Texture Streaming的使用疑问

1）Texture Streaming的使用疑问
​2）Unity 3D场景UI被打断合批的原因
3）Asset Provider和Asset Bundle Provider的意义
4）Addressables更新资源时只加载最初始资源
5）描边算法显示问题

这是第246篇UWA技术知识分享的推送。今天我们继续为大家精选了若干和开发、优化相关的问题，建议阅读时间10分钟，认真读完必有收获。

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Editor

Q：Unity 2019.2 Texture Streaming在Editor下不生效吗？按照Unity官方介绍，可以在SceneView里面Debug Texture Streaming。但是实际上切换过去会变成浅蓝色/深蓝色，并没有其他任何变化。有人遇到相同的情况吗？

A：1.需要测试脚本才能知道节省了多少内存，场景是看不出来的。

using System;
using UnityEditor;
using UnityEngine;

public class ShowTextureStreamingSummary : MonoBehaviour
{
    public float X = 10;
    public float Y = 20;
    public int MemoryBudgetPercentThreshold = 80;
    public int TextureStreamingPercentThreshold = 50;
    private ulong HighestDesiredTextureMemory;
    private Rect TextRect;

    public void Start()
    {
        HighestDesiredTextureMemory = 0;
        Texture.streamingTextureDiscardUnusedMips = false;
      QualitySettings.masterTextureLimit = 2;//强制等级为2，为了配合下面的测试脚本
    }

    public string HumanReadableSize(ulong size)
    {
        return string.Format("{0:0.0}M", (float)size / (float)(1024 * 1024));
    }

    void ShowText(string text)
    {
        float yInc = GUI.skin.font.lineHeight;
        GUI.Label(TextRect, text);
        TextRect.y += yInc;
    }

    public void OnGUI()
    {
        TextRect = new Rect(X, Y, Screen.width - X, Screen.height - Y);
        GUI.color = Color.red;
        if (!SystemInfo.supportsMipStreaming)
            ShowText("Texture streaming unsupported");
        if (!QualitySettings.streamingMipmapsActive)
            ShowText("Texture streaming disabled");
        else if (QualitySettings.streamingMipmapsMemoryBudget == 0)
            ShowText("No texture streaming budget");
        else if (Texture.totalTextureMemory == 0)
            ShowText("No texture memory needed");
        else
        {
            // Reduced highest memory usage
            if (Texture.desiredTextureMemory > HighestDesiredTextureMemory)
                HighestDesiredTextureMemory = Texture.desiredTextureMemory;

            // Show stats
            ulong budget = (ulong)(1024 * 1024 * QualitySettings.streamingMipmapsMemoryBudget);
            float percentUsed = (float)(100 * Texture.desiredTextureMemory) / (float)budget;
            ShowText(string.Format("Memory budget utilisation {0:0.0}% of {1} texture budget", percentUsed, HumanReadableSize(budget)));

            if (HighestDesiredTextureMemory > budget)
            {
                ulong memoryExcess = HighestDesiredTextureMemory - budget;
                ShowText(string.Format("Memory exceeds budget by {0}", HumanReadableSize(memoryExcess)));
            }
            else
            {
                ulong memorySaving = Texture.totalTextureMemory - HighestDesiredTextureMemory;
                float percentReduction = (float)(100 * HighestDesiredTextureMemory) / (float)Texture.totalTextureMemory;
                ShowText(string.Format("Memory saving at least {0} with streaming enabled ( at {1:0.0}% of original {2}) - ignoring caching", HumanReadableSize(memorySaving), percentReduction, HumanReadableSize(Texture.totalTextureMemory)));
            }

