is possible to play almost any type of game with one button, but it is
rarely convenient or intuitive. On the other hand, it is also easy to
get sloppy and just assign actions to different buttons because it's
the quick and easy solution. Simplicity is often good, but can the
product be designed in such a way where we can be more certain the
player enjoys the experience of playing?
loading the button with more than one function the player can be forced
to make, and commit to, multiple actions at the same time. Actions can
also be distributed over time, or even eclipse actions depending on the
looking into applications, it may be interesting to investigate how a
one button interaction could work with a multi-action toy without being
specific about what the actions might be. If the actions are defined
abstractly as "A" and "B", what ways can the player activate them?
Below is a non-comprehensive list of possibilities:
- Press Button = Activate "A". Release Button = Activate "B"
- Press then Release Button = Activate "A". Press then Release = Activate "B" then cycle back to "A"
- Press Button = Activate "A" and "B"
- Hold Button = Activate "A". Release Button = Activate "B"
- Press then Release Button = Activate "A". Hold Button = Activate "B"
- Press Button = Activate "A". hold Button for more than N seconds = Activate "B"
- Press Button in situation X = Activate "A". Press Button in situation Y = Activate "B"
- Hold Button for less than N seconds = Activate "A". Hold Button for longer than N seconds = Activate "B"
in this short list, there are things like context-sensitive actions,
overlapping actions, actions in series, eclipsing actions and actions
that are explicitly activated at the ends of other actions. Examples of
how these may be exploited are given in the Appendix.
the actions are continuous or act over time, the combinations of
actions increase again. More configurations can be added by making
action "A" last in proportion to the time the button is held. For
instance, in possibility 4, action "A" could still be operating when
the button is released for a time set by the held period. With
possibility 5, the player can choose whether to overlap the functions.
The key with loading is working out what will combine naturally, and what actions you don't want to eclipse others.
Hypothesis: Consistency is more important than simplicity. How does this apply to Button Loading?
look at the second possibility in our list, which is basically a toggle
system. The problem with toggle systems is that they have two states,
and if the player has no feedback, it would be impossible to tell which
of the two actions has been performed. This is different to something
like a jump button: You press jump, and you know the player toy will
jump, even if you can't see it. So, although the toggle system is
logical, and internally, cyclically consistent, it doesn't do the same
action every time you activate it, only every other time.
example of where this can be a problem is on flight simulators. Imagine
playing a flight simulator and there is a key mapped to the
lowering/raising of the undercarriage/wheels. On the instrument panel
there is a button which is also mapped to the key. The button shows a
picture of the wheels in a lowered (ready for landing) position. Does
this mean that the wheels are currently in the lowered position? Or
does it mean that when the button is pressed they will move into this
position? Is this is a problem with the graphic of the button (the User
Interface or UI)?
toggle function has some blame to take in this. As a toggle system
isn't explicit about its state, it is not obvious whether a player is
activating one action or another. If no direct feedback is given, there
is then the UI problem of distinguishing between state and potential
This section is all about jump mechanics
the action of jumping is almost always performed via one button and
there are so many different ways of jumping in computer games, this
seems like a good place to look at some examples and maybe come up with
is a jump? A possible definition is: To move suddenly and in one
motion. Usually jumping is thought of as an upward (and optionally
horizontal as well) motion from a surface (e.g. the floor). But what of
double jumps? Or jumps that push down from a ceiling? For this next
list only conventional "jump from floor up and then fall from jump to
floor" situations are considered.
