{"id":940,"date":"2022-08-10T17:08:31","date_gmt":"2022-08-10T09:08:31","guid":{"rendered":"https:\/\/www.acgloby.com\/?p=940"},"modified":"2022-08-10T17:08:31","modified_gmt":"2022-08-10T09:08:31","slug":"pbr-brdf%e6%a8%a1%e5%9e%8b","status":"publish","type":"post","link":"https:\/\/www.acgloby.com\/index.php\/2022\/08\/10\/pbr-brdf%e6%a8%a1%e5%9e%8b\/","title":{"rendered":"PBR"},"content":{"rendered":"\n<h3 class=\"wp-block-heading\">PBR\u7406\u8bba<\/h3>\n\n\n\n<p class=\"wp-block-paragraph\"><a href=\"https:\/\/zhuanlan.zhihu.com\/p\/53086060\" data-type=\"URL\" data-id=\"https:\/\/zhuanlan.zhihu.com\/p\/53086060\" target=\"_blank\"  rel=\"nofollow\" >\u3010\u57fa\u4e8e\u7269\u7406\u7684\u6e32\u67d3\uff08PBR\uff09\u767d\u76ae\u4e66\u3011\uff08\u4e00\uff09 \u5f00\u7bc7\uff1aPBR\u6838\u5fc3\u77e5\u8bc6\u4f53\u7cfb\u603b\u7ed3\u4e0e\u6982\u89c8<\/a><\/p>\n\n\n\n<p class=\"wp-block-paragraph\"><a href=\"https:\/\/zhuanlan.zhihu.com\/p\/68025039\" data-type=\"URL\" data-id=\"https:\/\/zhuanlan.zhihu.com\/p\/68025039\" target=\"_blank\"  rel=\"nofollow\" >\u5982\u4f55\u5728Unity\u4e2d\u9020\u4e00\u4e2aPBR Shader\u8f6e\u5b50<\/a><\/p>\n\n\n\n<p class=\"wp-block-paragraph\"><a href=\"https:\/\/zhuanlan.zhihu.com\/p\/507733341\" data-type=\"URL\" data-id=\"https:\/\/zhuanlan.zhihu.com\/p\/507733341\" target=\"_blank\"  rel=\"nofollow\" >\u3010Free Bird\/URP\u6559\u5b66\u301110.PBR\u6e32\u67d3<\/a><\/p>\n\n\n\n<p class=\"wp-block-paragraph\"><a href=\"https:\/\/zhuanlan.zhihu.com\/p\/453473695\" data-type=\"URL\" data-id=\"https:\/\/zhuanlan.zhihu.com\/p\/453473695\" target=\"_blank\"  rel=\"nofollow\" >\u5b66\u4e60PRB\u8def\u7a0b\uff08\u4e00\u3001\u6838\u5fc3\u7406\u8bba\uff09<\/a><\/p>\n\n\n\n<p class=\"wp-block-paragraph\"><a href=\"https:\/\/learnopengl-cn.github.io\/07%20PBR\/01%20Theory\/\" data-type=\"URL\" data-id=\"https:\/\/learnopengl-cn.github.io\/07%20PBR\/01%20Theory\/\" target=\"_blank\"  rel=\"nofollow\" >LearnOpenGL-PBR<\/a><\/p>\n\n\n\n<h3 class=\"wp-block-heading\">BRDF<\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">Cook-Torrance BRDF\u7684\u955c\u9762\u53cd\u5c04\u90e8\u5206\u5305\u542b\u4e09\u4e2a\u51fd\u6570\uff0c\u6b64\u5916\u5206\u6bcd\u90e8\u5206\u8fd8\u6709\u4e00\u4e2a\u6807\u51c6\u5316\u56e0\u5b50 \u3002\u4e09\u4e2a\u51fd\u6570\u5206\u522b\u4e3a<strong>\u6cd5\u7ebf\u5206\u5e03\u51fd\u6570(Normal&nbsp;Distribution Function)<\/strong>\uff0c<strong>\u83f2\u6d85\u5c14\u65b9\u7a0b(Fresnel