【内置渲染管线升级UniversalRP】

From Built-in to URP

General Structure (通用结构)
Shader Include Files (着色器包含文件)
Light Modes (灯光模式)
Variants (变体)
Predefined Shader Preprocessor Macros (预定义的着色器宏)
Helpers (辅助宏)
Shadow Mapping (阴影贴图)
Texture/Sampler Declaration Macros (纹理/采样器声明宏)
Built-in Shader Helper Functions (内置着色器辅助函数)
Vertex Transformation Functions (顶点变换函数)
Normal Transformation Functions (法线转换函数)
Generic Helper Functions (通用辅助函数)

General Structure (通用结构)

First of all, add “RenderPipeline” = “UniversalPipeline” to your tags. Next, all URP shaders are written using HLSL embraced by HLSLPROGRAM/ENDHLSL/etc. macros. To avoid headaches, use them as well.

Built-in	URP
CGPROGRAM	HLSLPROGRAM
ENDCG	ENDHLSL
CGINCLUDE	HLSLINCLUDE

Shader Include Files (着色器包含文件)

Content	Built-in	URP
Core	Unity.cginc	Packages/com.unity.render-pipelines.universal/ShaderLibrary/Core.hlsl
Light	AutoLight.cginc	Packages/com.unity.render-pipelines.universal/ShaderLibrary/Lighting.hlsl
Shadows	AutoLight.cginc	Packages/com.unity.render-pipelines.universal/ShaderLibrary/Shadows.hlsl
Surface shaders	Lighting.cginc	None, but you can find a side project for this here

Other useful includes:

Packages/com.unity.render-pipelines.core/ShaderLibrary/SpaceTransforms.hlsl
Packages/com.unity.render-pipelines.universal/ShaderLibrary/ShaderVariablesFunctions.hlsl
Packages/com.unity.render-pipelines.core/ShaderLibrary/Common.hlsl
Packages/com.unity.render-pipelines.universal/ShaderLibrary/Input.hlsl
Packages/com.unity.render-pipelines.core/ShaderLibrary/Color.hlsl
Packages/com.unity.render-pipelines.universal/ShaderLibrary/DeclareDepthTexture.hlsl
Packages/com.unity.render-pipelines.universal/ShaderLibrary/DeclareOpaqueTextue.hlsl

Light Modes (灯光模式)

Built-in	URP
`ForwardBase`	`UniversalForward`
`ForwardAdd`	`Gone`
`Deferred and related`	UniversalGBuffer seems to have just been added to URP
`Vertex and related`	`Gone`
`ShadowCaster`	`ShadowCaster`
`MotionVectors`	`Not suppoted yet`

The other light modes supported are:

DepthOnly
Meta (for lightmap baking)
Universal2D

Variants (变体)

URP support some variants, so depending on the things you are using, you might need to add some #pragma multi_compile for some of the following keywords:

URP 支持一些变体，所以根据你正在使用的东西，你可能需要添加一些 #pragma multi_compile 的一些关键字:

MAINLIGHT_SHADOWS
MAINLIGHT_SHADOWS_CASCADE
ADDITIONALLIGHTS_VERTEX
ADDITIONALLIGHTS
ADDITIONALLIGHT_SHADOWS
SHADOWSSOFT
MIXEDLIGHTING_SUBTRACTIVE

Predefined Shader Preprocessor Macros (预定义的着色器宏)

Helpers (辅助宏)

Built-in	URP
`UNITY_PROJ_COORD(a)`	`Gone. Do a.xy/a.w instead (移除了, 使用a.xy / a.w代替)`
`UNITY_INITIALIZE_OUTPUT(type, name)`	`ZERO_INITIALIZE(type, name)`

Shadow Mapping (阴影贴图)

You must include Packages/com.unity.render-pipelines.universal/ShaderLibrary/Shadows.hlsl

Built-in	URP
`UNITY_DECLARE_SHADOWMAP(tex)`	`TEXTURE2D_SHADOW_PARAM(textureName, samplerName)`
`UNITY_SAMPLE_SHADOW(tex, uv)`	`SAMPLE_TEXTURE2D_SHADOW(textureName, samplerName, coord3)`
`UNITY_SAMPLE_SHADOW_PROJ(tex, uv)`	`SAMPLE_TEXTURE2D_SHADOW(textureName, samplerName, coord4.xyz/coord4.w)`

Texture/Sampler Declaration Macros (纹理/采样器声明宏)

Unity has a bunch of texture/sampler macros to improve cross compatibility between APIs, but people are not used to use them. Those still exist in URP, but now with different names and new additions. I will not put all of them here because it’s a lot, but you can check their definitions per platform in the API includes.

Unity 有一堆纹理/采样宏来改善api之间的交叉兼容性，但人们并不习惯使用它们. 它们仍然存在于URP中，但现在有了不同的名称和新的添加. 我不会把它们全部放在这里，因为它们太多了，但您可以在包含的API中检查每个平台的定义.