            // Advice section
#if UNITY_EDITOR
            ShowText("Run in standalone app for accurate figures. When run in Play Mode the stats are biased by editor textures");
#endif                
            if (percentUsed < (float)MemoryBudgetPercentThreshold)
                ShowText(string.Format("Reduce the Memory Budget closer to {0}", HumanReadableSize(Texture.desiredTextureMemory)));
            else if (Texture.desiredTextureMemory > budget)
                ShowText(string.Format("Raise Memory Budget above {0}", HumanReadableSize(Texture.desiredTextureMemory)));
           
            float percentStreaming = (float)(100 * (Texture.totalTextureMemory - Texture.nonStreamingTextureMemory)) / (float)Texture.totalTextureMemory;
            if (percentStreaming < (float)TextureStreamingPercentThreshold)
                ShowText(string.Format("Mark more textures streaming to improve savings ({0:0.0}% texture memory marked as streaming)", percentStreaming));

            if (!Texture.streamingTextureDiscardUnusedMips)
                ShowText("Consider turning on Texture.streamingTextureDiscardUnusedMips to analyse without cached textures");

            ShowText(string.Format("desiredTextureMemory {0}", HumanReadableSize(Texture.desiredTextureMemory)));
            ShowText(string.Format("nonStreamingTextureMemory {0}", HumanReadableSize(Texture.nonStreamingTextureMemory)));
            ShowText(string.Format("totalTextureMemory {0}", HumanReadableSize(Texture.totalTextureMemory)));
        }
    }
}

2.Game窗口下，查看哪位纹理使用了Streaming。显示绿的是使用了Streaming；蓝色的是未开启Streaming；红色的是还没使用Streaming。

using UnityEngine;

public class TextureStreamingDebug : MonoBehaviour
{
    public Camera m_MainCamera;
    public Shader m_ReplacementShader;
    public bool m_ActivateDebugShader;
    private bool m_DebugShaderActive = false;
    private RenderingPath originalRenderingPath;

    void Start()
    {
        // Grab camera from self if none set
        if (!m_MainCamera)
            m_MainCamera = GetComponent<Camera>();

        if (m_MainCamera)
            originalRenderingPath = m_MainCamera.renderingPath;
    }

    void Update()
    {
        if (!m_MainCamera || !m_ReplacementShader)
            return;

#if UNITY_STANDALONE_WIN || UNITY_EDITOR
        if (Input.GetKeyDown(KeyCode.Space))
            m_ActivateDebugShader ^= true;
#else
        if (Input.GetButtonDown("Fire1"))
            m_ActivateDebugShader ^= true;
#endif

        if (m_ActivateDebugShader != m_DebugShaderActive)
        {
            if (m_ActivateDebugShader)
            {
                m_MainCamera.renderingPath = RenderingPath.Forward;
                m_MainCamera.SetReplacementShader(m_ReplacementShader, "RenderType");
            }
            else
            {
                m_MainCamera.renderingPath = originalRenderingPath;
                m_MainCamera.ResetReplacementShader();
            }

            m_DebugShaderActive = m_ActivateDebugShader;
        }

        if (m_DebugShaderActive)
            Texture.SetStreamingTextureMaterialDebugProperties();
    }
}

对应Shader：

Shader "Hidden/Scene View Show Texture Streaming" 
{
    Properties 
    {
        _MainTex ("", 2D) = "white" {}
        _Control ("Control (RGBA)", 2D) = "red" {}
        _Splat3 ("Layer 3 (A)", 2D) = "white" {}
        _Splat2 ("Layer 2 (B)", 2D) = "white" {}
        _Splat1 ("Layer 1 (G)", 2D) = "white" {}
        _Splat0 ("Layer 0 (R)", 2D) = "white" {}
        _BaseMap ("", 2D) = "white" {}
        _Cutoff ("Cutoff", float) = 0.5
    }
 
CGINCLUDE
// Common code used by most of the things below
#include "UnityCG.cginc"
struct v2f 
{
    float4 pos : SV_POSITION;
    float2 uv : TEXCOORD0;
};
uniform float4 _MainTex_ST;
uniform float4 _MainTex_TexelSize;
uniform float4 _MainTex_MipInfo;
 