Rquation)<\/strong>\u548c<strong>\u51e0\u4f55\u51fd\u6570(Geometry Function)<\/strong>\u3002<\/p>\n\n\n\n<ul class=\"wp-block-list\"><li><strong>\u6cd5\u7ebf\u5206\u5e03\u51fd\u6570<\/strong>\uff1a\u4f30\u7b97\u5728\u53d7\u5230\u8868\u9762\u7c97\u7cd9\u5ea6\u7684\u5f71\u54cd\u4e0b\uff0c\u53d6\u5411\u65b9\u5411\u4e0e\u4e2d\u95f4\u5411\u91cf\u4e00\u81f4\u7684\u5fae\u5e73\u9762\u7684\u6570\u91cf\u3002\u8fd9\u662f\u7528\u6765\u4f30\u7b97\u5fae\u5e73\u9762\u7684\u4e3b\u8981\u51fd\u6570\u3002<\/li><li><strong>\u51e0\u4f55\u51fd\u6570<\/strong>\uff1a\u63cf\u8ff0\u4e86\u5fae\u5e73\u9762\u81ea\u6210\u9634\u5f71\u7684\u5c5e\u6027\u3002\u5f53\u4e00\u4e2a\u5e73\u9762\u76f8\u5bf9\u6bd4\u8f83\u7c97\u7cd9\u7684\u65f6\u5019\uff0c\u5e73\u9762\u8868\u9762\u4e0a\u7684\u5fae\u5e73\u9762\u6709\u53ef\u80fd\u6321\u4f4f\u5176\u4ed6\u7684\u5fae\u5e73\u9762\u4ece\u800c\u51cf\u5c11\u8868\u9762\u6240\u53cd\u5c04\u7684\u5149\u7ebf\u3002<\/li><li><strong>\u83f2\u6d85\u5c14\u65b9\u7a0b<\/strong>\uff1a\u83f2\u6d85\u5c14\u65b9\u7a0b\u63cf\u8ff0\u7684\u662f\u5728\u4e0d\u540c\u7684\u8868\u9762\u89d2\u4e0b\u8868\u9762\u6240\u53cd\u5c04\u7684\u5149\u7ebf\u6240\u5360\u7684\u6bd4\u7387\u3002<\/li><\/ul>\n\n\n\n<p class=\"wp-block-paragraph\"><\/p>\n\n\n\n<h4 class=\"wp-block-heading\">\u6cd5\u7ebf\u5206\u5e03\u51fd\u6570<\/h4>\n\n\n<div class=\"wp-block-image\">\n<figure class=\"aligncenter size-full\"><img decoding=\"async\" src=\"https:\/\/www.acgloby.com\/wp-content\/uploads\/2022\/08\/image-16.png\" alt=\"\" class=\"wp-image-942\"\/><\/figure>\n<\/div>\n\n\n<p class=\"wp-block-paragraph\"><code>h<\/code>\u8868\u793a\u534a\u89c6\u89d2\u5411\u91cf<code>normalize(V + L)<\/code>\uff0c<code>n<\/code>\u8868\u793a\u6cd5\u7ebf\u5411\u91cf\uff0c<code>\u03b1<\/code>\u8868\u793a\u7c97\u7cd9\u5ea6\u3002<\/p>\n\n\n<div class=\"wp-block-image\">\n<figure class=\"aligncenter size-full\"><img decoding=\"async\" src=\"https:\/\/www.acgloby.com\/wp-content\/uploads\/2022\/08\/image-17.png\" alt=\"\" class=\"wp-image-943\"\/><figcaption>\u4e0d\u540c\u7c97\u7cd9\u5ea6\u7684\u89c6\u89c9\u6548\u679c<\/figcaption><\/figure>\n<\/div>\n\n\n<pre class=\"wp-block-code\"><code>float D_GGX_TR(float3 N, float3 H,float a) \n{\n    float a2 = a * a;\n    float NdotH  = max(dot(N, H), 0.0);\n    float NdotH2 = NdotH * NdotH;\n\n    float nom = a2;\n    float denom  = (NdotH2 * (a2 - 1.0) + 1.0);\n    denom = PI * denom * denom;\n\n    