revolver cylinder in zbrush

Biomechd

hey, i've been a lurker here at the polycount forums for a while, looking at other peoples' artwork and such. i decided to finally register because i'm having a method problem and can't find any answers when i google all over the internet. i'm a blender user who has started using zbrush to easily add details to my models that would take forever otherwise.

just a couple days ago, i started a project working on the "performance center" version of the smith and wesson 500 revolver. i've got the shapes all made out and i've exported the cylinder from blender to zbrush. i've looked all over for ways to create the chambers and the one thing i found that would do it creates oval-shaped chambers instead of circular chambers.

what i do that creates the oval-shaped chambers is i create a circular mask over the end of the cylinder, with radial symmetry applied. then i invert the mask and extract the newly-masked portion of the object as a new tool. i don't know if there's some extra step i can add to this process to make sure the chambers stay round, or if i have to go through an entirely different process to achieve the result i want.

for anyone who's wondering, i do plan on importing other parts into zbrush so that i can add extra detail, but i'd like to have the cylinder done first. i've never been able to figure out how to add the details to a revolver's cylinder, so i'd like to know how to do it.

GeeDave

Would it not be easier to perhaps complete the base mesh in blender first? I mean "six holes in a barrel" would be something I'd personally throw into the base mesh. I don't mean to cause offence... but it seems you're trying to jump the gun a bit.

(LOL PUN)

EarthQuake

I'm pretty confused as to why you would be doing any of this in zbrush, let alone the holes in the cylinder. A hard surface gun is most likely suited much better to traditional Sub-d modeling.

Biomechd

well, i could never figure out how to create the chambers in the cylinder using regular poly/sub-d modeling. so i figured that if i imported it into zbrush, that i'd be able to do it with little difficulty, and then i could just import it back into blender.

EarthQuake

Maybe this will help:

cryrid

It wont be the popular route here, but if you just like to create stuff and want to try doing everything in zbrush for the fun of it, Shadowbox + circle clipping /masking can go surprisingly far towards creating revolver chambers (holes, grooves and all) in just a short amount of time. But it can require more finesse with the tools in order to get the control over the sharpness and bevels down to your desire, so unless you've messed around with hard surface sculpting a lot you'll probably find the traditional modeling methods to offer you better results in the same amount of time.

Biomechd

thanks EQ, i'll try creating the chambers in the cylinder that way when i get back to the project.

and as for hard-surface sculpting, no i haven't really done anything with it. i experimented with mudbox a bit, but found out that i couldn't create holes and couldn't lump objects together. then my brother showed me zbrush, which i'd heard about but hadn't really paid much mind to it.

Snowfly

Extruding and beveling a curve in Blender can get you most of the way there, since shapes inside shapes render as holes-


Blender scene

It would require a ton of cleanup though, so EQ's way is still the best way to go.

Biomechd

the cylinder's chambers are pretty much done. the edges aren't completely circular, but it looks like the chambers themselves are. since the smith and wesson 500 is a 5-shot revolver (as snowfly shows in his screenshot), i have a pentagon in the center instead of a hexagon. because of this, i have to have tri caps instead of quad caps, and i believe this to also be the cause of the edge-smoothing issue.

would anyone like me to upload the file or show my wires so that they can see what's going on?

in my opinion, though, the tri caps don't really matter for pentagons. they don't get deformed when subdivided, unlike 32-sided cylinders.

Snowfly

Yeah, capping the ends with triangles shouldn't cause any problems like you said, but you do have to add quite few support edges to maintain the circle-ness of the chamber openings. Go ahead and post an image, I think you'll get more solid feedback that way.

Here's what I came up with in Blender. Triangles all over the place-

Biomechd

here's a current render of the cylinder. the two on either side are emitting just a bit of light to make the wires a bit easier to see. the other side looks exactly the same, since i just duplicated the faces and merged the vertices, with the only difference being a larger pivot.

Biomechd

seems it didn't work, for me at least.

Snowfly

dude the main cylinder should have a number of sides divisible by 5, to better match up with the 5 chambers. You're just making it harder to add the recesses on the sides later by using the default 32.

Biomechd

how's this? i think that my only problem now is sharpening the edges around the recesses between the chambers. i also have to make the cuts near the back of the cylinder.

Snowfly

looking good! well, you basically want to restate the parts i marked in green with support edges. How you do that is something you'll have to figure out yourself though, since there are no ready loops that you can just cut into so you have to reroute. It wasn't very hard to do though, I just used a edge slide to push the new edge loops right up to the corners, and then slid them back again a bit.

Biomechd

it looks like i could undo the recesses, then extrude them as opposed to scaling them in. then just fix the geometry to create the nice curves that i want.

Biomechd

and here is the result of the extruding method. i noticed after i uploaded the render that i need to curve the recessions a bit more.

jordan.kocon

Not sure if you are still working on this, or if it will help, but here is a chamber a I recently made...

Biomechd

that's pretty good, though the recesses seem a little too big, but i'm also having that problem. i also think the chambers in the cylinder might be just a little small (unless it's a .22 caliber or something) and too close to the pivot point. chambers are usually centered between the pivot and the outside of the cylinder.

mind posting some side shots? some details are a little difficult to see that well.

also, for future reference, you'll get cleaner meshes if you create a cylinder and model the details into it rather than creating part of the shape and extruding it. not only will you have cleaner meshes, but it will also save you some time and trouble. if you look at the wireframe on my cylinder, you can see that i created a cylinder, scaled it to the diameter and length that i needed, then i began creating details. i also took EQ's advice for connecting the outer cylinder to the chambers.

and, this is just me, but i'd make the entire thing one object, if possible, unless you're going to make the ejector pin move separately as part of an animation.

jordan.kocon

Biomechd: Yea I am by no means an expert modeler, and certainly no gun enthusiast. With that said, I wanted this to be a quick practice in sub-d modeling. While the gun is not 100% accurate, possibly far from it, I wanted to practice my modeling and not exact recreation. However I due know that modeling is all about recreating from concept, etc. With that said I know my method is not the best or perfect, but I am happy with the result Screens, including my new renders:

Biomechd

that's pretty cool, though the grip looks a little too wide. what gun is it based on? or did you just make a random revolver and add fallout-like modifications to it?

what program was it made in?

EDIT: i just noticed that the indents in the rear of the cylinder aren't aligned with the recesses that go along the length. in my revolver reference, the rectangular indents are centered with the recesses. still looks good, though.

jordan.kocon

ya I dont know why, but I had a hell of a time with the grip... really not pleased with that part. It's based off a colt python .357, and I just added stuff onto it. In my reference, the indents are in between each recess, so I think mine is accurate. It was modeled and rendered in Softimage.

Biomechd

could you post wires for the grip? i just wanna see how the vertices are laid out, so i can see whether you can scale part of it, or whether it'd be easier (and neater) to just scale the entire object.

jordan.kocon

Hey sorry, been busy lately. Here are wires of the grip, I know it is fat, but I just wanted to get it done. I think I could maybe fix it with a lattice.

cryrid

Well since this thread is still popping up, I saw this today and figured it might as well belong here:
http://www.zbrushcentral.com/showpost.php?p=863003&postcount=23