Feature Tour
The Feature Tour is a row of seven rooms. Each room has characters whose dialogue shows off part of the Yarn language: lines and options, jumps, detours, variables, enums, if statements, <<once>>, Commands, Functions, smart variables, line groups and node groups. A blue character called Capsley stands in every room and tells you what the room is about.
You walk the player character from room to room and talk to whoever you like. All the dialogue is in one Yarn Script, Tour.yarn, and every character starts a different node in it.
Running it
Open the FeatureTour scene in the Feature Tour sample’s folder and press Play.
| Control | What it does |
|---|---|
| W, A, S, D or the arrow keys | Walk. |
| Space | Talk to the character you’re standing next to. A speaking indicator appears on a character when you’re close enough. |
| Space, or the button in the dialogue box | Show the whole line, or move on to the next one. |
| A left click | Choose an option. |
The dialogue doesn’t start by itself. Walk up to Capsley in the first room and press Space to begin.
What’s in each room
| Room | Characters | What the dialogue shows | Yarn node |
|---|---|---|---|
| 1 | Capsley | An introduction to the tour | Capsley_Welcome |
| 2 | Bob | Nodes and lines | Room2_Nodes_and_Lines |
| 2 | Bill | Options, and <<jump>> to another node | Room2_Options_and_Jumps_1 |
| 3 | Bruce | <<detour>> to another node and back | Room3_Detours_1 |
| 4 | Ogbert | A variable used as the character’s name, set by an option | Room4_Variables_1 |
| 4 | Sally | Number and boolean variables | Room4_Variables_2 |
| 5 | Mary | <<if>> and <<else>> | Room5_IfStatements_1 |
| 5 | Thor | An option with a condition | Room5_ConditionalOptions_1 |
| 5 | Ruby | An enum | Room5_Enums_1 |
| 5 | Norb | <<once>> | Room5_Once_1 |
| 6 | Derek | The built-in <<wait>> Command | Room6_Commands_1 |
| 6 | Beryl | The built-in dice() and random_range() Functions | Room6_Functions_1 |
| 6 | Reginald | A smart variable | Room6_SmartVariables_1 |
| 7 | Sven | A line group | Room7_LineGroups_1 |
| 7 | Dr Node | A node group | Room7_NodeGroups_1 |
Capsley’s node in each room is Capsley_Room2 to Capsley_Room7. For how each feature is written, see Writing Yarn Scripts.
Some characters react to what you did elsewhere. Mary and Thor say different things once you’ve talked to Sally, and Dr Node’s dialogue depends on the meal you chose with Ruby and on how much gold you have left after Reginald.
How it works
The scene
There’s one Dialogue Runner for the whole building, on the Dialogue System prefab. Its Yarn Project is CharacterSample.yarnproject, which includes Tour.yarn, and its Presenters are the Dialogue System’s Line Presenter, Options Presenter and Line Advancer. See The Dialogue Runner.
Each character has a Dialogue Interactable, from the shared sample scripts. Its Dialogue setting is the Yarn Project and the node to start, picked from a dropdown, and its Dialogue Runner is the scene’s one Dialogue Runner. When you press Space next to a character, it calls StartDialogue() with that node name, and waits for the dialogue to finish. A character can’t be talked to while another conversation is running. If the node name is a node group, the speaking indicator only appears if something in the group can run. Character Appearance gives each character its own colours.
To find out which node a character runs, select the character in the Hierarchy and look at its Dialogue Interactable. Then find that node in Tour.yarn.
Watching the variables
The Dialogue System’s In Memory Variable Storage has its Debug Text View set to the Variables text on the Canvas. Every frame, the Variable Storage writes the name, value and type of each variable it’s storing into that text. A variable shows up there once it has been set. As you talk to Sally, Ruby and Reginald, you can watch $player_spoke_to_sally, $player_meal and $player_gold change.
Declaring the variables
All the variables in the tour are declared at the top of Capsley’s first node. Declarations aren’t run like other statements. They apply to the whole Yarn Project, so every node can use these variables, even if you never talk to Capsley.
<<declare $NPC_Variables_Name = "Ogbert">>
<<declare $player_gold = 10>>
<<declare $player_spoke_to_sally = false>>
<<enum Meal>>
<<case None>>
<<case Ramen>>
<<case Pizza>>
<<case MeatProduct>>
<<case Sludge>>
<<endenum>>
<<declare $player_meal = Meal.None>>
<<declare $player_can_afford_bribe = $player_gold >= 6>>true when you talk to Sally. Mary and Thor check it.None. Dr Node checks it.true while you have at least 6 gold. See Smart Variables.The smart variable
Reginald checks $player_can_afford_bribe. Nothing in the script sets it. Its value is worked out from $player_gold each time it’s read.
<<if $player_can_afford_bribe>>
Reginald: Anyway.
Reginald: I know you can afford to bribe me because you have enough gold.
<<set $player_gold = $player_gold - 6>>You start with 10 gold, so the first time you talk to Reginald you can afford it, and he takes 6. That leaves 4, so $player_can_afford_bribe is now false. The next time, he says you can’t afford to bribe him.
Dr Node’s node group
Dr Node starts Room7_NodeGroups_1, which is a node group of five nodes with the same title. Each has when: headers that say when it can run. When the dialogue starts there, the Dialogue Runner picks one of the nodes that can run.
when: headers | What Dr Node talks about |
|---|---|
when: once and when: !visited("Room7_NodeGroups_1") | How node groups work. Only shown once. |
when: !$player_can_afford_bribe | You can’t afford a bribe. |
when: $player_meal == .None | You haven’t got a meal. |
when: $player_meal == .Ramen | You have ramen. |
when: always | This node is a fallback. |
The first time you talk to him, the node with once runs. Its two when: headers make it more specific than the nodes with one, so it wins even when another node, like the .None one, could run. After that, what he says depends on what you’ve done in rooms 5 and 6. The when: always node means there’s always something that can run, so you can talk to him as many times as you like. See Saliency and Storylets for how the Dialogue Runner picks.
Things to try
- In
Tour.yarn, change<<declare $player_gold = 10>>to<<declare $player_gold = 4>>. Sally tells you that you have 4 gold, Reginald says you can’t afford to bribe him, and after Dr Node’s first conversation, hiswhen: !$player_can_afford_bribenode can be picked. - Add a fourth line to Sven’s line group in
Room7_LineGroups_1, starting with=> Sven:. Talk to him a few times to see each greeting. - Select a character, and change the node in its Dialogue Interactable to another one from the list, such as
Room6_Functions_1. That character now says Beryl’s lines.