unity3D制作skybox淡入淡出

首先建立个shader

Shader "Custom/Skybox" {

Properties {
    _Tint ("Tint Color", Color) = (.5, .5, .5, .5)
    _FrontTex ("Front (+Z)", 2D) = "white" {}
    _BackTex ("Back (-Z)", 2D) = "white" {}
    _LeftTex ("Left (+X)", 2D) = "white" {}
    _RightTex ("Right (-X)", 2D) = "white" {}
    _UpTex ("Up (+Y)", 2D) = "white" {}
    _DownTex ("Down (-Y)", 2D) = "white" {}
    _FrontTex2("2 Front (+Z)", 2D) = "white" {}
    _BackTex2("2 Back (-Z)", 2D) = "white" {}
    _LeftTex2("2 Left (+X)", 2D) = "white" {}
    _RightTex2("2 Right (-X)", 2D) = "white" {}
    _UpTex2("2 Up (+Y)", 2D) = "white" {}
    _DownTex2("2 Down (-Y)", 2D) = "white" {}
    _Color ("Fade (use alpha)", Color) = (1,1,1,1)
}

SubShader {
    Tags { "Queue" = "Background" }
    Cull Off
    ZWrite On
    ZTest Always
    Fog { Mode Off }
    Lighting Off       
    Color [_Tint]
    Pass {
        SetTexture [_FrontTex] { combine texture }
        SetTexture[_FrontTex2] { 
            constantColor [_Color]
            combine texture lerp (constant) previous
        }
    }
    Pass {
        SetTexture [_BackTex] { combine texture }
        SetTexture[_BackTex2] { 
            constantColor [_Color]
            combine texture lerp (constant) previous
        }
    }
    Pass {
        SetTexture [_LeftTex] { combine texture }
        SetTexture[_LeftTex2] { 
            constantColor [_Color]
            combine texture lerp (constant) previous
        }
    }
    Pass {
        SetTexture [_RightTex] { combine texture }
        SetTexture[_RightTex2] { 
            constantColor [_Color]
            combine texture lerp (constant) previous
        }
    }
    Pass {
        SetTexture [_UpTex] { combine texture }
        SetTexture[_UpTex2] { 
            constantColor [_Color]
            combine texture lerp (constant) previous
        }
    }
    Pass {
        SetTexture [_DownTex] { combine texture }
        SetTexture[_DownTex2] { 
            constantColor [_Color]
            combine texture lerp (constant) previous
        }
    }
}

Fallback "RenderFX/Skybox", 1
}

材质间的动画转换

private var thisMaterial : Material;
private var fadeSpeed : float = 0.4;

function Start (){
    thisMaterial = RenderSettings.skybox;
    thisMaterial.color.a = 0.0;
}

function Update () {
    thisMaterial.color.a += (fadeSpeed * Time.deltaTime); 
    thisMaterial.color.a = Mathf.Clamp(thisMaterial.color.a, 0.0, 1.0);
}

skybox的纹理褪色，渐渐的转变。

public var blackTexture : Texture2D;

function Start (){
    thisMaterial = RenderSettings.skybox;
    thisMaterial.color.a = 0.0;

    thisMaterial.SetTexture("_FrontTex", blackTexture);
    thisMaterial.SetTexture("_BackTex", blackTexture);
    thisMaterial.SetTexture("_LeftTex", blackTexture);
    thisMaterial.SetTexture("_RightTex", blackTexture);
    thisMaterial.SetTexture("_UpTex", blackTexture);
    thisMaterial.SetTexture("_DownTex", blackTexture);
}
function Update () {
    thisMaterial.color.a += (fadeSpeed * Time.deltaTime); 
    thisMaterial.color.a = Mathf.Clamp(thisMaterial.color.a, 0.0, 1.0);
}

设置纹理等

thisMaterial.SetTexture("_FrontTex2", textureVariable);