[PostEffect]FadeIn/FadeOutのImageEffect

環境

• Unity5.5
• DOTween

コード

test.cs

using System.Collections;
using System.Collections.Generic;
using UnityEngine;

using DG.Tweening;

[RequireComponent(typeof(Camera)),ExecuteInEditMode]
public class FadeEffect : MonoBehaviour {

    private Material material;

    private bool isFade;
    private float _black;

    [SerializeField]
    private float fadeDuration;

    void Awake()
    {
        material = new Material (Shader.Find ("Custom/Fade"));
    }

    void Start()
    {

        StartCoroutine (gameLogic());

    }

    IEnumerator gameLogic()
    {

        yield return FadeOut ();

        Debug.Log ("Done FadeOut");

        yield return FadeIn ();

        Debug.Log ("Done FadeIn");

    }

    public IEnumerator FadeOut()
    {
        isFade = true;

        DOTween.To (black => _black = black, 1.0f, 0.0f, fadeDuration)
            .OnComplete (() => {
                isFade = false;
        });

        yield return new WaitWhile (() => isFade == true);

    }

    public IEnumerator FadeIn()
    {
        isFade = true;

        DOTween.To (black => _black = black, 0.0f, 1.0f, fadeDuration)
            .OnComplete (() => {
                isFade = false;
            });

        yield return new WaitWhile (() => isFade == true);
    }

    void OnRenderImage(RenderTexture source, RenderTexture destination)
    {
        if (isFade) {
            UpdateMaterial ();
            Graphics.Blit (source, destination, material);
        }
    }

    void UpdateMaterial()
    {
        material.SetFloat ("_Black", _black);
    }
}

Fade.shader

Shader "Custom/Fade"
{
    Properties
    {
        _MainTex ("Texture", 2D) = "white" {}
        _Black ("black", float) = 0.0 
    }
    SubShader
    {
        // No culling or depth
        Cull Off ZWrite Off ZTest Always

        Pass
        {
            CGPROGRAM
            #pragma vertex vert
            #pragma fragment frag

            #include "UnityCG.cginc"

            struct appdata
            {
                float4 vertex : POSITION;
                float2 uv : TEXCOORD0;
            };

            struct v2f
            {
                float2 uv : TEXCOORD0;
                float4 vertex : SV_POSITION;
            };

            v2f vert (appdata v)
            {
                v2f o;
                o.vertex = mul(UNITY_MATRIX_MVP, v.vertex);
                o.uv = v.uv;
                return o;
            }

            sampler2D _MainTex;
            float _Black;

            fixed4 frag (v2f i) : SV_Target
            {
                fixed4 col = tex2D(_MainTex, i.uv);
                col = col * _Black;
                return col;
            }
            ENDCG
        }
    }
}

説明

Scriptからmaterialの_BlackをDOTweenで指定時間で1.0/0.0になるように更新。
fragmentシェーダー側でPropertyの_Blackを全ピクセルに加算。

使い方としてはFadeOutの後に何か処理をしてからFadeIn命令を出す感じです。