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03-UnrealEngine/Rendering/RenderingPipeline/Lighting/Lighting阶段的ShadowMap逻辑.md

@@ -1,65 +0,0 @@
----
-title: Lighting阶段的ShadowMap逻辑
-date: 2023-04-10 14:45:45
-excerpt: 
-tags: 
-rating: ⭐
----
-
-## PS Parameter
-`FDeferredLightPS::FParameters GetDeferredLightPSParameters()`
-
-- LightAttenuationTexture = ShadowMaskTexture ? ShadowMaskTexture : WhiteDummy;
-- One pass projection
-	- VirtualShadowMap = VirtualShadowMapUniformBuffer;
-	- VirtualShadowMapId = VirtualShadowMapId;
-	- ShadowMaskBits = ShadowMaskBits ? ShadowMaskBits : GSystemTextures.GetZeroUIntDummy(GraphBuilder);
-
-最后输出
-- SceneColorTexture  
-- SceneDepthTexture
-
-## Lighting阶段中VSM 渲染函数
-RenderDeferredShadowProjections()，输出`ScreenShadowMaskTexture`。
-
-## 问题所在
-LightAttenuation
-- x：整个场景的方向光阴影。
-- y：整个场景的方向光SSS阴影。
-- z：Light function + per-object shadows
-- w：per-object SSS shadowing in w
-
-zw用于非方向光或者移动端渲染路径。
-```c++
-if (LightData.bRadialLight || SHADING_PATH_MOBILE)  
-{  
-   // Remapping the light attenuation buffer (see ShadowRendering.cpp)  
-  
-   Shadow.SurfaceShadow = LightAttenuation.z * StaticShadowing;  
-   // SSS uses a separate shadowing term that allows light to penetrate the surface  
-   //@todo - how to do static shadowing of SSS correctly?   Shadow.TransmissionShadow = LightAttenuation.w * StaticShadowing;  
-  
-   Shadow.TransmissionThickness = LightAttenuation.w;  
-}  
-else  
-{  
-   // Remapping the light attenuation buffer (see ShadowRendering.cpp)  
-   // Also fix up the fade between dynamic and static shadows   // to work with plane splits rather than spheres.  
-   float DynamicShadowFraction = DistanceFromCameraFade(SceneDepth, LightData);  
-   // For a directional light, fade between static shadowing and the whole scene dynamic shadowing based on distance + per object shadows  
-   Shadow.SurfaceShadow = lerp(LightAttenuation.x, StaticShadowing, DynamicShadowFraction);  
-   // Fade between SSS dynamic shadowing and static shadowing based on distance  
-   Shadow.TransmissionShadow = min(lerp(LightAttenuation.y, StaticShadowing, DynamicShadowFraction), LightAttenuation.w);  
-  
-   Shadow.SurfaceShadow *= LightAttenuation.z;  
-   Shadow.TransmissionShadow *= LightAttenuation.z;  
-  
-   // Need this min or backscattering will leak when in shadow which cast by non perobject shadow(Only for directional light)  
-   Shadow.TransmissionThickness = min(LightAttenuation.y, LightAttenuation.w);  
-}
-```
-
-
-**DeferredLightingCommon.ush**与**DeferredLightPixelShaders.usf**中的**LightAttenuation**即为ShadowMap数据。具体可以参考**GetLightAttenuationFromShadow()**，可以看得出EPIC之后打算通过抖动来消除VSM的阴影锯齿。
-
-主要的阴影效果由**LightAttenuation**与ShadingModels.ush中的NoL提供。我们只需要调整自阴影也就是z通道，其他的整个场景的阴影。

03-UnrealEngine/卡通渲染相关资料/卡通渲染开发总览.md

@@ -117,6 +117,8 @@ rating: ⭐⭐⭐
 11. [ ] 阴影控制
 	1. [ ] 控制深度偏移
 	2. [ ] CustomDepth制作头发阴影偏移效果哦 https://zhuanlan.zhihu.com/p/689578355
+	3. [ ] ContactShadow接触阴影实现衣服细节的DetailShadow
+	4. [ ] 半程阴影
 12. [ ] ToonTranslucent
 	1. [ ] 通过模仿SingleLayerWater实现折射效果 https://zhuanlan.zhihu.com/p/657928532
 	2. [ ] 眉眼细节 [[幻塔-眉眼细节.png]]