return nom \/ denom;\n}<\/code><\/pre>\n\n\n\n<h4 class=\"wp-block-heading\">\u51e0\u4f55\u51fd\u6570<\/h4>\n\n\n<div class=\"wp-block-image\">\n<figure class=\"aligncenter size-full\"><img decoding=\"async\" src=\"https:\/\/www.acgloby.com\/wp-content\/uploads\/2022\/08\/image-18.png\" alt=\"\" class=\"wp-image-948\"\/><\/figure>\n<\/div>\n\n<div class=\"wp-block-image\">\n<figure class=\"aligncenter size-full\"><img decoding=\"async\" src=\"https:\/\/www.acgloby.com\/wp-content\/uploads\/2022\/08\/image-19.png\" alt=\"\" class=\"wp-image-949\"\/><\/figure>\n<\/div>\n\n\n<p class=\"wp-block-paragraph\">\u4e3a\u4e86\u6709\u6548\u7684\u4f30\u7b97\u51e0\u4f55\u90e8\u5206\uff0c\u9700\u8981\u5c06\u89c2\u5bdf\u65b9\u5411\uff08<strong>\u51e0\u4f55\u906e\u853d(Geometry Obstruction)<\/strong>\uff09\u548c\u5149\u7ebf\u65b9\u5411\u5411\u91cf\uff08<strong>\u51e0\u4f55\u9634\u5f71(Geometry Shadowing)<\/strong>\uff09\u90fd\u8003\u8651\u8fdb\u53bb\u3002\u6211\u4eec\u53ef\u4ee5\u4f7f\u7528\u53f2\u5bc6\u65af\u6cd5(Smith\u2019s method)\u6765\u628a\u4e24\u8005\u90fd\u7eb3\u5165\u5176\u4e2d\uff1a<\/p>\n\n\n<div class=\"wp-block-image\">\n<figure class=\"aligncenter size-full\"><img decoding=\"async\" src=\"https:\/\/www.acgloby.com\/wp-content\/uploads\/2022\/08\/image-20.png\" alt=\"\" class=\"wp-image-950\"\/><\/figure>\n<\/div>\n\n<div class=\"wp-block-image\">\n<figure class=\"aligncenter size-full\"><img decoding=\"async\" src=\"https:\/\/www.acgloby.com\/wp-content\/uploads\/2022\/08\/image-21.png\" alt=\"\" class=\"wp-image-951\"\/><figcaption>\u4e0d\u540c\u7c97\u7cd9\u5ea6\u7684\u89c6\u89c9\u6548\u679c<\/figcaption><\/figure>\n<\/div>\n\n\n<pre class=\"wp-block-code\"><code>float GeometrySchlickGGX(float NdotV, float k)\n{\n    float nom = NdotV;\n    float denom = NdotV * (1.0 - k) + k;\n    return nom \/ denom;\n}\n\nfloat GeometrySmith(float3 N, flaot3 V, float3 L, float k)\n{\n    float NdotV = max(dot(N, V), 0.0);\n    float NdotL = max(dot(N, L), 0.0);\n    float ggx1 = GeometrySchlickGGX(NdotV);\n    float ggx2 = GeometrySchlickGGX(NdotL);\n    return ggx1 * ggx2;\n}<\/code><\/pre>\n\n\n\n<h4 class=\"wp-block-heading\">\u83f2\u6d85\u5c14\u65b9\u7a0b<\/h4>\n\n\n<div class=\"wp-block-image\">\n<figure class=\"aligncenter size-full\"><img decoding=\"async\" src=\"https:\/\/www.acgloby.com\/wp-content\/uploads\/2022\/08\/image-22.png\" alt=\"\" class=\"wp-image-952\"\/><\/figure>\n<\/div>\n\n<div