Sculpt SCI-FI CONCEPTS IN vr
Freelance illustrator Martin Nebelong demonstrates how to quickly model sci-fi concepts in VR
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.