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Chapter 8: Vehicles, Animals and Furniture
§8.1. Bicycles, Cars and Boats; §8.2. Ships, Trains and Elevators; §8.3. Animals; §8.4. Furniture; §8.5. Kitchen and Bathroom
|Contents of The Inform Recipe Book|
|Chapter 7: Other Characters|
|Chapter 9: Props: Food, Clothing, Money, Toys, Books, Electronics|
|Indexes of the examples|
§8.1. Bicycles, Cars and Boats
The vehicle kind in Inform refers to an object which can carry at least one person, but is small enough to fit into a single location:
In the Garden is a vehicle called the motor mower.
We can then apply different rules to a player going somewhere on foot or in the vehicle. Peugeot (a bicycle) is an easy example; No Relation (a car) adds an ignition switch to the vehicle; Straw Boater (a motorboat) gets around areas of lake where travel on foot is not just slower but impossible.
Hover (a sci-fi "hover-bubble") changes the appearance of the landscape when it is seen from inside the vehicle.
See Ships, Trains and Elevators for larger conveyances
|Start of Chapter 8: Vehicles, Animals and Furniture|
|Back to Chapter 7: Other Characters: §7.16. Social Groups|
|Onward to §8.2. Ships, Trains and Elevators|
Let's say that our protagonist is about to flee . Obviously, he can't make the journey on foot; he needs transportation.
We make the ten-speed bike a rideable vehicle because we want to say that the player is on it rather than in it. Then our other room:
And now we borrow from the Actions chapter to prevent travel without the proper equipment:
We need to designate certain rooms as roads. Since the status of being a road will not change during play, we do this with a kind:
The car is a vehicle in Trafalgar Square. The ignition is a device. The ignition is part of the car. Instead of going by the car when the ignition is switched off: say "The ignition is off at the moment." Instead of switching on the car, try switching on the ignition. Instead of switching off the car, try switching off the ignition.
(In the course of the writing of Inform 7, much of Trafalgar Square was pedestrianised, making this example already out of date.)
A further technical note: notice "going by a vehicle" in the above rule, rather than "going by something". A rule such as "Instead of going by something..." will be matched whenever the player tries to go some direction while in an enterable object, whether or not that object is actually capable of movement. This is sometimes useful, but in this case we want the warning to apply only when the player is in a vehicle; if we added Trafalgar Square's statue bases to the scenario, we would not want
So we restrict the rule to "Instead of going by a vehicle..."
Sometimes we like to give properties to kinds of thing, but not fill them in in all cases. For instance, we might have vehicles that optionally make noise, and those might have a "movement sound".
All properties have a default value, which we can find by looking in the Kinds tab of the index. This is what the property will be set to automatically, if we do not change it ourselves. In the case of a text property, that is ""; so for instance we might use our movement sound thus:
North of the Boathouse is the Shallow Water. The description of Shallow Water is "Just south is the boathouse, and beyond it are trees and the marble terrace of the house above. The water deepens to the north."
North of Shallow Water is Deep Water. The description of Deep Water is "From here the boathouse has dwindled invisibly to the south, and you have a broad panorama of the shoreline, all the way down to the Skeleton Point Lighthouse in the southeast."
A vehicle has some text called the movement sound. The sailboat and the motorboat are vehicles in the Boathouse. The movement sound of the motorboat is "VRRRROOOMMMM..." Understand "boat" as the sailboat. Understand "boat" as the motorboat.
Note that we haven't given the sailboat any movement sound at all.
Suppose we want the player to see a modified room description when he's viewing the place from inside a vehicle. There are several conceivable ways of doing this; the example here shows a rather advanced way, but is very flexible and will let us write all sorts of special cases.
Emerald City is a room. "All the buildings are spires and none of them have doors." The Vast Desert is west of Emerald City. "[if the player is in a vehicle]Outside, a[otherwise]A[end if] trackless waste stretches as far as the eye can see in every direction."
The hover-bubble is a vehicle in the Emerald City. "Your hover-bubble awaits." The description is "The hover-bubble is a clear globe-shaped vehicle capable of transporting you anywhere you could walk, but faster." Understand "bubble" as the hover-bubble. The hover-bubble contains a chocolate wrapper and a parking ticket.
Here's the tricky part, which relies on material from the chapters on Activities and Rulebooks:
Now we've done that, we can write a "rule for describing the interior" of something, which will print whatever we like:
In fact, as a special refinement, we could even say:
Rule for describing the interior of the hover-bubble when the hover-bubble contains more than one thing:
say "The hover-bubble is transparent, but tints everything outside very faintly lavender. Beside you you can see [a list of other things in the hover-bubble]."
And now anything that's beside us in the vehicle will be described during that first paragraph, rather than later on.