class=\"wp-block-image\">\n<figure class=\"aligncenter size-full\"><img decoding=\"async\" src=\"https:\/\/www.acgloby.com\/wp-content\/uploads\/2022\/08\/image-23.png\" alt=\"\" class=\"wp-image-953\"\/><\/figure>\n<\/div>\n\n\n<h4 class=\"wp-block-heading\">\u76f4\u63a5\u5149\u7167<\/h4>\n\n\n\n<pre class=\"wp-block-code\"><code>float3 FresnelSchick(float cosTheta, float3 F0)\n{\n    \/\/return Pow4(1 - NdotV);\n    \/\/return exp2((-5.55473 * NdotV - 6.98316) * NdotV);\n    return F0 + (1.0 - F0) * pow(1.0 - cosTheta, 5.0);\n}<\/code><\/pre>\n\n\n\n<pre class=\"wp-block-code\"><code> half3 F0 = half3(1.00, 0.71, 0.29);\n F0 = lerp(F0,_MainColor,_Metalness);\n half3 F = FresnelSchick(NdotH,F0);<\/code><\/pre>\n\n\n\n<p class=\"wp-block-paragraph\"><code>F<\/code><sub><code>0<\/code><\/sub>\u8868\u793a\u5e73\u9762\u7684\u57fa\u7840\u53cd\u5c04\u7387\uff0c<code>_Metalness<\/code>\u8868\u793a\u5149\u6cfd\u5ea6\u3002\u3001<\/p>\n\n\n\n<h4 class=\"wp-block-heading\">\u95f4\u63a5\u5149\u7167<\/h4>\n\n\n\n<p class=\"wp-block-paragraph\">\u95f4\u63a5\u5149\u901a\u8fc7\u91c7\u6837SH\u7684\u7cfb\u6570\uff0c\u4e3b\u8981\u662f\u53cd\u6620\u4e86\u73af\u5883\u8d34\u56fe\u7684\u7ed3\u679c\uff0c\u63a5\u7740\u548c\u76f4\u63a5\u5149\u8ba1\u7b97\u65b9\u6cd5\u76f8\u4e00\u81f4\uff0c\u4f46\u662f\u5728\u7c97\u7cd9\u5ea6\u65b9\u9762\u4e3a\u4e86\u5339\u914dmipmap\uff0c\u8fdb\u884c\u4e86\u4fee\u9970\u3002\u540c\u65f6\u5728\u76f4\u63a5\u5149\u7684ks\u662f\u83f2\u6d85\u5c14\u9879\uff0c\u4f46\u662f\u5728\u95f4\u63a5\u5149\u9700\u8981\u5355\u72ec\u7b97\u51fa\u95f4\u63a5\u5149\u7684ks\u3002<\/p>\n\n\n\n<pre class=\"wp-block-code\"><code>float3 IndirFresnelSchlick(float cosTheta, float3 F0, float roughness)\n{\n   return F0 + (max(float3(1, 1, 1) * (1 - roughness), F0) - F0) * pow(1.0 - cosTheta, 5.0);\n}<\/code><\/pre>\n\n\n<div class=\"wp-block-image\">\n<figure class=\"aligncenter size-large\"><a href=\"https:\/\/www.acgloby.com\/wp-content\/uploads\/2022\/08\/image-25.png\" alt=\"PBR\" title=\"PBR\"><img decoding=\"async\" src=\"https:\/\/www.acgloby.com\/wp-content\/uploads\/2022\/08\/image-25-1024x476.png\" alt=\"\" class=\"wp-image-957\"\/><\/a><\/figure>\n<\/div>\n\n\n<h3 class=\"wp-block-heading\">\u76f4\u63a5\u5149<\/h3>\n\n\n\n<h4 class=\"wp-block-heading\">\u9ad8\u5149<\/h4>\n\n\n<div class=\"wp-block-image\">\n<figure class=\"aligncenter size-full\"><img