PXR_ScreenFade 脚本：官方SDK 脚本实现了屏幕的淡入淡出功能，封装了 CloseEyes 和 OpenEyes 方法，可以通过传入 Action 执行淡入淡出完成后的逻辑。

FadeController 脚本：

• 通过 GetComponent 获取 PXR_ScreenFade 组件，并调用 CloseEyes() 和 OpenEyes() 来控制屏幕的淡入淡出。
• 在淡入淡出结束后，通过传递的回调函数执行相关的操作  

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*******************************************************************************/using System;
using System.Collections;
using UnityEngine;namespace Unity.XR.PXR
{public class PXR_ScreenFade : MonoBehaviour{[Tooltip("Define the duration of screen fade.")]public float fadeTime = 5.0f;[Tooltip("Define the color of screen fade.")]public Color fadeColor = new Color(0.0f, 0.0f, 0.0f, 1.0f);public int renderQueue = 5000;private MeshRenderer fadeMeshRenderer;private MeshFilter fadeMeshFilter;private Material fadeMaterial = null;private bool isFading = false;private float currentAlpha;private float nowFadeAlpha;void Awake(){CreateFadeMesh();SetCurrentAlpha(0);}void OnEnable(){StartCoroutine(ScreenFade(1, 0));}void OnDestroy(){DestoryFadeMesh();}private void CreateFadeMesh(){fadeMaterial = new Material(Shader.Find("PXR_SDK/PXR_Fade"));fadeMeshFilter = gameObject.AddComponent<MeshFilter>();fadeMeshRenderer = gameObject.AddComponent<MeshRenderer>();var mesh = new Mesh();fadeMeshFilter.mesh = mesh;Vector3[] vertices = new Vector3[4];float width = 2f;float height = 2f;float depth = 1f;vertices[0] = new Vector3(-width, -height, depth);vertices[1] = new Vector3(width, -height, depth);vertices[2] = new Vector3(-width, height, depth);vertices[3] = new Vector3(width, height, depth);mesh.vertices = vertices;int[] tri = new int[6];tri[0] = 0;tri[1] = 2;tri[2] = 1;tri[3] = 2;tri[4] = 3;tri[5] = 1;mesh.triangles = tri;Vector3[] normals = new Vector3[4];normals[0] = -Vector3.forward;normals[1] = -Vector3.forward;normals[2] = -Vector3.forward;normals[3] = -Vector3.forward;mesh.normals = normals;Vector2[] uv = new Vector2[4];uv[0] = new Vector2(0, 0);uv[1] = new Vector2(1, 0);uv[2] = new Vector2(0, 1);uv[3] = new Vector2(1, 1);mesh.uv = uv;}private void DestoryFadeMesh(){if (fadeMeshRenderer != null)Destroy(fadeMeshRenderer);if (fadeMaterial != null)Destroy(fadeMaterial);if (fadeMeshFilter != null)Destroy(fadeMeshFilter);}public void SetCurrentAlpha(float alpha){currentAlpha = alpha;SetMaterialAlpha();}IEnumerator ScreenFade(float startAlpha, float endAlpha){float elapsedTime = 0.0f;while (elapsedTime < fadeTime){elapsedTime += Time.deltaTime;nowFadeAlpha = Mathf.Lerp(startAlpha, endAlpha, Mathf.Clamp01(elapsedTime / fadeTime));SetMaterialAlpha();yield return new WaitForEndOfFrame();}}private void SetMaterialAlpha(){Color color = fadeColor;color.a = Mathf.Max(currentAlpha, nowFadeAlpha);isFading = color.a > 0;if (fadeMaterial != null){fadeMaterial.color = color;fadeMaterial.renderQueue = renderQueue;fadeMeshRenderer.material = fadeMaterial;fadeMeshRenderer.enabled = isFading;}}public void CloseEyes(Action _action){StartCoroutine(ScreenFade(0, 1, _action));}IEnumerator ScreenFade(float startAlpha, float endAlpha, Action action){float elapsedTime = 0.0f;while (elapsedTime < fadeTime){elapsedTime += Time.deltaTime;nowFadeAlpha = Mathf.Lerp(startAlpha, endAlpha, Mathf.Clamp01(elapsedTime / fadeTime));SetMaterialAlpha();yield return new WaitForEndOfFrame();}action.Invoke();}public void OpenEyes(Action _action){StartCoroutine(ScreenFadeOpen(1, 0, _action));}IEnumerator ScreenFadeOpen(float startAlpha, float endAlpha, Action action){float elapsedTime = 0.0f;while (elapsedTime < fadeTime){elapsedTime += Time.deltaTime;nowFadeAlpha = Mathf.Lerp(startAlpha, endAlpha, Mathf.Clamp01(elapsedTime / fadeTime));SetMaterialAlpha();yield return new WaitForEndOfFrame();}action.Invoke();}IEnumerator ScreenFade(float closeTime, float openTime, Action action, Action complete){float elapsedTime = 0.0f;while (elapsedTime < closeTime){elapsedTime += Time.deltaTime;nowFadeAlpha = Mathf.Lerp(0, 1, Mathf.Clamp01(elapsedTime / closeTime));SetMaterialAlpha();yield return new WaitForEndOfFrame();}action.Invoke();float elapsedTime2 = 0.0f;while (elapsedTime2 < openTime){elapsedTime2 += Time.deltaTime;nowFadeAlpha = Mathf.Lerp(1, 0, Mathf.Clamp01(elapsedTime2 / openTime));SetMaterialAlpha();yield return new WaitForEndOfFrame();}complete?.Invoke();}public void Blink(float closeTime, float openTime, Action action, Action complete = null){StartCoroutine(ScreenFade(closeTime, openTime, action, complete));}}
}

using UnityEngine;
using Unity.XR.PXR;  // 引入PXR_ScreenFade的命名空间public class FadeController : MonoBehaviour
{private PXR_ScreenFade screenFade;void Start(){// 获取附加在同一对象上的PXR_ScreenFade组件，或者通过其他方式获取screenFade = GetComponent<PXR_ScreenFade>();// 触发淡出效果if (screenFade != null){// 画面淡入：从当前状态到完全黑屏（1为全黑）screenFade.CloseEyes(() => {Debug.Log("淡入结束，画面已完全黑屏");// 在淡入结束时执行一些操作});// 可以在一定时间后触发淡出效果，比如在5秒后淡出Invoke("OpenScreen", 5f);}}void OpenScreen(){// 画面淡出：从完全黑屏（1）回到正常视图（0）screenFade.OpenEyes(() => {Debug.Log("淡出结束，画面已恢复正常");// 在淡出结束时执行一些操作});}
}

官方文档链接：PICO Unity Integration SDK 画面淡入淡出