This tutorial was written by the amazing Zacharias Reinhardt and appeared in issue 100 of 3D Artist
Tools used
Blender
Photoshop
In this tutorial we will create a complex robot vehicle scene. We will use Blender as our tool, Cycles as our render engine and Photoshop for post-processing. We will also take a look at paid Blender plugins and products that will help to save us a tremendous amount of time – in particular, these include the Cycles Material Vault (CMV), The Grass Essentials and The Grove 3D. First we'll cover how to easily design a believable sci-fi vehicle and how to translate it into 3D using a simple blockout. After that we will replace the blockout parts piece by piece with high-resolution elements. For creating these elements, we will cover different approaches to hard-surface modelling in Blender. This will be interesting, because the vehicle consists of three completely different parts (the car, trailer and robot legs). Then we will shade it, using and customising shaders from CMV. A simple HDRI setup will help us to light our scene. A minimalist environment and additional elements will help us to tell a story around our main object. Then, with some post effects, we will finish our render.
Step 01 – A simple recipe to design a sci-fi vehicle
Here is an easy way to design a sci-fi vehicle: take a vehicle that you like (in this case a Lada Niva) and then leave the main shape as it is or combine it with another completely different vehicle or machine that exists in reality (like a trailer, in this case). At final stage we can add robot legs or other sci-fi wheels or nozzles. With this simple guide, we can create tons of different interesting sci-fi vehicles. Imagine combining a sports car with a tank or a baby carrier with robot legs!
Step 02 – Visualise the vehicle design
Mischief is a useful tool for sketching out ideas. For creating a design like in Step 1, there are a lot given elements from the different vehicles, so we need to focus on how everything is combined and add in believable sci-fi elements. We can grab parts from other machines and vehicles and add them to our creation, and we can add objects that we use day to day to make it more believable. In this render, a suitcase, a boot, a towel and a water can were added to purvey a sense of reality.
Step 03 – Block out the vehicle in 3D
Creating a simple 3D blockout, we have much room for research and testing. Now we will see if our concept works in a space with real measurements and perspective. We can use a simple 3D character to check the vehicle's size and if a human could interact with it. It's no big deal if we delete or replace objects we don't like, but we should always check if the proportions of the different parts fit together. This blockout will serve as the basis for the final model. We will use this as the foundation and replace the low with the high-resolution parts step by step.
Step 04 – General hard-surface modelling techniques
The fewer polygons we have to take care of in the Edit mode, the less trouble we will have. We'll use modifiers to add higher quality to low-resolution objects. For our vehicle we will use two main modifier setups. The first is for objects with volume. A Subsurf modifier plus a Mirror modifier (if things should be mirrored) will do the job. This gives us the freedom of combining smooth and hard surfaces by adding Loop Cuts. The second setup is used for flat surfaces with a slight thickness, such as bodywork. We'll use the same setup as before, plus a Solidify modifier and a Bevel modifier.
Step 05 – Model the body of the car
For modelling real cars we can add blueprints (which are available online from www.the-blueprints.com) as background images. Be sure to add at least a front and a side view. The images should align together perfectly. In most cases a Plane is a good object to start with. We can use the second modifier setup for thick surfaces. Now we can start modelling the body, according to the blueprint. Start positioning the Plane in Edit mode and extrude new faces along the main features of the body. Try to add Loop Cuts in the right positions to add holes for things, such as for the headlights. A car body consists of different pieces – it is helpful to model all parts separately.
Step 06 – Model the body of the trailer
For the trailer we need to model one side, adding a Mirror modifier and extruding it to the centre to close the rest of the gap. Now the Subsurf modifier and Loop Cuts will help us to define the shape. For the trims and the seals, add a simple shape on top of the surface and use a Subsurf and a Solidify modifier for the thickness. Remember to cut holes for windows, the door and where the trailer and car will be joined together. Use the cut-out elements for the glass and the door.
Step 07 – Model the legs
The legs are the only parts that are completely fictional. Here it might be useful to paint an extra concept or a 3D blockout for the functionality. The robot legs are roughly built up like a human or animal leg – the inner part is like the bones, the pistons are like the muscles, while the cables are like the veins and the bodywork is like the skin. Make sure that the legs are heavy and strong enough to carry the whole vehicle. To speed up the modelling process, model everything in one object, copy faces or whole elements and re-use them for other parts. For the armour, simple flat faces are enough if we use the Solidify modifier method.
Step 08 – Model the feet
Re-using elements for another purpose is a great way to add interesting details. Here, a tyre was reused for the feet. Create one segment of a tyre, mirror it, and duplicate it along a curve using an Array and a Curve modifier. After applying all modifiers, we can cut it into pieces, which we can use for the feet. After one leg is finished, we can copy it to the back. Here the vehicle is heavier, so increase the size of the leg. It's worth changing the model a bit here so that it doesn't look too much like it was copied.