decoding=\"async\" src=\"https:\/\/www.acgloby.com\/wp-content\/uploads\/2022\/08\/image-26.png\" alt=\"\" class=\"wp-image-963\"\/><\/figure>\n<\/div>\n\n\n<pre class=\"wp-block-code\"><code>half3 directSpecular = D*G*F\/(4.0*NdotL*NdotV);<\/code><\/pre>\n\n\n\n<h4 class=\"wp-block-heading\">\u6f2b\u53cd\u5c04<\/h4>\n\n\n\n<pre class=\"wp-block-code\"><code>half3 kS = F;\nhalf3 kD = (1-kS)*(1-Metallic);\nhalf3 directDiffuse = kD*Albedo*lightColor*NdotL;<\/code><\/pre>\n\n\n\n<h3 class=\"wp-block-heading\">\u95f4\u63a5\u5149<\/h3>\n\n\n\n<h4 class=\"wp-block-heading\">\u9ad8\u5149<\/h4>\n\n\n\n<figure class=\"wp-block-image size-full\"><img decoding=\"async\" src=\"https:\/\/www.acgloby.com\/wp-content\/uploads\/2022\/08\/image-28.png\" alt=\"\" class=\"wp-image-973\"\/><\/figure>\n\n\n\n<p class=\"wp-block-paragraph\">\u6211\u4eec\u5148\u8ba1\u7b97\u53cd\u5c04\u5c04\u7ebf\u7684\u65b9\u5411\u5bf9cube\u8fdb\u884c\u91c7\u6837\u3002\u6211\u4eec\u8fd8\u9700\u8981\u6839\u636e\u4e0d\u540c\u7684\u7c97\u7cd9\u5ea6\u8fdb\u884c\u91c7\u6837\u4e0d\u540c\u7684\u6a21\u7cca\u5ea6\uff0c\u7c97\u7cd9\u5ea6\u9700\u8981\u4fee\u6539\u4e00\u4e0b\u66f2\u7ebf\u53bb\u62df\u5408\uff0c\u5b83\u5e76\u975e\u7ebf\u6027\uff1b\u6a21\u7cca\u5ea6\u4ece0-6\u603b\u51717\u4e2a\u6a21\u7cca\u7b49\u7ea7\u3002<\/p>\n\n\n\n<pre class=\"wp-block-code\"><code>\/\/\u95f4\u63a5\u5149\u9ad8\u5149 \u53cd\u5c04\u63a2\u9488\nhalf3 IndirSpecularCube(half3 normalWS, half3 viewWS, half roughness, half AO)\n{\n    half3 reflectDirWS = reflect(-viewWS, normalWS);\n    \/\/Unity\u5185\u90e8\u4e0d\u662f\u7ebf\u6027 \u8c03\u6574\u4e0b\u62df\u5408\u66f2\u7ebf\u6c42\u8fd1\u4f3c\n    roughness = roughness * (1.7 - 0.7 * roughness);\n    \/\/\u628a\u7c97\u7cd9\u5ea6remap\u52300-6 7\u4e2a\u9636\u7ea7 \u7136\u540e\u8fdb\u884clod\u91c7\u6837\n    half lod = roughness * 6;\n    \/\/\u6839\u636e\u4e0d\u540c\u7684\u7b49\u7ea7\u8fdb\u884c\u91c7\u6837 \n    half4 specColor = SAMPLE_TEXTURECUBE_LOD(unity_SpecCube0, samplerunity_SpecCube0, reflectDirWS, lod);\n    #if !defined(UNITY_USE_NATIVE_HDR)\n    \/\/\u7528DecodeHDREnvironment\u5c06\u989c\u8272\u4eceHDR\u7f16\u7801\u4e0b\u89e3\u7801\u3002\u53ef\u4ee5\u770b\u5230\u91c7\u6837\u51fa\u7684rgbm\u662f\u4e00\u4e2a4\u901a\u9053\u7684\u503c\uff0c\u6700\u540e\u4e00\u4e2am\u5b58\u7684\u662f\u4e00\u4e2a\u53c2\u6570\uff0c\n    \/\/\u89e3\u7801\u65f6\u5c06\u524d\u4e09\u4e2a\u901a\u9053\u8868\u793a\u7684\u989c\u8272\u4e58\u4e0axM^y\uff0cx\u548cy\u90fd\u662f\u7531\u73af\u5883\u8d34\u56fe\u5b9a\u4e49\u7684\u7cfb\u6570\uff0c\u5b58\u50a8\u5728unity_SpecCube0_HDR\u8fd9\u4e2a\u7ed3\u6784\u4e2d\u3002\n    return DecodeHDREnvironment(specColor, unity_SpecCube0_HDR) * AO;\n    #else\n    return specColor.rgb * AO;\n    #endif\n}\n<\/code><\/pre>\n\n\n\n<p class=\"wp-block-paragraph\">\u6211\u4eec\u8fd8\u9700\u8981\u8ba1\u7b97\u4e00\u4e2a\u95f4\u63a5\u9ad8\u5149\u7684\u5f71\u54cd\u56e0\u5b50\uff0c\u4e00\u822c\u6765\u8bf4\u662f\u6309\u7167\u4e00\u5f20\u73b0\u6210\u7684LUT\u56fe\u50cf\u8fdb\u884c\u91c7\u6837\uff0c\u91c7\u6837UV\u7684U\u65b9\u5411\u4e3aNdotV\uff0cV\u65b9\u5411\u4e3a\u7c97\u7cd9\u5ea6\u6765\u5f97\u5230\u6211\u4eec\u9700\u8981\u7684\u5f71\u54cd\u56e0\u5b50\u3002 <\/p>\n\n\n<div class=\"wp-block-image\">\n<figure class=\"aligncenter size-full\"><img decoding=\"async\" src=\"https:\/\/www.acgloby.com\/wp-content\/uploads\/2022\/08\/image-29.png\" alt=\"\" class=\"wp-image-974\"\/><\/figure>\n<\/div>\n\n\n<p class=\"wp-block-paragraph\">\u4f46\u662f\u91c7\u6837\u8d34\u56fe\u7684\u8fc7\u7a0b\u975e\u5e38\u8017\uff0cunity\u4f7f\u7528\u7684\u66f2\u7ebf\u62df\u5408\u53bb\u5f97\u5230\u7ed3\u679c\u3002<\/p>\n\n\n\n<pre class=\"wp-block-code\"><code>\/\/\u95f4\u63a5\u9ad8\u5149 \u66f2\u7ebf\u62df\u5408 \u653e\u5f03LUT\u91c7\u6837\u800c\u4f7f\u7528\u66f2\u7ebf\u62df\u5408\nhalf3 IndirSpecularFactor(half roughness,half smoothness,half3 BRDFSpecular,half3 F0,half NdotV)\n{\n    #ifdef UNITY_COLORSPACE_GAMMA\n    half surReduction = 1 - 0.28 * roughness * roughness;\n    #else\n    half surReduction = 1 \/ (roughness * roughness + 1);\n    #endif\n    \/\/Lighting.hlsl 274\u884c\n    #if defined(SHADER_API_GLES)\n    half reflectivity = BRDFSpecular.r;\n    #else\n    half reflectivity = max(max(BRDFSpecular.r, BRDFSpecular.g), BRDFSpecular.b);\n    #endif\n    half grazingTSection = saturate(reflectivity + smoothness);\n    \/\/lighting.hlsl\u7b2c512\u884c\n    half fresnel = Pow4(1 - NdotV);\n    return lerp(F0, grazingTSection, fresnel) * surReduction;\n}\n<\/code><\/pre>\n\n\n\n<pre class=\"wp-block-code\"><code>\/\/\u95f4\u63a5\u5149\u9ad8\u5149\nhalf3 indirSpecularCubeColor = IndirSpecularCube(N,V,Roughness,Ao);\nhalf3 indirSpecularCubeFactor = IndirSpecularFactor(Roughness,Smoothness,directSpecular,F0,NdotV);\nhalf3 indirSpecularColor = indirSpecularCubeColor * indirSpecularCubeFactor;<\/code><\/pre>\n\n\n\n<p class=\"wp-block-paragraph\"><\/p>\n\n\n\n<h4 