Scale and proportion

Scale is how big something is, or looks, relative to the player. Proportion is how the parts of a thing, or the things in a scene, relate in size to each other. Players read both instantly and without thinking: a door that is a little too big, or a chair that is a little too small, makes a scene feel wrong before anyone can say why.

This page covers scale as an art fundamental: how players judge it, how to keep it consistent and when to break it. Units, export settings and real-world measurements are in units, scale and axes; gameplay dimensions are in grids and metrics.

#How players judge size

People judge size by comparison. With nothing familiar in view, a wall could be 3 m or 30 m tall. A door, a stair, a window or a person gives the viewer a reference to measure against.

The most useful rulers are things everyone knows the size of:

• People. The most direct scale reference.
• Doors, stairs and railings. Built to fit the human body.
• Everyday objects. Chairs, bottles, crates, vehicles, cables.
• Repeated architecture. Floors of windows, bricks, tiles.

This is why environment artists keep a figure in the scene. Jared Sobotta writes: "Having scale reference in your scene while you are building is a must!", and "a good scale reference would be a mock up average character size" (CGSociety: How to Create a Stunning Portfolio with Jared…; ArtStation: CGSociety Interview "How to Make a Stunning…). Andrew Lund III did the same in his winter street: "I referenced everything against a scale figure" (80 Level: Winter Street Scene: Environment Production…).

#Consistent scale within a scene

A world can be big or small, but it has to agree with itself. Sobotta warns: "If one piece of your overall scene is out of sync with the rest, it will catch the viewer's eye" (CGSociety: How to Create a Stunning Portfolio with Jared…). This is unwanted unless the odd object is meant to be the focal point.

Common sources of inconsistency:

• Assets from different sources. Kit pieces modelled at different unit scales. See units, scale and axes.
• Texel density mismatches. A crate with huge wood grain next to a wall with tiny bricks reads as a scale error even when the meshes are correct. See texel density.
• Detail at the wrong size. Bolts, bevels and cracks that would be enormous in real life.
• Scaling meshes in the engine. Uniformly scaling a prop to fill a gap changes the size of every detail on it.

#Game scale compared with real-world scale

Real proportions are a starting point, not a rule. The Level Design Book notes that level design usually follows "real world architecture built at a human scale", but advises you to "build at the player's scale" and even "Don't follow real world scale" (The Level Design Book: Metrics). It explains that "Video games often rely on an exaggerated sense of scale that does not correspond to any consistent real world measure", and that "big" levels are usually much smaller than their real-world equivalents (The Level Design Book: Metrics).

There are two main reasons:

• The player's body is bigger than the model. "Bounding box / collision sizes are usually much bigger than the actual character model" (The Level Design Book: Metrics). Corridors, doors and stairs grow to fit. See player collision capsule.
• The camera changes perceived size. Camera height is "one of the key variables that affect the player's sense of a virtual body", and a high field of view zooms out and distorts the edges of the screen (The Level Design Book: Metrics). Wider FOVs add perspective distortion; narrower ones flatten it (Valve Developer Community: Field of View). See cameras, lenses and field of view.

#Exaggerating scale on purpose

Once scale is consistent, you can break it deliberately.

#Size and attention

Piaskiewicz lists scale among the main eye-catchers: "Bigger composition elements will get more attention than the rest of the scene", citing a giant building construction in Crysis 3 (Game Developer: Composition in Level Design). He also describes camera angle: seen from below, the dominant "is literally dominating the composition" (Game Developer: Composition in Level Design). A tower, statue or tree that is far larger than its neighbours becomes a landmark.

#Scale and mood

Huge spaces can feel awe-inspiring, empty or threatening. Small, low spaces feel intimate or oppressive. On The Last of Us Part II, early concept work explored "how much we want to push the overgrowth, scale, and destruction types for the environments of the game" (Cook & Becker: Art directing The Last of Us Part II). Scale was one of the settings used to define the tone of the whole world.

#Forced perspective

Theme-park designers make buildings look bigger than they are by shrinking details towards the top. Disneyland's Sleeping Beauty Castle is 77 feet (23 m) tall but uses forced perspective so that "design elements are larger at the foundation and smaller at the turrets" (Wikipedia: Sleeping Beauty Castle). The same technique works in a game for distant backdrops and skyline buildings: smaller windows and bricks up high make a building feel taller. It only works from the intended viewpoints, so check it from every place the player can stand.

#Proportion within an object

Proportion also applies inside a single asset. Thick versus thin, wide versus tall and the ratio of big to small forms decide whether a prop looks sturdy, delicate, cartoonish or realistic. Exaggerating proportions (chunkier doors, bigger handles, thicker trims) is one way to keep a stylised asset readable at a distance. The ideas of primary, secondary and tertiary forms in primary, secondary and tertiary forms are a good tool for checking proportion: the biggest forms should dominate, and small detail should stay small.

#Related pages

units, scale and axes · grids and metrics · player collision capsule · texel density · cameras, lenses and field of view · landmarks · focal point · primary, secondary and tertiary forms · gathering and using reference

#Further reading and watching