Before a 3D environment becomes detailed and polished, artists first establish its basic structure through blockout. Using simple shapes, they define scale, proportion, composition, and spatial relationships. This early stage provides a flexible foundation for experimentation, helping artists identify problems, test ideas, and build stronger environments before adding detail.
WHAT IS A 3D BLOCKOUT
In honor of Blocktober I thought I would just do a quick video on what blockouts actually are.
01 A 3D blockout is a simplified version of a 3D environment, object, level, or scene built from basic shapes. The goal is not to make something look finished. Instead, a blockout helps you figure out size, shape, proportions, composition, and spatial relationships before spending time on detailed modeling, materials, lighting, or decoration.
02 Think of it as building the skeleton of a 3D scene.
03 A blockout might use nothing more than cubes, cylinders, planes, and simple extrusions. Despite its simplicity, it can answer important questions early:
- Is the room large enough?
- Does the character have enough space to move?
- Does the composition look good from the camera?
- Are the important objects in the right places?
- Does the level’s layout make sense?
- Are the proportions believable?
Making these decisions early is much faster than discovering problems after you’ve created a highly detailed model.
BLOCKOUT, GREYBOX, AND WHITEBOX: WHAT DO THEY MEAN
04 You’ll often hear blockout, greybox, and whitebox used interchangeably. They all describe an early stage of 3D development, but their meanings can vary between studios and workflows.
05 Blockout
A blockout is a rough 3D representation made from simple geometry.
The emphasis is on ideas and proportions, rather than visual detail.
For example, if you’re designing a room, your blockout might contain:
- A cube representing the room
- Thin boxes representing walls
- A box representing a table
- Cylinders representing columns
- A simple character model for scale
At this stage, you might constantly move, resize, duplicate, or delete objects.
The question you’re asking is: “Does this basic idea work?”
06 Greybox
A greybox is a blockout presented using simple, usually neutral materials—traditionally grey—to make the overall space easier to read.
The term is especially common in game development, where designers use simple geometry to test a level before artists create the final environment.
A greybox might include:
- Basic walls and floors
- Simple platforms and stairs
- Doors and openings
- Cover objects
- Basic collision geometry
- Placeholder props
- A player character or character proxy
The question becomes: “Does this space work when someone actually uses it?”
For a game level, that can mean testing movement, sightlines, combat encounters, navigation, jumping distances, and pacing.
07 Whitebox
Whitebox is another term for an early, simplified 3D environment. It traditionally refers to building a scene from simple white or untextured geometry.
In some workflows, “whitebox” emphasizes the construction of the physical space, while “greybox” emphasizes testing and gameplay. In others, the terms are simply used as synonyms.
There is no universal industry-wide distinction between greybox and whitebox. Different studios and artists may use the terms differently.
A useful way to think about them is: Blockout → Greybox/Whitebox → Detailed/Final Asset
But these stages can overlap, and a project may use only one of the terms.
WHY MAKE A 3D BLOCKOUT
08 The biggest advantage of blockout work is speed.
Imagine you’re modeling a building and spend two days creating detailed walls, windows, doors, trim, and materials. You then realize that the rooms are too small and the main hallway doesn’t work.
You now have to remodel a lot of finished work.
With a blockout, changing the hallway might take thirty seconds.
That’s why blockouts are useful for answering difficult questions before committing to detail.
09 1. Test proportions
A blockout lets you compare objects against one another.
For example:
- Is the doorway wide enough?
- Is the ceiling too low?
- Is the chair the right size compared with the table?
- Is the building appropriately sized compared with a person?
Using a simple character or measurement reference can make these problems obvious.
10 2. Test composition
If you’re creating an environment for a film, animation, or game, you can use the blockout to establish the composition.
Set up a camera and ask:
- What does the viewer see?
- Where does the eye go first?
- Are important shapes visible?
- Is the silhouette interesting?
- Is anything blocking the subject?
You can solve many composition problems before modeling any detailed assets.
11 3. Test scale
Scale is one of the most important things to establish early.