UNITY_DECLARE_TEX2D(_MainTex);
UNITY_DECLARE_TEX2D(_SceneViewMipcolorsTexture);
 
uint GetMipCount(Texture2D tex)
{
#if defined(SHADER_API_D3D11) || defined(SHADER_API_D3D12) || defined(SHADER_API_D3D11_9X) || defined(SHADER_API_XBOXONE) || defined(SHADER_API_PSSL)
    #define MIP_COUNT_SUPPORTED 1
#endif
#if (defined(SHADER_API_OPENGL) || defined(SHADER_API_VULKAN)) && !defined(SHADER_STAGE_COMPUTE)
    // OpenGL only supports textureSize for width, height, depth
    // textureQueryLevels (GL_ARB_texture_query_levels) needs OpenGL 4.3 or above and doesn't compile in compute shaders
    // tex.GetDimensions converted to textureQueryLevels
    #define MIP_COUNT_SUPPORTED 1
#endif
    // Metal doesn't support high enough OpenGL version
 
#if defined(MIP_COUNT_SUPPORTED)
    uint mipLevel, width, height, mipCount;
    mipLevel = width = height = mipCount = 0;
    tex.GetDimensions(mipLevel, width, height, mipCount);
    return mipCount;
#else
    return 0;
#endif
}
 
float4 GetStreamingMipColor(uint mipCount, float4 mipInfo)
{
    // alpha is amount to blend with source color (0.0 = use original, 1.0 = use new color)
 
    // mipInfo :
    // x = quality setings minStreamingMipLevel
    // y = original mip count for texture
    // z = desired on screen mip level
    // w = loaded mip level
    uint originalTextureMipCount = uint(mipInfo.y);
 
    // If material/shader mip info (original mip level) has not been set it’s either not a streamed texture 
    // or no renderer is updating it
    if (originalTextureMipCount == 0)
        return float4(0.0, 0.0, 1.0, 0.5);
 
    uint desiredMipLevel = uint(mipInfo.z);
    uint mipCountDesired = uint(originalTextureMipCount)-uint(desiredMipLevel);
    if (mipCount == 0)
    {
        // Can't calculate, use the passed value
        mipCount = originalTextureMipCount - uint(mipInfo.w);
    }
 
    if (mipCount < mipCountDesired)
    {
        // red tones when not at the desired mip level (reduction due to budget). Brighter is further from original, alpha 0 when at desired
        float ratioToDesired = float(mipCount) / float(mipCountDesired);
            return float4(1.0, 0.0, 0.0, 1.0 - ratioToDesired);
    }
    else if (mipCount >= originalTextureMipCount)
    {
        // original color when at (or beyond) original mip count
        return float4(1.0, 1.0, 1.0, 0.0);
    }
    else
    {
        // green tones when not at the original mip level. Brighter is closer to original, alpha 0 when at original
        float ratioToOriginal = float(mipCount) / float(originalTextureMipCount);
        return float4(0.0, 1.0, 0.0, 1.0 - ratioToOriginal);
    }
}
 
float3 GetDebugStreamingMipColorBlended(float3 originalColor, Texture2D tex, float4 mipInfo)
{
    uint mipCount = GetMipCount(tex);
    float4 mipColor = GetStreamingMipColor(mipCount, mipInfo);
    return lerp(originalColor, mipColor.rgb, mipColor.a);
}
 
v2f vert( appdata_base v ) 
{
    v2f o;
    o.pos = UnityObjectToClipPos(v.vertex);
    o.uv = TRANSFORM_TEX(v.texcoord,_MainTex);
  
    return o;
}
 
fixed4 frag(v2f i) : COLOR
{
    fixed4 col = UNITY_SAMPLE_TEX2D(_MainTex, i.uv);
    half4 res;
    res.rgb = GetDebugStreamingMipColorBlended(col.rgb, _MainTex, _MainTex_MipInfo);
    res.a = col.a;
    return res;
}
 
struct v2fGrass 
{
    float4 pos : SV_POSITION;
    fixed4 color : COLOR;
    float2 uv : TEXCOORD0;
};
 
fixed4 fragGrass(v2fGrass i) : COLOR
{
    fixed4 col = UNITY_SAMPLE_TEX2D(_MainTex, i.uv);
    half4 res;
    res.rgb = GetDebugStreamingMipColorBlended(col.rgb, _MainTex, _MainTex_MipInfo);
    res.a = col.a * i.color.a;
    return res;
}
ENDCG
 
SubShader 
{
    Tags { "ForceSupported" = "True" "RenderType"="Opaque" }
    Pass 
    {
CGPROGRAM
 
// As both normal opaque shaders and terrain splat shaders
// have "Opaque" render type, we need to do some voodoo
// to make both work.
 