class=\"wp-block-heading\">\u6f2b\u53cd\u5c04<\/h4>\n\n\n\n<p class=\"wp-block-paragraph\">\u57fa\u4e8e\u56fe\u50cf\u7684\u5149\u7167(Image based lighting, IBL)\u662f\u4e00\u7c7b\u5149\u7167\u6280\u672f\u7684\u96c6\u5408\u3002\u5c06\u5468\u56f4\u73af\u5883\u6574\u4f53\u89c6\u4e3a\u4e00\u4e2a\u5927\u5149\u6e90\u3002IBL \u901a\u5e38\u4f7f\u7528\uff08\u53d6\u81ea\u73b0\u5b9e\u4e16\u754c\u6216\u4ece3D\u573a\u666f\u751f\u6210\u7684\uff09\u73af\u5883\u7acb\u65b9\u4f53\u8d34\u56fe (Cubemap) \uff0c\u6211\u4eec\u53ef\u4ee5\u5c06\u7acb\u65b9\u4f53\u8d34\u56fe\u7684\u6bcf\u4e2a\u50cf\u7d20\u89c6\u4e3a\u5149\u6e90\uff0c\u5728\u6e32\u67d3\u65b9\u7a0b\u4e2d\u76f4\u63a5\u4f7f\u7528\u5b83\u3002\u8fd9\u79cd\u65b9\u5f0f\u53ef\u4ee5\u6709\u6548\u5730\u6355\u6349\u73af\u5883\u7684\u5168\u5c40\u5149\u7167\u548c\u6c1b\u56f4\uff0c\u4f7f\u7269\u4f53\u66f4\u597d\u5730\u878d\u5165\u5176\u73af\u5883\u3002<\/p>\n\n\n<div class=\"wp-block-image\">\n<figure class=\"aligncenter size-full\"><img decoding=\"async\" src=\"https:\/\/www.acgloby.com\/wp-content\/uploads\/2022\/08\/image-27-e1660551331983.png\" alt=\"\" class=\"wp-image-964\"\/><\/figure>\n<\/div>\n\n<div class=\"wp-block-image\">\n<figure class=\"aligncenter size-full\"><img decoding=\"async\" src=\"https:\/\/www.acgloby.com\/wp-content\/uploads\/2022\/08\/image-30.png\" alt=\"\" class=\"wp-image-975\"\/><\/figure>\n<\/div>\n\n<div class=\"wp-block-image\">\n<figure class=\"aligncenter size-full\"><img decoding=\"async\" src=\"https:\/\/www.acgloby.com\/wp-content\/uploads\/2022\/08\/3030de074bf3020523e0dec2f3a30db4.jpg\" alt=\"\" class=\"wp-image-965\"\/><\/figure>\n<\/div>\n\n\n<p class=\"wp-block-paragraph\">\u5c06\u6bcf\u4e2a\u65b9\u5411\u4e0a\u8d34\u56fe\u8fdb\u884c\u91c7\u6837\u5377\u79ef\u5f97\u5230\u56fe\u7247\u53f3\u8fb9\u7684\u6548\u679c\uff0cUnity\u5df2\u7ecf\u5e2e\u6211\u4eec\u628acubemap\u7684\u6570\u636e\u5904\u7406\u597d\u5b58\u8d77\u6765\u4e86\u3002<\/p>\n\n\n\n<pre class=\"wp-block-code\"><code>\/\/ SH lighting environment\nhalf4 unity_SHAr;\nhalf4 unity_SHAg;\nhalf4 unity_SHAb;\nhalf4 unity_SHBr;\nhalf4 unity_SHBg;\nhalf4 unity_SHBb;\nhalf4 unity_SHC;<\/code><\/pre>\n\n\n\n<pre class=\"wp-block-code\"><code>float3 SH_IndirectionDiffuse(float3 normalWS)\n{\n    float4 SHCoefficients&#91;7];\n    SHCoefficients&#91;0]=unity_SHAr;\n    SHCoefficients&#91;1]=unity_SHAg;\n    SHCoefficients&#91;2]=unity_SHAb;\n    SHCoefficients&#91;3]=unity_SHBr;\n    