MarmosetInput.cginc：
Input结构定义：
struct Input
{
#if defined(MARMO_PACKED_UV) || defined(MARMO_PACKED_VERTEX_OCCLUSION) || defined(MARMO_PACKED_VERTEX_COLOR)
float4 texcoord;
#else
float2 texcoord;
#endif
float3 worldNormal;
#if defined(MARMO_SPECULAR_DIRECT) || defined(MARMO_SPECULAR_IBL)
float3 viewDir;
#endif
#if defined(MARMO_COMPUTE_WORLD_POS)
#ifdef MARMO_U5_WORLD_POS
float3 worldPos; //this is free in Unity 5
#endif
#else
float4 worldP; //lets write our own
#endif
#if defined(MARMO_VERTEX_COLOR) || defined(MARMO_VERTEX_LAYER_MASK)
half4 color : COLOR;
#elif defined(MARMO_VERTEX_OCCLUSION)
half2 color : COLOR;
#endif
#ifdef MARMO_DIFFUSE_VERTEX_IBL
float3 vertexIBL;
#endif
INTERNAL_DATA
};
Output结构定义：
struct MarmosetOutput
{
half3 Albedo; //diffuse map RGB
half Alpha; //diffuse map A
half3 Normal; //world-space normal
half3 Emission; //contains IBL contribution
half Specular; //specular exponent (required by Unity)
#ifdef MARMO_SPECULAR_DIRECT
half3 SpecularRGB; //specular mask
#endif
};
Unity自带的Output结构定义：
struct SurfaceOutput
{
fixed3 Albedo;
fixed3 Normal;
fixed3 Emission;
half Specular;
fixed Gloss;
fixed Alpha;
};
// Metallic workflow
struct SurfaceOutputStandard
{
fixed3 Albedo; // base (diffuse or specular) color
fixed3 Normal; // tangent space normal, if written
half3 Emission;
half Metallic; // 0=non-metal, 1=metal
// Smoothness is the user facing name, it should be perceptual smoothness but user should not have to deal with it.
// Everywhere in the code you meet smoothness it is perceptual smoothness
half Smoothness; // 0=rough, 1=smooth
half Occlusion; // occlusion (default 1)
fixed Alpha; // alpha for transparencies
};
// Specular workflow
struct SurfaceOutputStandardSpecular
{
fixed3 Albedo; // diffuse color
fixed3 Specular; // specular color
fixed3 Normal; // tangent space normal, if written
half3 Emission;
half Smoothness; // 0=rough, 1=smooth
half Occlusion; // occlusion (default 1)
fixed Alpha; // alpha for transparencies
};
MarmosetDirect.cginc：
直接光照的主要代码，去掉deferred lighting相关的代码。
#ifndef MARMOSET_DIRECT_CGINC
#define MARMOSET_DIRECT_CGINC
// Core
inline float3 wrapLighting(float DP, float3 scatter)
{
scatter *= 0.5;
float3 integral = float3(1.0,1.0,1.0)-scatter;
float3 light = saturate(DP * integral + scatter);
float shadow = (DP*0.5+0.5);
shadow *= shadow;
return light * integral * shadow;
}
// NOTE: some intricacy in shader compiler on some GLES2.0 platforms (iOS) needs 'viewDir' & 'h'
// to be mediump instead of lowp, otherwise specular highlight becomes too bright.
inline half4 marmosetLighting (MarmosetOutput s, half3 viewDir, half3 lightDir, half3 lightColor)
{
half4 frag = half4(0.0,0.0,0.0,s.Alpha);
#if defined(MARMO_DIFFUSE_DIRECT) || defined(MARMO_SPECULAR_DIRECT)
half3 L = lightDir;
half3 N = s.Normal;
#ifdef MARMO_HQ
L = normalize(L);
#endif
#endif
#ifdef MARMO_DIFFUSE_DIRECT
half dp = saturate(dot(N,L));
#ifdef MARMO_DIFFUSE_SCATTER
float4 scatter = _Scatter * _ScatterColor;
half3 diff = wrapLighting(dp, scatter.rgb);
diff *= 2.0 * s.Albedo.rgb; //*2.0 to match Unity
#else
half3 diff = (2.0 * dp) * s.Albedo.rgb; //*2.0 to match Unity
#endif
frag.rgb = diff * lightColor;
#endif
#ifdef MARMO_SPECULAR_DIRECT
half3 H = normalize(viewDir+L);
float specRefl = saturate(dot(N,H));
half3 spec = pow(specRefl, s.Specular*512.0);
#ifdef MARMO_HQ
//self-shadowing blinn
#ifdef MARMO_DIFFUSE_DIRECT
spec *= saturate(10.0*dp);
#else
spec *= saturate(10.0*dot(N,L));
#endif
#endif
spec *= lightColor;
frag.rgb += (0.5 * spec) * s.SpecularRGB; //*0.5 to match Unity
#endif
return frag;
}
//forward lighting
inline half4 LightingMarmosetDirect( MarmosetOutput s, half3 lightDir, half3 viewDir, half atten )
{