#pragma vertex vertWTerrain
#pragma fragment fragWTerrain
#pragma target 2.0
#pragma exclude_renderers gles
 
struct v2fterr 
{
    float4 pos : SV_POSITION;
    float2 uvnormal : TEXCOORD0;
    float4 uv[3] : TEXCOORD2;
    float nonterrain  : TEXCOORD5;
};
 
uniform float4 _Splat0_ST,_Splat1_ST,_Splat2_ST,_Splat3_ST,_Splat4_ST;
uniform float4 _Splat0_TexelSize,_Splat1_TexelSize,_Splat2_TexelSize,_Splat3_TexelSize,_Splat4_TexelSize;
uniform float4 _BaseMap_TexelSize;
 
v2fterr vertWTerrain( appdata_base v ) 
{
    v2fterr o;
    o.pos = UnityObjectToClipPos(v.vertex);
    // assume it's not a terrain if _Splat0_TexelSize is not set up.
    float nonterrain = _Splat0_TexelSize.z==0.0 ? 1:0;
    // collapse/don't draw terrain's add pass in this mode, since it looks really bad if first pass
    // and add pass blink depending on which gets drawn first with this replacement shader
    // TODO: make it display mips properly even for two-pass terrains. 
    o.pos *= _MainTex_TexelSize.z==0.0 && _Splat0_TexelSize.z!=0.0 ? 0 : 1;
    // normal texture UV
    o.uvnormal = TRANSFORM_TEX(v.texcoord,_MainTex);
    // terrain splat UVs
    float2 baseUV = v.texcoord.xy;
    o.uv[0].xy = baseUV;
    o.uv[0].zw = half2(0,0);
    o.uv[1].xy = TRANSFORM_TEX (baseUV, _Splat0);
    o.uv[1].zw = TRANSFORM_TEX (baseUV, _Splat1);
    o.uv[2].xy = TRANSFORM_TEX (baseUV, _Splat2);
    o.uv[2].zw = TRANSFORM_TEX (baseUV, _Splat3);
  
    o.nonterrain = nonterrain;
    return o;
}
UNITY_DECLARE_TEX2D(_Control);
UNITY_DECLARE_TEX2D(_Splat0);
UNITY_DECLARE_TEX2D(_Splat1);
UNITY_DECLARE_TEX2D(_Splat2);
UNITY_DECLARE_TEX2D(_Splat3);
UNITY_DECLARE_TEX2D(_BaseMap);
fixed4 fragWTerrain(v2fterr i) : COLOR
{
    // sample regular texture
    fixed4 colnormal = UNITY_SAMPLE_TEX2D(_MainTex, i.uvnormal);
  
    // sample splatmaps
    half4 splat_control = UNITY_SAMPLE_TEX2D(_Control, i.uv[0].xy);
    half3 splat_color = splat_control.r * UNITY_SAMPLE_TEX2D(_Splat0, i.uv[1].xy).rgb;
    splat_color += splat_control.g * UNITY_SAMPLE_TEX2D(_Splat1, i.uv[1].zw).rgb;
    splat_color += splat_control.b * UNITY_SAMPLE_TEX2D(_Splat2, i.uv[2].xy).rgb;
    splat_color += splat_control.a * UNITY_SAMPLE_TEX2D(_Splat3, i.uv[2].zw).rgb;
  
    // lerp between normal and splatmaps
    half3 col = lerp(splat_color, colnormal.rgb, (half)i.nonterrain);
 
    half4 res;
    // TODO: Take splat mips into account
    res.rgb = GetDebugStreamingMipColorBlended(col.rgb, _MainTex, _MainTex_MipInfo);
    res.a = colnormal.a;
  
    return res;
}
ENDCG
    }
}
 
SubShader 
{
    Tags { "ForceSupported" = "True" "RenderType"="Transparent" }
    Pass 
    {
        Cull Off
CGPROGRAM
#pragma vertex vert
#pragma fragment frag
#pragma target 2.0
#pragma exclude_renderers gles
ENDCG
    }
}
 