- Press Button = Jump to fixed height and drop to floor. Release Button = N/A (Manic Miner, Chuckie Egg, Donkey Kong)
- Press Button = Jump to fixed height. Release Button = drop to floor. (unknown)
- Press Button = Jump to fixed height. Press Button again = Jump to extra height – “double jump”. (Devil May Cry, Lego Star Wars)
Button = Jump and continue to add upward thrust with diminishing
returns until maximum jump height is reached. Release Button = cancel
upward thrust resulting in smaller jumps. (Most Mario games, James Pond)
Button = Jump and continue to add upward thrust with diminishing
returns until maximum jump height is reached. Release Button = drop
immediately to floor. (unknown)
- Hold Button = Build Jump power. Release Button = Jump up and/or across proportional to power. (Spiderman, Bugaboo the Flea)
are that you will immediately identify with many of these systems. The
more adventurous modern games often include many extra jump
opportunities by involving other objects, such as walls in Prince Of Persia: Sands of Time.
new games are beginning to employ option 6 as their jump action with
some interesting results. This deserves a special note: with options 6
- or any action that involves charging up – it is very important to
give some visual feedback that it is having an effect. Shooters often
do this with a rather attractive build up of particle effects. Jump and
run games less often show sufficient feedback such exaggerated swinging
of the arms and stooping posture as the jump 'winds up'.
jump is often changed by the motion of the Player Toy before the jump
and often by other control inputs when the jump button is hit. Avoiding
the complexity of adding more buttons for this article and assuming
that a previous action has been executed, what ways can previous
actions have on the character of the jump?
- Horizontal movement is carried over into the jump.
- If the previous position was a duck/crouch the jump is higher
the last action was a jump and the Player Toy landed less than N
milliseconds before then jump higher (somersault with third consecutive
jump – Mario 64)
- If the last action was a jump from the ground, jump again from current position: “double jump”.
- If the Player Toy was shooting, the jump becomes a somersault to maintain target lock and dodge projectiles.
Or, some more experimental ideas:
the Player Toy is locked on to an object or – if a First Person Shooter
game – the view is centred on an object then automatically jump to that
object or intercept it.
the Player Toy is locked on to an object or – if a First Person Shooter
game – the view is centred on an object then jump in an arc over the
object maintaining distance.
- If the Player Toy is rolling along the ground the Jump with more horizontal force than normal.
the Player Toy is running the Jump distance is influence by which frame
of the run cycle the Player Toy is in when the button is pressed.
- Player Toy jump height is proportional to how many meanies are attacking at the moment the button is pressed (similar to Bangai-O's special attack)
Button Loading examples
how might button loading be used? There are a few examples in the
movement section, but just using the list in the Button Loading
section, how might these be used specifically? Of course, the
applications are infinite really, but some examples might provide a
1. (A) as a primer for (B) which can't be canceled once begun. This
might be useful for loading a weapon: drop empty magazine (A), load new
magazine (B). While in most situations you may want (B) to follow (A)
immediately, by separating the actions you can allow new situations to
develop without hindering or confusing the player. Examples: (A) stop
(B) fire, (A) drop guard (B) kick, (A) duck (B) jump.
2. This is really a toggle system. It might be used to raise (A) or
lower (B) an undercarriage for a plane, or lock (A) unlock (B) a car
door. Ikaruga uses this system to switch modes of the ship. If
A continues acting for a period of time B can be used to augment it,
e.g. (A) = jump, (B) = Double jump. This makes it much more than a
toggle system and introduces the rule: B only comes into action if A is
3. Activating 2 actions at the same time will have the effect of making
it seem as if it's just one action, depending on the application. If
the actions are different enough it will probably be more useful to
have the option to activate them separately, however this is still an
option so what can it be used for? What if (A) is a speed modifier
(turbo) and (B) is some sort of force field? This forces the player to
be less at risk when moving quickly. How about if (A) is a forward roll
and (B) is drop a bomb?
- Possibility 4. In Wild Metal (Country),
the Space bar is used to raise the gun turret (A) and when released the
turret fired a shell and the turret lowered (B - combined action, fire
+ lower). A simple, elegant system there. In Prince of Persia: Sands of Time
(A) is the action of wall running, and a few games will have (A) as a
target lock system. In these last two examples (B) is just the action
of canceling (A), but how might these games change if (B) were assigned
a function? What action might be appropriate? And how might it affect
the rest of the game and the level design?