return marmosetLighting( s, viewDir, lightDir, _LightColor0 * atten);
}
inline half4 LightingMarmosetDirect( MarmosetOutput s, half3 viewDir, UnityGI gi )
{
fixed4 c;
c = marmosetLighting (s, viewDir, gi.light.dir, gi.light.color);
#ifdef UNITY_LIGHT_FUNCTION_APPLY_INDIRECT
c.rgb += s.Albedo * gi.indirect.diffuse;
#endif
return c;
}
inline void LightingMarmosetDirect_GI (MarmosetOutput s, UnityGIInput giInput, inout UnityGI gi)
{
gi = UnityGlobalIllumination(giInput, 1.0, s.Normal);
}
#endif
MarmosetSurf.cginc：
旧版本的surf代码：
#ifndef MARMOSET_SURF_CGINC
#define MARMOSET_SURF_CGINC
void MarmosetSurf(Input IN, inout MarmosetOutput OUT)
{
#define uv_diff IN.uv_MainTex
#define uv_spec IN.uv_MainTex
#define uv_bump IN.uv_MainTex
#define uv_glow IN.uv_MainTex
//DIFFUSE
#if defined(MARMO_DIFFUSE_DIRECT) || defined(MARMO_DIFFUSE_IBL)
half4 diff = tex2D( _MainTex, uv_diff );
diff *= _Color;
//camera exposure is built into OUT.Albedo
diff.rgb *= _ExposureIBL.w;
OUT.Albedo = diff.rgb;
OUT.Alpha = diff.a;
#ifdef MARMO_PREMULT_ALPHA
OUT.Albedo *= diff.a;
#endif
#else
OUT.Albedo = half3(0.0,0.0,0.0);
OUT.Alpha = 1.0;
#endif
//NORMALS
#ifdef MARMO_NORMALMAP
float3 N = UnpackNormal(tex2D(_BumpMap,uv_bump));
#ifdef MARMO_HQ
N = normalize(N);
#endif
OUT.Normal = N; //N is in tangent-space
#else
//OUT.Normal is not modified when not normalmapping
float3 N = OUT.Normal; //N is in world-space
#ifdef MARMO_HQ
N = normalize(N);
#endif
#endif
//SPECULAR
#if defined(MARMO_SPECULAR_DIRECT) || defined(MARMO_SPECULAR_IBL)
half4 spec = tex2D(_SpecTex, uv_spec);
float3 E = IN.viewDir; //E is in whatever space N is
#ifdef MARMO_HQ
E = normalize(E);
half fresnel = splineFresnel(N, E, _SpecInt, _Fresnel);
#else
half fresnel = fastFresnel(N, E, _SpecInt, _Fresnel);
#endif
//camera exposure is built into OUT.Specular
spec.rgb *= _SpecColor.rgb * fresnel * _ExposureIBL.w;
OUT.Specular = spec.rgb;
half glossLod = glossLOD(spec.a, _Shininess);
OUT.Gloss = glossExponent(glossLod);
//conserve energy by dividing out specular integral
OUT.Specular *= specEnergyScalar(OUT.Gloss);
#endif
//SPECULAR IBL
#ifdef MARMO_SPECULAR_IBL
#ifdef MARMO_NORMALMAP
float3 R = WorldReflectionVector(IN, OUT.Normal);
#else
float3 R = IN.worldRefl;
#endif
#ifdef MARMO_SKY_ROTATION
R = mulVec3(_SkyMatrix,R); //per-fragment matrix multiply, expensive
#endif
#ifdef MARMO_MIP_GLOSS
half3 specIBL = glossCubeLookup(_SpecCubeIBL, R, glossLod);
#else
half3 specIBL = specCubeLookup(_SpecCubeIBL, R)*spec.a;
#endif
OUT.Emission += specIBL.rgb * spec.rgb * _ExposureIBL.y;
#endif
//DIFFUSE IBL
#ifdef MARMO_DIFFUSE_IBL
N = WorldNormalVector(IN,N); //N is in world-space
#ifdef MARMO_SKY_ROTATION
N = mulVec3(_SkyMatrix,N); //per-fragment matrix multiply, expensive
#endif
half3 diffIBL = diffCubeLookup(_DiffCubeIBL, N);
OUT.Emission += diffIBL * diff.rgb * _ExposureIBL.x;
#endif
//GLOW
#ifdef MARMO_GLOW
half4 glow = tex2D(_Illum, uv_glow);
glow.rgb *= _GlowColor.rgb;
glow.rgb *= _GlowStrength;
glow.a *= _EmissionLM;
glow.rgb += OUT.Albedo * glow.a;
OUT.Emission += glow.rgb * _ExposureIBL.w;
#endif
}
#endif
IBL实现的两个关键函数：
half3 diffCubeLookup(samplerCUBE diffCube, float3 worldNormal)
{
half4 diff = texCUBE(diffCube, worldNormal);
return fromRGBM(diff);
}
half3 specCubeLookup(samplerCUBE specCube, float3 worldRefl)
{
half4 spec = texCUBE(specCube, worldRefl);
return fromRGBM(spec);
}
IBL.diffuse使用world normal查询，IBL.specular使用world reflection查询。
宏定义解析：
MARMO_DIFFUSE_SPECULAR_COMBINED
Diffuse/Specular合并
_MainTex.RGBA = RGB表示Diffuse，A表示Specular强度和Gloss
MARMO_PACKED_UV
UV打包
#ifdef MARMO_PACKED_UV
o.texcoord.zw = v.texcoord1.xy;
#endif
MARMO_PACKED_VERTEX_COLOR
顶点色打包
#ifdef MARMO_PACKED_VERTEX_COLOR
o.texcoord.zw = v.color.rg;
o.worldP.w = v.color.b;
#endif