虚幻4 改变默认UI Disable的Shader

虚幻默认的UI Disable 太难看，

文件：

Engine_Updating\Engine\Shaders\SlateElementPixelShader.usf

#if DRAW_DISABLED_EFFECT
//desaturate
float3 LumCoeffs = float3( 0.3, 0.59, .11 );
float Lum = dot( LumCoeffs, OutColor.rgb );
OutColor.rgb = lerp( OutColor.rgb, float3(Lum,Lum,Lum), .8 );

float3 Grayish = {.1, .1, .1};

OutColor.rgb = lerp( OutColor.rgb, 3, clamp( distance( OutColor.rgb, Grayish ), 0, .8)  );
#endif

改为：

<span style="font-family: Arial, Helvetica, sans-serif;">#if DRAW_DISABLED_EFFECT</span>

//desaturate
float3 LumCoeffs = float3( 0.3, 0.59, .11 );
float Lum = dot( LumCoeffs, OutColor.rgb );
OutColor.rgb = lerp( OutColor.rgb, float3(Lum,Lum,Lum), .8 );

//float3 Grayish = {.1, .1, .1};

//OutColor.rgb = lerp( OutColor.rgb, 3, clamp( distance( OutColor.rgb, Grayish ), 0, .8)  );
#endif

可以用虚幻的材质编辑器测试一下，

再次开启编辑器会导致编辑器卡在95%，因为在编译新的shader。等一会就好了。