Character Controller

Using the built-in character controller which handles collision detection. Great for any movement style.

// This is an example of how to implement a platformer controller using the KinematicCharacterController

import {
  Behavior,
  EntityDestroyed,
  Collider,
  Vector2,
  syncedValue,
} from "@dreamlab/engine";
import { KinematicCharacterController } from "@dreamlab/vendor/rapier.ts";

export default class PlatformMovement extends Behavior {
  #collider: Collider = this.entity.cast(Collider);
  #controller: KinematicCharacterController | undefined;

  @syncedValue()
  speed = 10.0;

  @syncedValue()
  jumpForce = 20.0;

  @syncedValue()
  jumpAcceleration = 40;

  @syncedValue()
  gravity = 90.0;

  @syncedValue()
  maxJumpTime = 1; // Maximum duration the jump key affects the jump

  #verticalVelocity = 0;
  #isGrounded = false;
  #jumpTimeCounter = 0;

  #up = this.inputs.create("@movement/up", "Move Up", "KeyW");
  #down = this.inputs.create("@movement/down", "Move Down", "KeyS");
  #left = this.inputs.create("@movement/left", "Move Left", "KeyA");
  #right = this.inputs.create("@movement/right", "Move Right", "KeyD");
  #jump = this.inputs.create("@movement/jump", "Jump", "Space");

  onInitialize(): void {
    if (this.game.isClient()) {
      this.#controller =
        this.game.physics.world.createCharacterController(0.01);
    }

    this.listen(this.entity, EntityDestroyed, () => {
      if (this.#controller)
        this.game.physics.world.removeCharacterController(this.#controller);
    });
  }

  onTick(): void {
    if (!this.#controller) return;

    const deltaTime = this.game.time.delta / 1000; // Convert to seconds

    let horizontalInput = 0;
    if (this.#right.held) horizontalInput += 1;
    if (this.#left.held) horizontalInput -= 1;

    const horizontalVelocity = horizontalInput * this.speed;

    // Jumping logic
    if (this.#jump.pressed && this.#isGrounded) {
      this.#verticalVelocity = this.jumpForce;
      this.#jumpTimeCounter = 0;
    }

    if (this.#jump.held && this.#jumpTimeCounter < this.maxJumpTime) {
      // Apply upward acceleration while the jump key is held
      this.#verticalVelocity += this.jumpAcceleration * deltaTime;
      this.#jumpTimeCounter += deltaTime;
    }

    // Create movement vector
    const movement = new Vector2(
      horizontalVelocity * deltaTime,
      this.#verticalVelocity * deltaTime
    );

    this.#controller.computeColliderMovement(this.#collider.collider, movement);
    const corrected = this.#controller.computedMovement();

    this.#isGrounded = this.#controller.computedGrounded();
    if (!this.#isGrounded) this.#verticalVelocity -= this.gravity * deltaTime;

    this.entity.pos = this.entity.pos.add(corrected);
  }
}