Shader in C to material blueprint

anonymous_user_e281dc471 · April 6, 2014, 1:58pm

I’m currently moving my game from Unity to Unreal Engine 4.and I’m not familiar with this engine. I have shader written in C listed below. Anyone know how to move this to material brlueprint?

It script is called “Blending”. Maybe is similar function in material blueprints?

I would be very grateful if you’ll help me.

Thank you,

    Shader "Enviro/BumpedDiffuseOverlaySM3" {
    Properties {
        _Color ("Main Color", Color) = (1,1,1,1)
        _Opacity ("Color over opacity", Range (0, 1)) = 1
        _MainTex ("Color over (RGBA)", 2D) = "white" {}
        _BumpMap ("Normalmap over", 2D) = "bump" {}
        _MainTex2 ("Color under (RGBA)", 2D) = "white" {}
        _BumpMap2 ("Normalmap under", 2D) = "bump" {}
    }
     
    SubShader {
        Tags { "RenderType"="Opaque" }
        LOD 400
       
    CGPROGRAM
    #pragma surface surf Lambert
    #pragma target 3.0
     
    sampler2D _MainTex;
    sampler2D _BumpMap;
    sampler2D _MainTex2;
    sampler2D _BumpMap2;
    fixed4 _Color;
    float _Opacity;
     
    struct Input {
        float2 uv_MainTex;
        float2 uv_BumpMap;
        float2 uv_MainTex2;
        float2 uv_BumpMap2;
    };
     
    void surf (Input IN, inout SurfaceOutput o) {
        float4 tex = tex2D(_MainTex, IN.uv_MainTex);
        float4 tex2 = tex2D(_MainTex2, IN.uv_MainTex2);
        float4 dest;
        _Opacity*=tex.a;
        dest.rgb = tex2.rgb<=0.5 ? 2*tex.rgb*tex2.rgb : 1-2*(1-tex.rgb)*(1-tex2.rgb);
        dest.rgb = lerp(tex2.rgb, dest.rgb, _Opacity);
        dest.rgb *= _Color.rgb;
        o.Albedo = dest.rgb;
        o.Alpha = tex2.a * _Color.a;
       
        float4 norm = tex2D(_BumpMap, IN.uv_BumpMap);
        float4 norm2 = tex2D(_BumpMap2, IN.uv_BumpMap2);
        dest = norm2<=0.5 ? 2*norm*norm2 : 1-2*(1-norm)*(1-norm2);
        dest = lerp(norm2, dest, _Opacity);
        o.Normal = UnpackNormal(dest);
    }
    ENDCG
     
    }
     
    FallBack "Bumped Diffuse"
    }

Shadowriver · April 6, 2014, 2:44pm

You can find Custom block in Custom->Custom , let you create put custom shader code, there few problems thru:

Code language depends on renderer, DX
one will use HLSL, GL will use GLSL
and consoles might use something
else, so you would need to create
material for each, or else your game
will be exclusive to one
There no functions, you will need to
recrete it somehow in sperate block
if that even possible. In UDK (and
most likely in UE4 ) each block is a
function which you could call from
other custom blocks if you know the
name (UDK has code preview), but it
really hacky unreliable workaround.

You can also try to play in engine source code to implement your shader, but myself i don’t know here to start with that you will need to figure out yourself.

In general it is recommended to recrate function of your shader with pre-existing blocks.

xenlock · April 6, 2014, 3:00pm

After eyeballing the code, I think it should be possible to create this network simply using pre-existing nodes in the material editor. There’s no need to write any H/GLSL.

anonymous_user_e281dc471 · April 8, 2014, 9:08pm

I tried to recreate this shader in material blueprint and look what I’ve made. Have you any idea how to do this simply?

Shadowriver · April 8, 2014, 9:14pm