Sculpt SCI-FI CON­CEPTS IN vr

Free­lance il­lus­tra­tor Martin Ne­be­long demon­strates how to quickly model sci-fi con­cepts in VR

3D World - - CONTENTS -

We dive into Master­piecevr in this tu­to­rial by Martin Ne­be­long, as we learn how to quickly sculpt some amaz­ing sci-fi space­ships us­ing the power and free­dom of VR sculpting soft­ware

Ihave had my VR head­set since mid 2017 now, and since I got it it has changed the way I work. I’ve dab­bled a bit in 3D, but have al­ways seen my­self as a 2D artist. I never re­ally felt ‘free’ when work­ing in 3D with Max or Zbrush, and never got the feel­ing of cre­ative free­dom that I have when work­ing with a sketch in Pen­cil or in Pho­to­shop. Vir­tual re­al­ity has changed that. My ini­tial ex­pe­ri­ences were mainly with Ocu­lus Medium and Quill, but since then I’ve also been us­ing a bit of Grav­ity Sketch and quite a lot of Master­piecevr (which I’ll be us­ing in this tu­to­rial). I’ve been us­ing Master­piecevr since its beta days, and it’s evolved a lot since then and has re­ally started to come into its own. Re­cently the team be­hind Master­piecevr in­tro­duced grid snap­ping and line con­straints, which is a tremen­dous help when you’re work­ing with hard-sur­face mod­el­ling.

Master­piecevr con­tains both voxel and poly­gon tools which is great, since each tech­nol­ogy is good for dif­fer­ent things. For ex­am­ple, I of­ten use poly­gon tools for fo­liage, grass and de­tails on char­ac­ters.

In this tu­to­rial I’ll be fo­cus­ing on sculpting quick space­ship con­cepts di­rectly in VR with­out any prior sketch­ing or plan­ning. Each sculpt took be­tween 30 min­utes and an hour to sculpt in VR. In all of them I use Master­piecevr’s snap­ping tools, and the copy/paste func­tion­al­ity of the pro­gram.

The last part of the tu­to­rial will be about the process of get­ting the sculpt from VR into a tra­di­tional work­flow of UVS, tex­tures and ren­der­ing. Since the process in­volves a lot of steps, some of them will only be briefly de­scribed. You can watch the videos to go into more de­tail.

change the shape of the stamp By push­ing the Beta but­ton un­der­neath your main sculpting hand with the laser point of your left hand, you get ac­cess to chang­ing the shape of the stamp you’re us­ing. This is a very pow­er­ful fea­ture, and one I use quite of­ten. For ex­am­ple, you could change the square stamp to be a big, flat plane that can quickly be used to mock up a build­ing. This also works for the se­lect/copy/ paste func­tion in Master­piecevr.

01 Ini­tial setup

Fire up Master­piecevr, and you’ll be greeted by the stan­dard screen. Here you have a stu­dio-like environment, and on the left hand you have a tool pal­ette. The right hand is your sculpting hand (this can be changed in the pref­er­ences).

If you have a fast com­puter with a good graph­ics card, you can up the res­o­lu­tion of the scene to 6x or even 8x. You can al­ways down­res again, but re­mem­ber that the de­tail you lose by do­ing this is lost for­ever. For hard-sur­face mod­el­ling it makes sense to up the res­o­lu­tion.

02 the tool­bar

The main tool­bar con­sists of the voxel sculpting tools. You have eight dif­fer­ent stamp shapes, you can se­lect a colour and you can con­trol strength and size. You can choose to ei­ther add or sub­tract with the ba­sic tool. There’s also Shrink, Smooth, Noise, Pinch, Bulge, Smudge and Twist. I use Smooth and Noise the most here.

03 Get to know the Main sculpting tools

Play around with the ba­sic tools un­til you feel com­fort­able with them. For the main part of this tu­to­rial I sculpt in grey clay only, as I’ll be tex­tur­ing the ships out­side of VR. You do have the op­tion of ex­port­ing with ver­tex colour if that suits the par­tic­u­lar work­flow you’re us­ing.

In this ex­am­ple I’ve switched be­tween the dif­fer­ent tools to give you an idea of the op­tions you have. Per­son­ally I use the Sculpt/draw tool the most, with a square stamp shape. I switch be­tween Draw and Erase as I go along.

You also have the Brush tools, which are poly­gon based. These are more like the tools you might know from Tilt Brush or Quill.

04 GUIDE tools

Guide tools are a new ad­di­tion to Master­piecevr, and they make a world of dif­fer­ence if you’re sculpting hard-sur­face ob­jects. There are a va­ri­ety of tools here, and the ones I use the most are An­gle Con­straint, Grid, Mir­ror and Line Con­straint.