SHCoefficients&#91;4]=unity_SHBg;\n    SHCoefficients&#91;5]=unity_SHBb;\n    SHCoefficients&#91;6]=unity_SHC;\n    float3 color=SampleSH9(SHCoefficients,normalWS);\n    return max(0,color);\n}\n<\/code><\/pre>\n\n\n\n<pre class=\"wp-block-code\"><code>half3 shColor = SH_IndirectionDiffuse(N)*Ao;\nhalf3 indirKS = IndirFresnelSchlick(NdotV,F0,Roughness);\nhalf3 indirKD = (1-indirKS)*(1-Metallic);\nhalf3 indirDiffColor = shColor*indirKD*Albedo;<\/code><\/pre>\n\n\n\n<p class=\"wp-block-paragraph\">\u4ee3\u7801Github\uff1a<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">[github repo=\"acgloby\/LearnURP\"]<\/p>\n\n\n\n<p class=\"wp-block-paragraph\"><\/p>\n\n\n\n<div style=\"height:100px\" aria-hidden=\"true\" class=\"wp-block-spacer\"><\/div>\n\n\n\n<p class=\"wp-block-paragraph\"><\/p>\n\n\n\n<p class=\"wp-block-paragraph\"><\/p>\n","protected":false},"excerpt":{"rendered":"<p>PBR\u7406\u8bba \u3010\u57fa\u4e8e\u7269\u7406\u7684\u6e32\u67d3\uff08PBR\uff09\u767d\u76ae\u4e66\u3011\uff08\u4e00\uff09 \u5f00\u7bc7\uff1aPBR\u6838\u5fc3\u77e5\u8bc6\u4f53\u7cfb\u603b\u7ed3\u4e0e\u6982\u89c8 \u5982\u4f55\u5728Unity\u4e2d\u9020\u4e00\u4e2aPBR Shad &#8230;<\/p>\n","protected":false},"author":1,"featured_media":977,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"emotion":"","emotion_color":"","title_style":"","license":"","footnotes":""},"categories":[3],"tags":[],"class_list":["post-940","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-graphics"],"_links":{"self":[{"href":"https:\/\/www.acgloby.com\/index.php\/wp-json\/wp\/v2\/posts\/940","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.acgloby.com\/index.php\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.acgloby.com\/index.php\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.acgloby.com\/index.php\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.acgloby.com\/index.php\/wp-json\/wp\/v2\/comments?post=940"}],"version-history":[{"count":0,"href":"https:\/\/www.acgloby.com\/index.php\/wp-json\/wp\/v2\/posts\/940\/revisions"}],"wp:attachment":[{"href":"https:\/\/www.acgloby.com\/index.php\/wp-json\/wp\/v2\/media?parent=940"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.acgloby.com\/index.php\/wp-json\/wp\/v2\/categories?post=940"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.acgloby.com\/index.php\/wp-json\/wp\/v2\/tags?post=940"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}