Do THIS before you boolean! (Curvature Trick)

hey guys i got a quick little video for you here today this is going to be a very very useful trick so you're going to see i have two cylinders here and they are fused together using a subd modifier and if we go into wireframe you're going to see pretty clean topology right so i'm going to show you a really easy way to join these two together to fuse these two together with sub d that takes you no time at all so basically the way i did this was i added in a cylinder right i set it to 16 vertices 16 is a good amount and i just rotated this 90 degrees over the y scaled this a bit on the x and then what i did was i duplicated it and then rotated it like this and then just kind of positioned it in here kind of like that right now what i usually would have done was i would have just kind of arbitrarily positioned this here and then union these two together so we just come in and run a union boolean and then apply it and obviously in order to run a sub d on this we'd have to re-topologize it into quads so if i were to do that here essentially what i'd be doing is i'd be merging these near miss vertices together so i'd merge these two i'd merge these two i'd merge these two but there's one problem with this technique here and you're going to notice that whenever i merge some of these together what ends up happening is the curvature of these cylinders get disturbed pretty heavily and what i mean by that is if i were to for example slide this vertex down you're gonna see the curvature now gets disturbed it's not evenly distributed around the circle and that's the same thing that happens here when i merge these together the cylinders curvature gets disturbed and disturbing the curvature is okay but you don't want to do it to the point where it's noticeable and merging these two is pretty noticeable even if you merge them at the center and meet in the middle this um this is pretty disturbed you're going to see it's it's very obvious where it's kind of uneven right and if i were to do it here you're going to see this one isn't too bad it doesn't get disturbed too much but you know some of these like a decision we have to make here could actually disturb either of these pretty heavily i either disturb this one or i end up disturbing this one and there's just no even you know like middle ground for this to work so i'd end up having to add in extra geo and joining it here in order to not disturb that area right so that's like my only solution then eventually i'd probably be left with either this weird quad right here or i'd be left with a triangle if i chose to just run the triangle right here which would probably cause some pinching or i could of course try to merge that down but then you know same effect happens so you should actually do before you union anything together is you should do this let me show you so we're going to do is just start this over again we're going to add a cylinder with 16 vertices rotate this 90 degrees scale it up a bit and then same idea shift d we'll rotate this one and then do something like this now before we just you know apply our boolean and move on with life we want to make some considerations here in order to avoid the issues that i just showed you what we can do is you know strategically place this in a location that will mitigate that curvature being disturbed so what i like to do here is you can imagine when these two get fused together this will turn into a vertex and this will turn into a vertex and that's kind of obvious because if i apply the boolean right you're going to see we now have a vertex here and a vertex here so at the points where they you know merge together that's where the vertices get created so with that in mind what we can do is kind of imagine how much the curvature will get disturbed when we merge these together and you're going to see right here they're so close together that if this got pushed up a little and this got pushed down a little you wouldn't really see much of a difference same for this area right here this one would be a pretty heavy effect on it because this would either have to move up here or this move down here and that would be a pretty heavy movement because this is directly in the center of this face so what my goal is is to align all of these areas up so that way i know ahead of time that i'm barely going to have to move these vertices at all so what i try to do is align these points almost overlapping each other or just a bit off of each other and i'd really try to get all these points as close together as possible so that way i'm really mitigating the amount i actually have to move those vertices around so i'm probably going to do something like this we're just going to kind of meet in the middle there so this doesn't have to move very much this doesn't have to move very much and same for these two now we just need to check the back this one's going to have to move pretty heavily unfortunately so we're going to have to make some more changes just move that up a bit and you're going to see just have to kind of play with it and see what we can get and this is actually a very clean solution all of these points are very close together which means when they get merged together the curvature is barely going to be disturbed so check this out now what i can do is merge these two together with a union boolean we'll apply the boolean and if i go in here and start merging these together at the center you're going to see the curvature barely moves it's not really that noticeable same for right here if i repeat that and i repeat this these points are so close to each other that the curvature is barely moving which is a good thing because we're not going to see any difference really so all we have to do is merge all these together so that way we have a set of quads all the way around here right and now we have the freedom to just come in here and basically we topologize this into quads we can join that here we can join this here join this here you get the point so now whenever i add in these vertices or these edges rather and join up the vertices we have nice quad-based topology which allows us to run a sub d so i'll just run one more loop right here and join that up and maybe we'll just slide this back a little bit so that way it's kind of following as it should the bottom here we have to do the same thing we're going to have to add in a loop join that together join this together and then join one more together right here and i'll just hit it with a symmetry to save some time like that and then what i can do is simply run a bevel around these areas we'll do ctrl b two segments and set the profile to one do the same thing here ctrl b this will add basically a natural proximity loop around the entire thing we're going to need to dissolve that out ctrl b and then ctrl b again and same thing for this little connection point we'll just run a proximity loop around here and now i can just press ctrl b and run a sub surf and you're going to see we have a very very clean result here and obviously if i want to make this a bit bigger i could kind of slide this up a little bit and kind of move these loops around as i as i wish right but the important part here is we have a nice fusion here and the entire topology is based out of quads without disturbing the curvature of the original cylinders you're going to see the areas we merged together are so barely moved that you can't see any curvature disturbance otherwise it would look something like this where we wouldn't have been able to you know flow it through as nicely we would have had to move the vertices really high up and it would have caused this nasty flat area which is you know not good and doesn't look like a cylinder anymore so that's how i actually approach these fusions beforehand i can kind of picture where those vertices will be positioned and how much i have to merge those vertices together to determine if it hurts the curvature or not so i hope the video helped hopefully this gave you an idea of how you can think about topology before you actually use any booleans it can be very beneficial and save you a lot of time so thanks much for watching guys and i'll see you in the next video

Channel: Josh Gambrell

Views: 37,553

Rating: 4.5228629 out of 5

Keywords: blender tutorial, blender hard surface modeling, hard surface modeling blender, blender box cutter, blender hardops, blender boolean, blender, blender hard surface, josh gambrell, hard surface blender, do this before you boolean, curvature trick, blender curvature, blender hard surface modeling tutorial, boolean blender, hard ops blender, hard ops tutorial, boxcutter tutorial, blender bros, ponte ryuurui, masterxeon1001, blender subd, blender topology, ngons, quads

Id: cng9UdeY69k

Length: 8min 7sec (487 seconds)

Published: Sun Aug 29 2021