it because the the cube that we selected was this one right here and it doesn't have the pm in front of it for polymesh the other thing to make sure is that on your subtool menu here where you have all your subtools the objects that you're going to be working with in your boolean the one you start with along with everything else make sure that this little eye icon is highlighted because this can cause problems when you're when you're doing your booleans you can see as i as i turn this off and on if you try to do a boolean with a sphere and this little eye icon is not highlighted you won't actually see anything happening so the sphere is still there but it's not actually affecting my cube in any way because i have it hidden so just make sure that when you when you're doing these booleans make sure these little eye icons are highlighted uh and and that way you're not going to have any unforeseen issues with your booleans uh so that's pretty much it for booleans uh feel free to play with with these uh there's a lot of design capabilities uh it's a very effective way of doing hard edge modeling within zbrush so if you have any questions uh feel free to contact us and have a nice day

Channel: Rio Grande

Views: 26,631

Keywords: zbrush, boolean, booleans, fttt, scott bradford, tutorial, 3D design, 3D manufacturing, 3D Jewelry design, digital sculpting

Id: 8nbuJKkbVog

Length: 30min 18sec (1818 seconds)

Published: Tue Nov 24 2020