5. Does (B) eclipse (A): that is to say, if (B) is activated does the
(A) action cease? An example of this would be if (A) is jump, and (B)
is drill down. In this case activating (B) might have the effect of
immediately dropping the character out of the air to drill. In this
case, it is unlikely that (B) should always to follow (A). (B) would
activate only if (A) was active. If (B) doesn't eclipse (A), (B) could
be used to augment (A), for instance if (A) is jump and (B) is glide.
Possibility 5 is a variation on Possibility 2, but in this case there
is more control over action (B)
6. Again there is the option of eclipsing (A) with (B), however, here
(A) can be triggered many times before choosing to activate (B). It
also means that the player has to activate (A) in order to activate
(B). (B) also has a specific time cost which could be used to push the
limits of the players skill and timing. With this system it isn't
usually intuitive if (B) eclipses (A) unless (B) could be seen as an
enhancement to (A). The reason for this is that the state of the button
has not changed, so the action should not change. (B) might be best
used then as an augmentation, or enhancement to (A). If (A) is a jump
action again, (B) might be shield activation, or activate rocket pack.
If (A) is firing a shot, (B) might be fire a more powerful shot, or
fire a different kind of shot...
- Possibility 7. This context sensitive action is quite a common device and is used heavily in Conker's Bad Fur Day.
Typically a player toy will have an "action" key assigned to it which
triggers different actions in specific places which are marked on the
playfield. It is also used in combat systems to change the type of
attack depending on factors such as relative positions (and attitudes).
Or it can be based on rule conditions, such as: Player Toy has Ball
then (A) = kick ball; Player Toy doesn't have ball then (B) = tackle.
It could be argued that this is not a very consistent system,
especially when based on playfield location, but really this depends on
the type and scope of actions. This possibility encompasses many of the
others as context can also be button state and/or time eclipsed.
8. When the button is pressed, the player is committed to action (A) or
(B). But in this case (B) could be do nothing, in which case, there is
an unusual decision for the player: If quick action is needed, they
must decide whether to activate (A) so that another action can be
performed, or cancel (A) by selecting (B) which costs time. If (A)
costs resources other than time, this immediately puts the player in a
dilemma. A simple example: (A) is shoot, (B) is cancel. The player is
faced with a target to shoot, as they press the button, the target
covers itself with something valuable to the player. At the same time
another hostile target appears. The player has a number of options: 1.
shoot the valuable and then both targets, 2. Cancel and then shoot the
new hostile target (risking that in that time they don't get shot
themselves), 3. try and line up with the hostile target and fire before
the switch to (B) happens. (B) can also be an enhancement of (A) which
will give us a simplified version of the R-Type firing mechanic seen in
the last interactive example in the section on attacking. This system
can also employ eclipsing and layering of action (multiple actions
happening at the same time) depending on how long actions (A) and (B)
take to complete.
Playfield: The physical and/or logical areas of play (eg. A spooky castle)
Toy: A focal point of attention and imagination. These are the interactive elements of/in/on the playfield (e.g. A robot)
Player Toy: The player's representative in the playfield (e.g. Hero)
Meanie: A Toy that is aggressive towards the player toy (e.g. a mutant monkey)
Toy Set: The set of all interactive elements
Action: A feature of the toy (e.g. Jumping)
Activity: The result of using the toy's action on another toy or the playfield (e.g. jump over robot or up spooky stairs)
Challenge: A defined goal - by the player or designer - or objective (e.g. kill robot or get to the top of the castle)
Natural rules: Rules inherent to the environment (e.g. collision, gravity, light)
Supernatural Rules: Rules that dictate the laws and logic of the game (e.g. If Robot hits the hero, the hero will die)
[Special thanks to Gary Penn for his help with this article.]