05 se­lect tools

The Se­lect tool in Master­piecevr lets you se­lect part of your mesh, and then cut/copy and paste it. This is great for a lot of sce­nar­ios, and it copies both form and colour, and works with both Voxel (Sculpt) tools, and Brush (Poly­gon) tools. In this ex­am­ple I sculpted a ba­sic rock, and then copied and pasted that a few times. I drew a few blades of grass, and copied and pasted that.

06 sketch In Vr

Let’s get started on the main part of the tu­to­rial. In this phase, I’ll be us­ing the main sculpting tool, to quickly block in a form for my ship.

Re­mem­ber to up the res­o­lu­tion here. Go all the way up to 8x if your com­puter can han­dle it and make sure to use as big a part of the sculpt ar­eas as you can.

When you block in the shape, switch be­tween add and sub­tract and carve out a form. You could also

opt to use the poly­gon brush tools as a way of sketch­ing in the form. I have Mir­ror turned on here.

07 re­fine the form

Once you set­tle on a sketch you like, it’s time to re­fine the form. I start us­ing the guide tools now, mainly the Line and An­gle tools. By switch­ing be­tween dif­fer­ent de­grees of an­gle snap­ping, you can use the Line tool to make bev­elled and an­gled edges. If you need to make con­strained lines or sur­faces out­side of the range of the an­gle snap­ping tool, draw ‘free’ line or sur­face guides and go by those.

08 ADD De­tails

Use the Se­lect tools to add ex­tra de­tails and to quickly mock up shapes. This is sim­i­lar to kit­bash­ing, es­pe­cially if you save your stamps and build up a li­brary of shapes.

If you want to make sure the copies stay in the right place ac­cord­ing to the grid, you have to use grid snap­ping when se­lect­ing the form to be copied. Make sure the Se­lect tool is snap­ping to a grid point when you make the se­lec­tion. Then when you paste this, it should be in the right rel­a­tive po­si­tion to the grid. Use the ba­sic sculpting tools to add or re­move parts of the pasted ge­om­e­try, to avoid too many re­peated shapes.

09 the poly­gon tools

If you need to add ex­tra small de­tails to your sculpt, you can use the poly­gon tools to avoid ‘fuzzy’ ge­om­e­try. I used the poly­gon tools for small de­tails on the sur­face of the ship. Re­mem­ber you can also se­lect/copy/paste poly­gon data.

10 lights

I use the square poly­gon brush to add small win­dows to the ship. I make a row, se­lect/copy/ paste it and re­peat un­til I have the amount of win­dows I’m look­ing for. I use the guide tools to make sure the win­dows align cor­rectly.

11 ADD fi­nal el­e­ments

I load a stamp I made ear­lier of an en­gine ex­haust, and use this com­bined with snap­ping to add the fi­nal el­e­ments to the ship. Re­mem­ber that stamps in Master­piecevr re­tain colour, so if the stamp colour doesn’t fit the sculpt you’re work­ing on, you can just re­colour us­ing the colour tool.

12 fi­nal sculpt

The VR piece of the process is fin­ished now, and the model is ready for UVS, tex­tures and ren­der­ing. Every­thing still looks a bit rough, due to the limited res­o­lu­tion of VR mod­el­ling. I’m sure it’s only a mat­ter of time be­fore we’ll see an in­crease in res­o­lu­tion, en­abling us to com­pletely aban­don tra­di­tional 3D tools.

13 ex­port

Once you’re happy with the sculpt, go ahead and save the file and then go to Ex­port. Here you have the op­tion of sav­ing as an OBJ, FBX or STL file. You also get to choose if you want to ex­port voxel data, poly­gon data or both.

I go with OBJ here, and split the space­ship in Zbrush. If you’re us­ing the na­tive Ocu­lus ver­sion of Master­piecevr, you can also choose to dec­i­mate the mesh di­rectly on ex­port. Now exit Master­piecevr and re­turn to the real world!

14 Zbrush Im­port

This step is to pre­pare the model for UVS. I’ll make sure the model is ro­tated cor­rectly, make a low poly and later bake de­tails us­ing the high-poly ver­sion, and I’ll clean up the mesh if needed and sep­a­rate voxel data and poly­gon data. This step can be done in any 3D pack­age that im­ports OBJ or FBX, and en­ables you to dec­i­mate or re­topol­o­gise a mesh.

For the rest of the tu­to­rial, I’ll be us­ing an­other one of the nine ships. First I make sure to ro­tate the model so it fits the Zbrush ground plane. If you ex­ported as FBX, your model will con­tain sev­eral subtools if you used poly­gon data. If so, use Zbrush’s ro­tate all lay­ers func­tion.

