Sci-fi concept design using displacement maps in Blender

Introduction

In this tutorial I'll be using a base mesh created in a polygon modelling software, in this case Blender, and import it to Octane Render so we can use the displacement maps material  feature to design the details and finish it off in Photoshop. You'll need basic modelling skills and some experience with Octane and Photoshop.

Preliminary design with thumbnails

Starting your project with a few thumbnail sketches saves a lot of time and also allows for some experimentation as you focus entirely on the design. You may already have an initial idea of the world you're building or still just looking to define it, but you can always try out a few different options very fast and cheap.

Defining the early stage design with fast thumbnail sketching

Modeling the basemesh: starting with a plane

After I have a clear idea of the design and where I plan to take it I bring it over to Blender to do some very simple and quick modeling. Although these are very simple techniques this is where I take the more important design decisions. It comes down to deciding which volumes are more important to serve the image and where I can improve on the work done on the thumbnail sketch.

Starting of the base mesh with a simple plane

Modeling the basemesh: slicing and extruding

I start to slice and design the shapes using the Boxcutter add-on for Blender. I use it just for a matter of speed so if you don't have it and don't want to get it just use the knife tool (K) for the same effect. Afterwards I extrude the shapes and work the edges either sliding or moving them, designing all the features.

Using Boxcutter to design the shapes

Modeling the basemesh: UV's and assigning materials

After that I very quickly UV unwrap the model. As Octane displacements only work on models with UV maps this is a crucial step. Here you can decide to have different UV maps for different parts of the model, or keep it all the same. For this image I prefer to use one UV map and just separate the model assigning different materials to the features I want to separate and use different displacements.

Separating the materials by color

Setting the scene in Octane

When I'm happy with the design and the separation of the materials I export the model as an OBJ and import it to Octane. I start setting the scene with a very basic daylight but trying to find a good light direction. I also try to match the design on the thumbnail sketch as much as possible regarding the camera and perspective, but always trying to improve on it.

Starting the scene with basic camera position and daylight

Displacement maps in Octane

In this stage I start to work the materials for the different parts of the design. I separate the features by color also and start to work the details with displacement maps. For this image, I used maps from Jama Jurabaev and Julien Gauthier that you can find on their Gumroad pages, you can also make your own maps of course. Normally I duplicate the objects and keep adding different maps. I added also some normal and bump textures for extra detail, and used a dirt texture node to add some rust/dirt look to the materials.

Detailing with displacement maps

Add decals in Octane

I wanted to add a few decals to some of the materials in Octane, so I used the add texture node to bring some previous decals designed in Photoshop. I tried not to overdo it and keep in mind that I would work these, and some smaller ones in the paintover.

Adding textures as decals

Painting in the rust and wear

After exporting the main render and a extra few passes (zdepth, material ID and object ID) to help me with the compositing. I started to organize the layers in Photoshop and begin what is the most costly part of the process time-wise. Which is adding some extra decals, painting all the rust and dirt, adding the wear to the decals. I also used some photographs to bring in details to the inside part of the structure, as I was going for this really busy and sleek contrasting look with the outside.

Painting rust and adding detail with photos

Finalizing the image

When I was happy with the details I painted in some atmosphere considering the location and direction of light. Added some smoke and dust to bring some life to the image. I played with the color balance and the levels until I was happy with it and ready to call it done.

Finalizing with atmosphere and light effects

Top Tip: Experimentation is profit

Don't be afraid to experiment solutions you never tried before. Sometimes even trying different points of view or camera lenses can give you a whole new perspective of the image you're building.