f1uctus / crown

👑 ⌚ An ambitious Java game framework with time-travelling support.

👑 Crown 👑

A Java framework for RPG/roguelikes.

API Structure

Package	Description
com.crown.creatures	Basic Creature API
com.crown.i18n	Internationalization helpers
com.crown.maps	3D / 2D(tiled) maps logic
— ...maps.pathfinding	3D map pathfinding algorithms and heuristics
com.crown.skills	Creature skills API
com.crown.time	VirtualClock implementation + Timeline (time-travelling API - may be unstable in some cases)
com.crown.tools	Random class extensions & other utility stuff

Usage

Maven dependency (GitHub Packages)

<dependency>
    <groupId>com.github.F1uctus</groupId>
    <artifactId>crown</artifactId>
    <version></version>
</dependency>

To see the most comprehensive usage overview, see my demo game, or RPGram game implementations.

Code

Every game must initialize these base structures at the program beginning:

VirtualClock

VirtualClock is an abstraction over a fixed-delay timer, to allow your game to perform periodical actions.
In general an instance is created that way:

var gameClock = new VirtualClock(
    10, // period between game ticks, in milliseconds
    gameWindow::repaint // a function to execute on every tick
);

Then, clock is started using startAt(Instant) or startAtRnd().

GameState

GameState should be implemented in your code by inheritance from BaseGameState. That object contains global game map, and a players collection.

Initialization example:

var gameState = new GameState(new GlobalMap(
    "Map name",
    500,            // x size
    500,            // y size
    MapLevel.height // z size
))

Main timeline

Timeline is a main storage of actions performed by every creature in the game. It is a 'heart' of time-travelling logic.

Initialization is static:

Timeline.init(gameClock, gameState);

Internationalization

Most of Crown's action methods return ITemplate object - a localizable message storage, so you must add at least one resource bundle to store built-in message properties. They include:

Property name	Description
message.ok	Action successful.
delta.outOfBounds	Some property (e.g. hp) went out of range while executing action.
time.travel.future	Attempt to time-travel to the future.
time.travel.notFromMain	Attempt to time-travel being in the past.
time.travel.parallel	Attempt to time-travel by 2 separate players (not supported yet).
commit.fromMain	Attempt to save time-travel changes being in the main timeine.
rollback.fromMain	Attempt to undo time-travel changes being in the main timeine.
move.lowEnergy	Obvious.
move.obstacle	Obvious.

To easily interact with your resource bundles there is an I18n class with static methods to wrap your messages to the localizable ITemplates. To translate ITemplate to some language, a ITemplate.getLocalized(String lang) method is used. Of course, you can add your own localizable messages and use them the same way. For example:

var result = I18n.of("mage.unknownSpell");
result.getLocalized("en") // => I don't know that spell.

To initialize I18n class this approach is used:

var bundles = new HashMap<String, ResourceBundle>();
// "gameMessages" is a name for your resource bundle file, without a locale.
bundles.put("ru", ResourceBundle.getBundle("gameMessages", new Locale("ru_RU")));
bundles.put("en", ResourceBundle.getBundle("gameMessages", new Locale("en_US")));
// more bundles...
I18n.init(bundles);

Time-travelling API implementation overview

I tried to keep diagram as simple as possible, but feel free to report any inconvenience.