15 sep­a­rate el­e­ments

Use the Auto Groups func­tion in the Poly­groups menu. This will sep­a­rate the el­e­ments from Master­piecevr. This means that vox­els will be a group and poly­gon el­e­ments will be in­di­vid­ual

save stamps Once you’ve used the Se­lect tool to copy some­thing, you get the op­tion of sav­ing this as a stamp. That way you can sculpt a jet en­gine for ex­am­ple, save that, and al­ways have easy ac­cess to it should you need it for an­other model later on.

el­e­ments. Each poly­gon el­e­ment is as­signed a unique poly­group. For this project, I want all poly­gon el­e­ments to be one group, so I hold down Ctrl+shift and left-click on the big voxel group to show only that group. Then I Ctrl+shift-drag out­side the ob­ject to in­vert what’s shown. Now I only see the poly­gon el­e­ments, and I can press Ctrl+w to give them the same poly­group. Lastly, go to the Subtool menu, se­lect Split and Groups Split. Now the voxel and poly­gon el­e­ment is sep­a­rated into two subtools.

16 Dec­i­mate and ex­port

Since the ob­ject ex­ported from VR is pretty heavy in poly­gon count, I dec­i­mate the mesh in Zbrush. For the voxel part I go from around 500.000 ac­tive points, to 42.000 which will get me bet­ter per­for­mance in the UV step. Be­fore I dec­i­mate though, I ex­port the hull of the space­ship as one high-res OBJ, and the win­dows or poly­gon data as an­other. I do this be­cause only the hull will need UVS, since the win­dows will have an emis­sive ma­te­rial in the ren­der­ing phase, with­out the need for a tex­ture map.

I don’t mind that I’ll lose some de­tails in the dec­i­ma­tion, as I’ll be bak­ing nor­mal maps us­ing the high­res mesh. As long as the over­all shape is re­tained, my nor­mal map should en­sure I get enough de­tail.

I use Dec­i­ma­tion Mas­ter un­der Plug­ins and se­lect Pre­pro­cess Cur­rent, and then around 42K polys. Fi­nally I hit Dec­i­mate and let Zbrush do its thing. Ex­port the dec­i­mated hull as a low-res OBJ and be sure to name it ac­cord­ingly. Close Zbrush. 17 un­fold3d

The next step is to make the UVS for the low-res hull. Un­fold3d makes UV edit­ing less cum­ber­some, and for projects such as this where pre­ci­sion is not hugely im­por­tant, you can do the UVS au­to­mat­i­cally for the most part. You can also do UVS in Zbrush, 3D-coat, Max or what­ever pro­gram you’re used to.

Once in Un­fold3d, im­port the low-res mesh. Go to the tool­bar to the right Se­lect line mode, and then Mo­saic and auto se­lect. This will give a sug­ges­tion for seam lines. Then hit C on the key­board or se­lect the Cut func­tion in the tool­bar at the top of the screen. This will make UV cuts along all the seam lines. You can also go in and make your own seam lines if you’re not happy with the re­sult, or you can try to auto gen­er­ate us­ing some of the other func­tions of the pro­gram.

18 un­fold and or­gan­ise uv Is­lands

Once the cuts has been made, hit U on the key­board or se­lect the Un­fold but­ton. This will un­fold the mesh along the seam cuts. Then hit P on the key­board to pack the UV is­lands, or go to the Lay­out global tool­bar at the bot­tom of the screen and click the Pack but­ton.

The re­sult is nowhere near as good as what you’d get with man­ual UV seams, but it’s fast and good enough for what we’re do­ing here. Sub­stance Painter, which is the next step, is very good at han­dling tex­tures across UV seams, so even with a chaotic UV map as this, we should be able to get a good re­sult. Save your mesh and close Un­fold3d. Make a new project, and choose your low-poly model as source. Choose the res­o­lu­tion of your tex­tures. I chose 4,096 x 4,096.

Once in the pro­gram, I choose to bake my map types us­ing the high­res­o­lu­tion model as in­put. I use the stan­dard set­tings which usu­ally work very well for me. Re­mem­ber to match the baked tex­tures to your project tex­ture size, which in my case is 4,096 x 4,096.

ex­port sep­a­rate ma­te­ri­als One of Master­piecevr’s short­com­ings is the cur­rent lack of lay­ers. So once you ex­port some­thing, you’ll ei­ther have to break it into dif­fer­ent el­e­ments in an­other sculpting pack­age, or you can paint in dif­fer­ent ma­te­ri­als in the tex­tur­ing phase. You can also draw in el­e­ments as poly­gon data which will ex­port as sep­a­rate el­e­ments. I use this to draw en­gine glow parts.