SubShader 
{
    Tags { "ForceSupported" = "True" "RenderType"="TransparentCutout" }
    Pass 
    {
        AlphaTest Greater [_Cutoff]
CGPROGRAM
#pragma vertex vert
#pragma fragment frag
#pragma target 2.0
#pragma exclude_renderers gles
ENDCG
    }
}
 
SubShader 
{
    Tags { "ForceSupported" = "True" "RenderType"="TreeBark" }
    Pass 
    {
CGPROGRAM
#pragma vertex vertTreeBark
#pragma fragment frag
#pragma target 2.0
#pragma exclude_renderers gles
#include "UnityCG.cginc"
#include "UnityBuiltin3xTreeLibrary.cginc"
v2f vertTreeBark (appdata_full v) 
{
    v2f o;
    TreeVertBark(v);
    o.pos = UnityObjectToClipPos(v.vertex);
    o.uv = v.texcoord;
    return o;
}
ENDCG
  }
}
 
SubShader 
{
    Tags { "ForceSupported" = "True" "RenderType"="TreeLeaf" }
    Pass 
    {
CGPROGRAM
#pragma vertex vertTreeLeaf
#pragma fragment frag
#pragma target 2.0
#pragma exclude_renderers gles
#include "UnityCG.cginc"
#include "UnityBuiltin3xTreeLibrary.cginc"
v2f vertTreeLeaf (appdata_full v) 
{
    v2f o;
    TreeVertLeaf (v);
    o.pos = UnityObjectToClipPos(v.vertex);
    o.uv = v.texcoord;
    return o;
}
ENDCG
        AlphaTest GEqual [_Cutoff]
    }
}
 
SubShader 
{
    Tags { "ForceSupported" = "True" "RenderType"="TreeOpaque" }
    Pass 
    {
CGPROGRAM
#pragma vertex vertTree
#pragma fragment frag
#pragma target 2.0
#pragma exclude_renderers gles
#include "TerrainEngine.cginc"
struct appdata 
{
    float4 vertex : POSITION;
    fixed4 color : COLOR;
    float2 texcoord : TEXCOORD0;
};
v2f vertTree( appdata v ) 
{
    v2f o;
    TerrainAnimateTree(v.vertex, v.color.w);
    o.pos = UnityObjectToClipPos(v.vertex);
    o.uv = v.texcoord;
    return o;
}
ENDCG
    }
} 
 
SubShader 
{
    Tags { "ForceSupported" = "True" "RenderType"="TreeTransparentCutout" }
    Pass 
    {
        Cull Off
CGPROGRAM
#pragma vertex vertTree
#pragma fragment frag
#pragma target 2.0
#pragma exclude_renderers gles
#include "TerrainEngine.cginc"
struct appdata 
{
    float4 vertex : POSITION;
    fixed4 color : COLOR;
    float4 texcoord : TEXCOORD0;
};
v2f vertTree( appdata v ) 
{
    v2f o;
    TerrainAnimateTree(v.vertex, v.color.w);
    o.pos = UnityObjectToClipPos(v.vertex);
    o.uv = v.texcoord;
    return o;
}
ENDCG
        AlphaTest GEqual [_Cutoff]
    }
}
 
SubShader 
{
    Tags { "ForceSupported" = "True" "RenderType"="TreeBillboard" }
    Pass 
    {
        Cull Off
        ZWrite Off
CGPROGRAM
#pragma vertex vertTree
#pragma fragment frag
#pragma target 2.0
#pragma exclude_renderers gles
#include "TerrainEngine.cginc"
v2f vertTree (appdata_tree_billboard v) 
{
    v2f o;
    TerrainBillboardTree(v.vertex, v.texcoord1.xy, v.texcoord.y);
    o.pos = UnityObjectToClipPos(v.vertex);
    o.uv.x = v.texcoord.x;
    o.uv.y = v.texcoord.y > 0;
    return o;
}
ENDCG
      