A staircase that looks reasonable by itself might turn out to be enormous when compared with a character.
Adding a simple scale reference—such as a human character, ruler, or known-size object—helps keep the scene believable.
12 4. Test functionality
For games and interactive experiences, blockouts allow designers to test whether a space actually works.
You can test:
- Player movement
- Jump distances
- Navigation
- Visibility
- Combat spaces
- Doorways
- Cover
- Traversal routes
- Camera placement
If the basic geometry doesn’t support the intended experience, adding detail won’t fix the underlying problem.
HOW TO MAKE A 3D BLOCKOUT
13 The exact process depends on the project, but the following workflow works well for most environments.
14 Step 1: Start with the big idea
Before modeling anything, identify the major shapes and spaces.
For example, suppose you’re blocking out a small medieval courtyard.
You might identify:
- Main building
- Courtyard
- Gate
- Tower
- Stairs
- Fountain
- Player path
Don’t worry about bricks, roof tiles, decorations, or materials yet.
You’re establishing the large-scale structure.
15 Step 2: Establish scale
Bring in a reference for scale.
In a game environment, this might be the player character. In an architectural scene, it could be a human figure or known measurements.
Check things such as:
- Door height
- Ceiling height
- Stair dimensions
- Furniture size
- Hallway width
- Distance between buildings
Don’t wait until the final modeling stage to discover that everything is the wrong size.
15 Step 3: Use primitive shapes
Start with basic primitives such as:
- Cubes
- Spheres
- Cylinders
- Planes
- Cones
A cube can represent an entire building. Another cube can represent a wall. A cylinder can represent a column.
The shapes don’t need to resemble the final objects yet.
A blockout is successful when the relationships between the shapes communicate the design.
17 Step 5: Add important secondary forms
Once the primary forms are working, introduce elements that affect the space.
For example:
- Windows
- Doorways
- Stairs
- Platforms
- Large furniture
- Pillars
- Bridges
- Railings
These don’t need to be final-quality assets. They simply need to communicate how the space is organized.
18 Step 4: Establish the camera
If the scene will be viewed from a specific camera, set it up early.
Move around the blockout and look at it from the intended viewpoints.
This can reveal problems that aren’t obvious from a free-floating perspective.
For example, a building might look interesting from above but completely block the subject from the actual camera.
19 Step 7: Test the blockout
Now interact with the scene or examine it from the intended viewpoints.
Ask: “Does the space work?”
For an environment, check the composition and scale.
For a game level, test movement and gameplay.
For an animation, check camera angles and character staging.
For an architectural visualization, check whether the proportions and circulation make sense.
20 WHAT SHOULD YOU NOT DO DURING BLOCKOUT
A common beginner mistake is adding detail too early.
21 You generally don’t need to worry about:
- Detailed textures
- Small bevels
- Screws and bolts
- Decorative trim
- Small props
- Complex materials
- High-resolution sculpting
- Final lighting
- Tiny surface imperfections
22 If you’re spending several hours modeling a tiny detail during the blockout stage, ask yourself whether that detail actually helps answer a design question.
If it doesn’t, leave it for later.
THE MOST IMPORTANT PRINCIPLE
23 A 3D blockout isn’t supposed to look impressive.
It’s supposed to make decisions cheap.
If you can discover that a room is too small by moving a cube, that’s much better than discovering it after you’ve spent hours creating a detailed environment.
24 So when you’re blocking out, focus on the questions that matter most:
What is the space? How big is it? Where are the important things? How does someone experience it? Does the overall design work?
Once those answers are solid, the detailed modeling becomes much easier—and much less likely to need major revisions.
25 Blocktober runs from October 1 to October 31 each year.
CONCLUSION
3D blockouts provide the foundation for successful environments by focusing on scale, composition, proportion, and movement before detail. By working with simple shapes, artists can experiment freely, identify problems early, and make confident decisions. A strong blockout saves time, supports creativity, and ensures the final environment communicates its intended purpose.