Chapter 4: Time and Plot

§4.1. The Passage Of Time; §4.2. Scripted Scenes; §4.3. Event Scheduling; §4.4. Scene Changes; §4.5. Flashbacks; §4.6. Plot Management

arrow-up-left.pngContents of The Inform Recipe Book
arrow-left.pngChapter 3: Place
arrow-right.pngChapter 5: The Viewpoint Character
arrow-down-right.pngIndexes of the examples

§4.1. The Passage Of Time

A game that makes heavy use of time may want to give the player a hint that time is important - and an easy way to keep track of how it's going - by adding the current time to the status line, instead of the score. To do this, we would write

When play begins: change the right hand status line to "[time of day]".

All else being equal, time passes at a rate of one minute per turn. But this need not be so: we can imagine a game where turns take much less time, or much more; or a game in which the passage of time was sometimes suspended, or one in which different actions required different amounts of time to perform.

Situation Room provides a way to print 24-hour time, while Zqlran Era 8 implements a completely new measurement of time, for a game set on an alien world.

Uptempo and The Hang of Thursdays speed up time's passage: turns take fifteen minutes in the former, or a quarter day in the latter.

Timeless makes certain actions instant, so that they don't count against the clock; this is sometimes useful in timed situations where the player needs to review the situation before going on with a tricky puzzle. Endurance systematically extends this idea to allow us to assign different durations to any action in the game. The Big Sainsbury's goes the opposite direction, and meticulously adds a minute to the clock for all implicit take actions, just so that the player isn't allowed to economize on moves.

An alternative approach to time is not to tell the player specifically what hour of the day it is at all, but to move from one general time period to another as it becomes appropriate - when the player has solved enough puzzles, or worked his way through enough of the plot. To this end we might use scenes representing, say, Thursday afternoon and then Thursday evening; then our scene rules, rather than the clock, would determine when Thursday afternoon stopped and Thursday evening began:

Thursday afternoon is a scene. Thursday evening is a scene.

Thursday afternoon ends when the player carries the portfolio.

Thursday evening begins when Thursday afternoon ends.
When Thursday evening begins:
    say "The great clock over St. Margaret's begins to chime 6.";

Though this gives time a loose relation to the number of turns played, it feels surprisingly realistic: players tend to think of time in a game in terms of the number of significant moves they made, while the random wandering, taking inventory, and looking at room descriptions while stuck don't make as big an impression. So advancing the game clock alongside the player's puzzle solutions or plot progress can work just as well as any stricter calculation.

* See Passers-By, Weather and Astronomical Events for cycles of day and night scenes

* See Waiting, Sleeping for commands to let the player wait until a specific time or for a specific number of minutes

* See Clocks and Scientific Instruments for clocks that can be set to times and that have analog or digital read-outs

* See Timed Input for discussion of extensions allowing real-time input


arrow-up.pngStart of Chapter 4: Time and Plot
arrow-left.pngBack to Chapter 3: Place: §3.9. Passers-By, Weather and Astronomical Events
arrow-right.pngOnward to §4.2. Scripted Scenes

*ExampleSituation Room
Printing the time of day in 24-hour time, as in military situations.

*ExampleThe Big Sainsbury's
Making implicit takes add a minute to the clock, just as though the player had typed TAKE THING explicitly.

*ExampleUptempo
Adjust time advancement so the game clock moves fifteen minutes each turn.

*ExampleTimeless
A set of actions which do not take any game time at all.

Here we move to a systematic way of giving different durations to different actions, including even variations on the same act -- so that for instance climbing a steep hill might take several minutes more than other going actions. We do this by setting a number, "work duration", to represent the number of minutes consumed by a given action, and then consulting a rulebook to find out how long the past turn's action should take. By default, an action will take 1 minute.

We'll start by emulating the behavior of "Uptempo": each turn we'll set the clock forward most of the way, then check to see what has changed since the last turn, print any relevant events, and only then set the clock forward the final minute. The exception is when an action is set to take no time at all; in that case, we'll skip the rest of the turn sequence rules entirely.

paste.png "Endurance"

Work duration is a number that varies.

Every turn:
    now work duration is 0;
    increment the turn count;
    follow the time allotment rules;
    if work duration is 0, rule succeeds;
    increase the time of day by (work duration minutes - 1 minute).

The time allotment rules are a rulebook.

A time allotment rule for examining or looking:
    now work duration is 0;
    rule succeeds.

A time allotment rule for going:
    now work duration is 2;
    rule succeeds.

A time allotment rule for going up:
    now work duration is 5;
    rule succeeds.

A time allotment rule for waiting:
    now work duration is 10;
    rule succeeds.

The last time allotment rule:
    now work duration is 1.

When play begins: now the right hand status line is "[time of day]".

The Quai is a room. "An attractive park at the edge of the river Aude: here you can wander among palm trees, and watch cyclists go by on the bike path; in the water there are ducks. In the cafe to your north, patrons sip their pastis; and above you is the medieval walled city and its castle."

The Cafe is north of the Quai. "A charming collection of umbrella-shaded tables, from which one can watch the river and the walls of the city beyond. The noise of traffic is only a minor distraction."

The City is above the Quai.

After going to the City:
    say "You struggle uphill for some distance...";
    continue the action.

At 9:15 AM:
    say "The bells ring out from Place Carnot."

Test me with "z / n / s / u".

**ExampleEndurance
Giving different actions a range of durations using a time allotment rulebook.

Here we move to a systematic way of giving different durations to different actions, including even variations on the same act -- so that for instance climbing a steep hill might take several minutes more than other going actions. We do this by setting a number, "work duration", to represent the number of minutes consumed by a given action, and then consulting a rulebook to find out how long the past turn's action should take. By default, an action will take 1 minute.

We'll start by emulating the behavior of "Uptempo": each turn we'll set the clock forward most of the way, then check to see what has changed since the last turn, print any relevant events, and only then set the clock forward the final minute. The exception is when an action is set to take no time at all; in that case, we'll skip the rest of the turn sequence rules entirely.

paste.png "Endurance"

Work duration is a number that varies.

Every turn:
    now work duration is 0;
    increment the turn count;
    follow the time allotment rules;
    if work duration is 0, rule succeeds;
    increase the time of day by (work duration minutes - 1 minute).

The time allotment rules are a rulebook.

A time allotment rule for examining or looking:
    now work duration is 0;
    rule succeeds.

A time allotment rule for going:
    now work duration is 2;
    rule succeeds.

A time allotment rule for going up:
    now work duration is 5;
    rule succeeds.

A time allotment rule for waiting:
    now work duration is 10;
    rule succeeds.

The last time allotment rule:
    now work duration is 1.

When play begins: now the right hand status line is "[time of day]".

The Quai is a room. "An attractive park at the edge of the river Aude: here you can wander among palm trees, and watch cyclists go by on the bike path; in the water there are ducks. In the cafe to your north, patrons sip their pastis; and above you is the medieval walled city and its castle."

The Cafe is north of the Quai. "A charming collection of umbrella-shaded tables, from which one can watch the river and the walls of the city beyond. The noise of traffic is only a minor distraction."

The City is above the Quai.

After going to the City:
    say "You struggle uphill for some distance...";
    continue the action.

At 9:15 AM:
    say "The bells ring out from Place Carnot."

Test me with "z / n / s / u".

***ExampleThe Hang of Thursdays
Turns take a quarter day each, and the game rotates through the days of the week.

***ExampleZqlran Era 8
Creating an alternative system of time for our game, using new units.