        SetTexture [_MainTex] { combine primary, texture }
    }
}

SubShader 
{
    Tags { "ForceSupported" = "True" "RenderType"="GrassBillboard" }
    Pass 
    {
        Cull Off
CGPROGRAM
#pragma vertex vertGrass
#pragma fragment fragGrass
#pragma target 2.0
#pragma exclude_renderers gles
#include "TerrainEngine.cginc"
v2fGrass vertGrass (appdata_full v) 
{
    v2fGrass o;
    WavingGrassBillboardVert (v);
    o.color = v.color;
    o.pos = UnityObjectToClipPos(v.vertex);
    o.uv = v.texcoord;
    return o;
}
ENDCG
        AlphaTest Greater [_Cutoff]
    }
}
 
SubShader 
{
    Tags { "ForceSupported" = "True" "RenderType"="Grass" }
    Pass 
    {
        Cull Off
CGPROGRAM
#pragma vertex vertGrass
#pragma fragment fragGrass
#pragma target 2.0
#pragma exclude_renderers gles
#include "TerrainEngine.cginc"
v2fGrass vertGrass (appdata_full v) 
{
    v2fGrass o;
    WavingGrassVert (v);
    o.color = v.color;
    o.pos = UnityObjectToClipPos(v.vertex);
    o.uv = v.texcoord;
    return o;
}
ENDCG
        AlphaTest Greater [_Cutoff]
    }
}
 
Fallback Off
}

感谢牛头人不服@UWA问答社区提供了回答，欢迎大家转至社区交流：
https://answer.uwa4d.com/question/5e986adb8cabe84a011afd27

Rendering

Q：如下图，使用Sprite Renderer做图片和TextMeshPro做文字，使用Unity帧调试器查看，发现第一排三个图片动态合批了，第二排三个图片动态合批了，第三排三个图片动态合批了，但是文字都合不了批，原因是动态批处理在Player Settings中被关闭或在当前环境中被暂时禁用，以避免Z-Fighting。能不能所有图片一个批次，所有文字一个批次？

A1：我的方法是设置Sorting Layer和Order in Layer：

SpriteRenderer -> Additional Settings；
TextMeshPro Text -> Extra Settings。

但这样的缺点是字永远会在图的上面，重叠的时候显示会有问题。

感谢小埃拉@UWA问答社区提供了回答

A2：1.对于普通的Mesh物体的绘制，也就是使用Mesh Renderer绘制的Mesh：在开启了动态合批的情况下，使用相同Material的两个物体，以相邻顺序绘制时，如果满足其他动态合批的条件，即可合批。

题主的文字部分没有合批，是因为没有开启动态合批。看Frame Debugger，题主的渲染管线使用的是SRP，开启动态合批的方式是在RenderPipelineAsset的Inspector面板的Advanced下勾选Dynamic Batching。

至于说为什么图片出现了合批现象，这是因为图片使用Sprite Renderer来绘制，其网格是Unity动态生成的，合批的行为也是Unity内部处理的，不受Dynamic Batching开启与否的影响。

2.其次是控制渲染顺序，使应该合批的物体以相邻顺序渲染，先绘制所有图片，再绘制所有文字。

方法一：按照楼上说的，设置Order in Layer，图片的Order in Layer设置为0，文字为1。

方法二：将所有图片的Render Queue都设置为3000，将所有文字的Render Queue都设置为3001。


效果如下：

感谢Prin@UWA问答社区提供了回答，欢迎大家转至社区交流：
https://answer.uwa4d.com/question/606ec4af6bb31032f9791252

Addressable

Q：请问有没有人知道Addressable 1.17.13中Asset Provider和Asset Bundle Provider这两个选项的意义？

A1：可以搜索下Addressables的源码。可以扩展默认的实现，来自定义自己的下载和加载流程。

[DisplayName(“Assets from Bundles Provider”)]
public class BundledAssetProvider : ResourceProviderBase
[DisplayName(“AssetBundle Provider”)]
public class AssetBundleProvider : ResourceProviderBase

感谢jim@UWA问答社区提供了回答

A2：这个是用来自定义加载AssetBundle和AssetBundle里面的资源的方式，题主可以看下Addressables.CN版本里面的AssetBundleProvider.cs的实现，在这个版本里面添加了解密AssetBundle的方法，算是另外一种加载AssetBundle的方式。

