using UnityEngine;

public class CameraAdjuster : MonoBehaviour
{
    public Camera modelCamera;  // 3D模型的摄像机
    public Transform modelTransform; // 3D模型的 Transform
    public float padding = 1.2f; // 额外边距，防止模型太贴近边界

    void Start()
    {
        AdjustCameraToFitModel();
    }

    public void AdjustCameraToFitModel()
    {
        if (modelTransform == null || modelCamera == null) return;

        Renderer modelRenderer = modelTransform.GetComponentInChildren<Renderer>();
        if (modelRenderer == null) return;

        Bounds bounds = modelRenderer.bounds; // 获取模型的包围盒
        float modelSize = Mathf.Max(bounds.size.x, bounds.size.y, bounds.size.z); // 取最大的尺寸

        if (modelCamera.orthographic) // 正交投影
        {
            modelCamera.orthographicSize = (modelSize / 2) * padding;
        }
        else // 透视投影
        {
            float distance = modelSize / (2 * Mathf.Tan(modelCamera.fieldOfView * 0.5f * Mathf.Deg2Rad));
            modelCamera.transform.position = bounds.center - modelCamera.transform.forward * distance * padding;
        }

        modelCamera.transform.LookAt(bounds.center); // 让摄像机对准模型中心
    }
}