Built-in	URP
`UNITY_DECLARE_TEX2D(name)`	`TEXTURE2D(textureName); SAMPLER(samplerName);`
`UNITY_DECLARE_TEX2D_NOSAMPLER(name)`	`TEXTURE2D(textureName);`
`UNITY_DECLARE_TEX2DARRAY(name)`	`TEXTURE2D_ARRAY(textureName); SAMPLER(samplerName);`
`UNITY_SAMPLE_TEX2D(name, uv)`	`SAMPLE_TEXTURE2D(textureName, samplerName, coord2)`
`UNITY_SAMPLE_TEX2D_SAMPLER(name, samplername, uv)`	`SAMPLE_TEXTURE2D(textureName, samplerName, coord2)`
`UNITY_SAMPLE_TEX2DARRAY(name, uv)`	`SAMPLE_TEXTURE2D_ARRAY(textureName, samplerName, coord2, index)`
`UNITY_SAMPLE_TEX2DARRAY_LOD(name, uv, lod)`	`SAMPLE_TEXTURE2D_ARRAY_LOD(textureName, samplerName, coord2, index, lod)`

Important to note that SCREENSPACE_TEXTURE has become TEXTURE2D_X. If you are working on some screen space effect for VR in Single Pass Instanced or Multi-view modes, you must declare the textures used with TEXTURE2D_X. This macro will handle for you the correct texture (array or not) declaration. You also have to sample the textures using SAMPLE_TEXTURE2D_X and use UnityStereoTransformScreenSpaceTex for the uv.

需要注意 SCREENSPACE_TEXTURE 变成了 TEXTURE2D_X. 如果你想要在VR中（Single Pass Instanced 或 Multi-view 模式）制作屏幕效果，你必须使用 TEXTURE2D_X 定义纹理。这个宏会为你处理正确的纹理声明 (是否为数组). 对这个纹理采样的时候必须使用SAMPLE_TEXTURE2D_X，并且对uv使用UnityStereoTransformScreenSpaceTex.

Built-in Shader Helper Functions (内置着色器辅助函数)

You can find them all in Packages/com.unity.render-pipelines.core/ShaderLibrary/SpaceTransforms.hlsl

Vertex Transformation Functions (顶点变换函数)

Built-in	URP
`float4 UnityObjectToClipPos(float3 pos)`	`float4 TransformObjectToHClip(float3 positionOS)`
`float3 UnityObjectToViewPos(float3 pos)`	`TransformWorldToView(TransformObjectToWorld(positionOS))`

Normal Transformation Functions (法线转换函数)

Built-in	URP
`float4 UnityObjectToWorldNormal(float3 pos)`	`float4 TransformObjectToWorldNormal(float3 normalOS)`

Generic Helper Functions (通用辅助函数)

Built-in	URP
`float3 WorldSpaceViewDir (float4 v)`	`float3 GetWorldSpaceViewDir(float3 positionWS)` Include `Packages/com.unity.render-pipelines.universal/ShaderLibrary/ShaderVariablesFunctions.hlsl`
`float3 ObjSpaceViewDir (float4 v)`	Gone. Do `TransformWorldToObject(GetCameraPositionWS())` - objectSpacePosition;
`float2 ParallaxOffset (half h, half height, half3 viewDir)`	Gone? Copy from UnityCG.cginc
`fixed Luminance (fixed3 c)`	`real Luminance(real3 linearRgb)` Include `Packages/com.unity.render-pipelines.core/ShaderLibrary/Color.hlsl`
`fixed3 DecodeLightmap (fixed4 color)`	`real3 DecodeLightmap(real4 encodedIlluminance, real4 decodeInstructions)` Include `Packages/com.unity.render-pipelines.core/ShaderLibrary/EntityLighting.hlsl` `decodeInstructions` is used as `half4(LIGHTMAP_HDR_MULTIPLIER, LIGHTMAP_HDR_EXPONENT, 0.0h, 0.0h)`by URP
`float4 EncodeFloatRGBA (float v)`	Gone? Copy from UnityCG.cginc
`float DecodeFloatRGBA (float4 enc)`	Gone? Copy from UnityCG.cginc
`float2 EncodeFloatRG (float v)`	Gone? Copy from UnityCG.cginc
`float DecodeFloatRG (float2 enc)`	Gone? Copy from UnityCG.cginc
`float2 EncodeViewNormalStereo (float3 n)`	Gone? Copy from UnityCG.cginc
`float3 DecodeViewNormalStereo (float4 enc4)`	Gone? Copy from UnityCG.cginc

https://www.jianshu.com/p/3fef69e2efb6
https://teodutra.com/unity/shaders/urp/graphics/2020/05/18/From-Built-in-to-URP/

作者：admin 创建时间：2022-07-11 14:27
最后编辑：admin 更新时间：2023-04-13 18:03