20 Ma­te­ri­als

Once you have your tex­tures baked, you can start hav­ing fun with ma­te­ri­als. Re­mem­ber to en­able Mir­ror mode.

By us­ing a com­bi­na­tion of smart ma­te­ri­als, I’m able to quickly get a use­ful base ma­te­rial down. By tweak­ing mask pa­ram­e­ters and com­bin­ing dif­fer­ent smart ma­te­ri­als, it’s pos­si­ble to quickly get away from the pre­set look. Sub­stance Painter has a pow­er­ful group of smart masks that will add ma­te­ri­als to your model ac­cord­ing to ambient oc­clu­sion, edges, sur­face di­rec­tion and so on. You can also choose to paint every­thing from scratch us­ing some of the many brushes.

21 pre­view Ma­te­ri­als

All the way through the process, you can pre­view your ma­te­ri­als in the built-in Fire­fly ren­der. It gives a very pre­cise idea about how your ma­te­ri­als will look once you take the tex­tures out­side of Sub­stance Painter. I use this a lot and play around with dif­fer­ent HDRIS and cam­era ef­fects.

Once you’re happy with the re­sult, ex­port the ma­te­ri­als. I use the ‘Doc­u­ment chan­nels + Nor­mal + AO (No Al­pha)’ pre­set. Depend­ing on what pro­gram you’ll be tak­ing this into, you can choose an­other pre­set or tweak to your heart’s con­tent. Close Sub­stance Painter.

22 cin­ema 4D setup

The last step is setup and ren­der­ing in Cin­ema 4D with Oc­tane Ren­der. Oc­tane is very pow­er­ful, and great be­cause it shows you a real-time ren­der of the changes you make to ma­te­ri­als, lights, cam­era and so on.

Im­port your low-poly mesh by us­ing File>merge. I usu­ally use the stan­dard im­port set­tings. For this project I im­port both the hull mesh and the win­dows/lights mesh. They should align per­fectly.

I then open the Oc­tane Live Viewer so I’m able to pre­view my changes on the go. To get a bet­ter view of the scene, I add an Oc­tane­day­light from the live viewer’s Ob­jects menu. You can change the sun po­si­tion by ro­tat­ing the light gizmo in your view­port.

23 sub­stance Ma­te­rial Im­port

Open Livedb from the Oc­tane Live Viewer Ma­te­ri­als tab. Go to the Misc ma­te­ri­als and find the Sub­stance PBR pre­set. Choose the one with tex­tures on it. It’ll make it eas­ier for you to re­place the pre­set tex­tures with the ones you ex­ported from Sub­stance Painter. This should give you a Mix type ma­te­rial in the Ma­te­ri­als tab un­der­neath your 3D view­port. Drag this ma­te­rial onto your mesh. Dou­ble-click the ma­te­rial and open the Node Ed­i­tor. Now it is sim­ply a mat­ter of re­plac­ing the metal­lic, dif­fuse, nor­mal and rough­ness tex­tures with your own tex­tures.

24 cam­era set­tings

I make a Oc­tane Cam­era through the Ob­jects menu in the live viewer. This makes a stan­dard phys­i­cal Cin­ema 4D cam­era with an Oc­tane cam­era tag. If you click this tag, you can change aper­ture (to add depth of field), add bloom, vi­gnette and change ex­po­sure.

25 emis­sive el­e­ments

To get the win­dows/ lights to emit light, I cre­ate a new ma­te­rial by click­ing the Cre­ate but­ton in the Ma­te­ri­als tool­bar un­der the view­port. Choose Shaders>c4­doc­tane>oc­tane Ma­te­rial. Go to the Emis­sion tab, and add a black­body ma­te­rial. Drag the ma­te­rial to the el­e­ment you want to light, and tweak the set­tings un­til you’re happy with the re­sult in the live viewer. •

scene bounds Re­mem­ber to sculpt as big as pos­si­ble in­side the sculpt area. That way you max­i­mize the amount of de­tail you’ll be get­ting from the res­o­lu­tion you’re sculpting at. If you need de­tail out­side of the scene bounds, use your poly­gon tools! I usu­ally use this for back­ground el­e­ments such as dis­tant mountains.

Martin ne­be­long Martin is a free­lance artist liv­ing in Den­mark. He has been work­ing as a 2D artist for 15 years, but since he got his VR head­set five months ago, 3D is be­com­ing an in­creas­ingly big­ger part of his work. www.art­sta­tion.com/mar­tin­ity

fi­nal space­ship ren­der

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