Step 09 – Add bolts
Bolts are a simple but effective way to add finer details to our legs and other parts of the vehicle. Model a simple bolt head and place the origin at the bottom. With the Snap option (Snap Element>Face) and Align Rotation With The Snapping Target enabled, we can move the bolt onto the surface of other objects. Now we can duplicate the bolt all over the leg and vehicle.
Step 10 – Add the details
We have to think about where adding details supports the main subject and invites the viewer's eye to linger for longer. All the tiny elements need to make sense. We shouldn't add details just because they look cool – we should add them because they have a function, such as lamps, an exhaust and cables. Create your cloth objects like the sunshade and towel using the cloth simulation and pinned vertices. To add to the overall used look of the car, add a Displacement modifier using a simple procedural Clouds texture to the body and armour. This will add tiny dents to it.
Step 11 – Add cables and ropes
Cables and ropes are a great way to add dynamic elements, which will add plenty of smaller detail where there simply isn't much to be found. In Blender, make use of curves (Path) for this purpose. For a cable with a smooth surface, set the Fill mode to Full (Object Data>Shape) and increase the Bevel Depth (Object Data>Geometry) of the curve. In Edit mode, adjust the shape and duplicate the whole cable. For cables with a individual surface, duplicate one segment using the Array modifier and shape it along a curve using a Curve modifier.
Step 12 – Connect the different parts
A simple trick to combine the trailer with the car and hide any holes is to implement cloths. Model simple quad meshes to fill the holes and add a Multiresolution modifier. Increasing the subdivision of this modifier, we can add folds using the Sculpt mode. Use the SculptDraw brush for the areas between the folds and the Inverted Crease brush to give the folds a little more sharpness.The Solidify modifier adds thickness to the cloths. To hide parts where the legs and the engine are connected and the base is open, we can add even larger surfaces.
Step 13 – Sculpt the environment
An environment does not need to be epic to be interesting – we simply have to place our main subject in a surrounding that we're familiar with. Here, our vehicle has been placed in a field near a forest. First of all, choose the camera position, then add a Plane inside the frame and start shaping it in Sculpt mode. After we have edited the main shape, add a Subsurf modifier to add extra subdivisions. With a Displace modifier using a Clouds texture, we can add tiny bumps to the surface, for higher level of detail. For the background, add another simple Plane, which will cast ground shadows from the trees.
Step 14 – Set up shaders using CMV
The Cycles Material Vault (www.cyclesmaterialvault.com) is a really great paid product to speed up the shading process. It comes with over 100 Cycles shaders and great documentation on how exactly to use it to make the most of them. It allows us to import shaders and adjust them using sliders. For even more control, we can even adjust the whole node tree. Many of these shaders don't even need a UV map. For our scene we can prepare a few shaders that we can use over and over again. In this case, these would include a scratched car paint, rubber, metal, glass, soil and wood, among others.
Step 15 – Add trees and grass
The trees in the background can be created using the paid Blender add-on The Grove 3D (which is available from www.thegrove3D.com). It allows you to grow trees of varying ages, starting with a small sapling. It also gives us plenty of options to let nature take its course to grow realistic trees very quickly. The twigs of different species, which can be purchased separately, add the final touch to the trees. For adding grass we can use the The Grass Essentials (which can be found on the Blender Guru website at www.blenderguru.com). It offers a variety of grass and weeds to create lawns, meadows and fields. With a few clicks, we've added realistic grass to our scene.
Step 16 – Add story elements
To add life to our scene, we can add a dog and birds. Here, we'll use an image of a dog's head, project it onto a simple model and add Hair particles. The same method can be used for the birds. This is a fast way to create background characters. We can add a seat on the top of the trailer in order to make the environment feel more alive. Adding in an old fence in front of the vehicle really adds to the scene's charm.
Step 17 – Render and post-processing
We'll be rendering using the Cycles renderer in Blender. For the lighting, add an HDRI map (www.hdrihaven.com) to the background, which will provide realistic lighting. We can add additional spot or area lamps to highlight areas of interest. Render the scene with a transparent background (1), an Ambient Occlusion pass (2) and a Mist pass (3), then combine everything in Photoshop (4). The Mist pass can be use for fog (A), while the AO pass adds stronger shadows to the scene. The background should be filled with a morning sky photo. For the smoke, use a smoke photo from www.textures.com and apply it over the top of the render, with the Blend mode set to Screen (B). For the warm colour, add an orange-to-blue gradient with the Blend mode set to Hard Light. For the final touch, add an image with tiny white dots to fake small dust particles, as well as some chromatic aberration (C). Done!
Source: www.bing.com
