Files
2026-03-20 13:04:43 +02:00

69 lines
3.2 KiB
C#

using UnityEngine;
namespace FlappyBird.Gameplay.Bird
{
/// <summary>
/// Pure C# service — all bird physics and rotation logic lives here.
/// No MonoBehaviour, no Unity lifecycle. Injected via Zenject.
/// </summary>
public sealed class BirdController : IBirdController
{
// ── Dependencies ────────────────────────────────────────────────────
private readonly Rigidbody2D _rigidbody;
private readonly BirdSettings _settings;
/// <summary>
/// Constructor injection (Zenject will call this).
/// </summary>
/// <param name="rigidbody">The bird's Rigidbody2D component.</param>
/// <param name="settings">Configurable physics parameters.</param>
public BirdController(Rigidbody2D rigidbody, BirdSettings settings)
{
_rigidbody = rigidbody;
_settings = settings;
// Lock X position so the bird never drifts horizontally.
// The illusion of forward movement comes from pipes scrolling left.
_rigidbody.constraints = RigidbodyConstraints2D.FreezePositionX;
}
// ── IBirdController ─────────────────────────────────────────────────
/// <inheritdoc/>
public void Tick()
{
ApplyRotation();
}
/// <inheritdoc/>
public void Jump()
{
// Reset vertical velocity so each tap feels consistent regardless of fall speed.
// X is frozen via constraints, but we explicitly keep it zero for safety.
_rigidbody.linearVelocity = Vector2.zero;
_rigidbody.AddForce(Vector2.up * _settings.JumpForce, ForceMode2D.Impulse);
}
// ── Private helpers ─────────────────────────────────────────────────
/// <summary>
/// Maps vertical velocity to a tilt angle and smoothly rotates the bird.
/// Velocity range [rotationUpVelocity .. rotationDownVelocity] maps to
/// [maxUpRotation .. maxDownRotation] via an inverse-lerp → lerp.
/// </summary>
private void ApplyRotation()
{
float velocityY = _rigidbody.linearVelocity.y;
// Normalise velocity to [0, 1] (0 = falling fast, 1 = rising fast).
float t = Mathf.InverseLerp(
_settings.RotationDownVelocity,
_settings.RotationUpVelocity,
velocityY);
float targetAngle = Mathf.Lerp(
_settings.MaxDownRotation,
_settings.MaxUpRotation,
t);
// Read current Z rotation from the transform via the rigidbody.
float currentAngle = _rigidbody.rotation;
float smoothedAngle = Mathf.LerpAngle(
currentAngle,
targetAngle,
_settings.RotationSpeed * Time.deltaTime);
_rigidbody.MoveRotation(smoothedAngle);
}
}
}