Gamasutra is part of the Informa Tech Division of Informa PLC

This site is operated by a business or businesses owned by Informa PLC and all copyright resides with them. Informa PLC's registered office is 5 Howick Place, London SW1P 1WG. Registered in England and Wales. Number 8860726.

The Metrics of Space: Tactical Level Design
September 21, 2019
Press Releases
September 21, 2019
Games Press

If you enjoy reading this site, you might also want to check out these UBM Tech sites:

# The Metrics of Space: Tactical Level Design

[Design]

September 4, 2012 Page 3 of 5

# Player Psychology: Correction Cycles

Humans are excellent "guesstimaters." We tend to iteratively guesstimate our way to the solution of problem by continually guessing, observing, and correcting. Imagine you are reaching out for your cup of coffee. You will move your hand, observe its new position, and then update the amount of movement required to meet with the target. This will happen many times per second until you reach your goal. (Figure 14) (This is akin to Steve Swink's "delicious cupcake" example in Game Feel.)

Figure 14

Basically, the more we expect the player to change their position or line of sight, the more correction cycles we are forcing them to undertake. The lower the number of correction cycles, the easier it is for the player to hone in on their target.

Figure 14 is an example of our guesstimation process when honing in on a static target. The large red triangles represent the margin for error in any guesstimation phase; the larger the triangle, the more room for error in that guesstimation step.

As we hone in on our target via movement, observation, and correction (update), we gradually reduce our margin of error. However, if an object continues to move, then the amount of possibilities will not reduce in a linear fashion, like Figure 14 suggests.

To give another example, let's assume that the player is undertaking the same process of move, observe, update for a static object -- say they are trying to adjust their crosshair so it is over a target. They will gradually move the crosshair until the margin of error becomes lower and lower via this process of refinement.

Now, imagine of the target suddenly reacts to the player and attempts to evade them via strafing away (Figure 15). The player will now need to significantly update their process of guesstimation, bringing more possibilities, and hence a greater margin for error, until they eventually hone in on the enemy again.

Figure 15

# Evasion Vectors

Although open spaces open up the possibility for the player to be flanked or approached from many more approach vectors by enemies, more open spaces also allow the opportunity for evasive maneuvers by the player.

In Figure 16, the player has the advantage, as there are more evasion vectors than enemy approach vectors. In a previous article where I dealt with the notion of compression and funnelling, I refer to these vectors as "expansion vectors" -- an element which can alleviate the tension caused by compression via enemy encroachment on the player.

Figure 16

In the majority of cases, players in first person perspective games will choose to firstly adjust their world position so that as many enemies as possible can be kept in the current view perspective -- watch someone play Serious Sam and they will usually prefer to backpedal away from enemies so they can keep their view frustum on them. World movement change is preferred above excessive view frustum changes. In most cases, a player will choose to backpedal first with minimal changes to view position. (Figure 17)

Figure 17

In a tactical scenario, strafing around an enemy will always be advantageous, as enemies require more correction cycles to attack a strafing target as opposed to one that is simply moving away or towards them. You can think of this in terms of the movement of a crosshair in game. If a player backpedals away from their enemy, then although they are becoming a smaller target, the amount of correct cycles required to adjust the cross-hair is significantly less. (Figure 18)

Figure 18

When an enemy moves in such a way that it causes the player to frequently update their view frustum, the scenario is much more difficult due to the margin of error which is being introduced into the scenario. (Figure 19)

Figure 19

# Level Geometry and Player Tactics

Now that we have an understanding of the essential metrics and player psychology, we can now look at how level geometry begins to modify these relationships from both a difficulty perspective as well as an emotional perspective.

Figure 20 is a simple depiction of how level geometry begins to modify the player's the emotional state and strategy by affecting the view frustum. Frame 1 of Figure 20 shows an artificial representation of the player's view frustum, whilst frame 2 depicts the actual view frustum after occlusion.

Figure 20

Page 3 of 5

### Related Jobs

University of Exeter — Exeter, England, United Kingdom
[09.20.19]

Serious Games Developer
Sucker Punch Productions — Bellevue, Washington, United States
[09.19.19]

UI Artist
Cold Iron Studios — San Jose, California, United States
[09.19.19]

Senior Content Designer
Deep Silver Volition — Champaign, Illinois, United States
[09.17.19]

Environment Artist