感谢Xuan@UWA问答社区提供了回答，欢迎大家转至社区交流：
https://answer.uwa4d.com/question/605d8334f2c8273bbbf2a5fd

Addressable

Q：问题描述如下：
使用场景：我正通过Addressables实现无需重启游戏的热更新。

问题复现：

• Part1：当前发布的资源为A版本。
• Part2：而后我发布了B版本的资源，打开游戏后，当前还未开始更新，所以加载的资源为A版本。我开始检查Catalog和资源更新，检测到需要更新后，则释放之前加载的所有Handle，开始热更新。再次加载资源，此时为B版本。重启游戏，再次加载资源也是B版本。（这里一切看起来正常）
• Part3：我发布了C版本的资源，此时打开游戏，就出现问题了。我加载的资源是A版本，而不是B版本。（这一步，我认为有问题）我还是紧接着释放之前加载的所有Handle，开始热更新，再次加载资源。C版本的资源也可以被使用。
• Part4：我后来开始怀疑是否是Addressable在联网状态下，自动会去请求Catalog（我已经勾选Disable Catalog Update on Startup）。如果检测到有资源更新，就会使用最初始版本，而不是热更新后的最新版本资源。于是经过我的实验，我把我的资源服务器关掉，它就自动使用热更新后的最新版本。而启动资源服务器后，加载的资源就会是最初始版本，只有在我热更新后，才恢复正常。

期望效果：我既然已经更新资源，不管是什么情况下，这个资源就应该是最新的。而不是莫名其妙地出现了最初始版本的资源。

Unity版本：2020.1.9f1c1
平台：Windows
相关代码：测试Addressables项目
https://gitee.com/dreamCirno/addressable-hotfix-test/tree/master

A1：不知道你用的是哪个版本，建议参考UWA问答中的信息：
https://answer.uwa4d.com/question/5e3b7fe686a39548919837e1

或者看看调用的顺序是不是有问题，我是按照这个顺序调用的：
InitializeAsync->CheckForCatalogUpdates->UpdateCatalogs->GetDownloadSizeAsync->DownloadDependenciesAsync

感谢jim@UWA问答社区提供了回答

A2：从你的描述上看，感觉你这个好像是没更新到B版本的Catalog导致的。

感谢Robot.Huang@UWA问答社区提供了回答

A3：参考如下代码：

using System;
using System.Collections;
using System.Collections.Generic;
using UnityEngine;
using UnityEngine.AddressableAssets;
using UnityEngine.ResourceManagement.AsyncOperations;
using UnityEngine.ResourceManagement.ResourceProviders;
using UnityEngine.UI;
using static UnityEngine.AddressableAssets.Addressables;

public class GameLaunch : MonoBehaviour 
{

    public Action<string> OnStatusTipHasChanged;
    public Action<float> OnDownloadPercentHasChanged;
    public Action<bool> OnDownloadHasResult;

    AsyncOperationHandle<GameObject> handle;
    GameObject obj;

    /// <summary>
    /// 自定义指定待更新检测的 Label 集合
    /// </summary>
    private List<string> mKeys = new List<string>() { "default" };

    public IEnumerator CheckUpdate() 
    {
        bool isNeedUpdateCatalog = false;
        bool isNeedUpdateResources = false;

        // 初始化 Addressable
        var initHandle = Addressables.InitializeAsync();
        yield return initHandle;
        OnStatusTipHasChanged?.Invoke("开始检查更新");
        Debug.LogError("开始检查更新");

        // 检查本地 Catalog 是否为最新版本
        var checkHandle = Addressables.CheckForCatalogUpdates(false);
        yield return checkHandle;
        if (checkHandle.Status == AsyncOperationStatus.Succeeded) {
            OnDownloadPercentHasChanged?.Invoke(1);
            OnStatusTipHasChanged?.Invoke("目录检查完成");
            Debug.LogError("目录检查完成");
        }

        List<string> catalogs = checkHandle.Result;
        if (catalogs != null && catalogs.Count > 0) 
        {
            OnStatusTipHasChanged?.Invoke("检测到目录需要更新");
            Debug.LogError("检测到 Catalogs 需要更新");
            isNeedUpdateCatalog = true;
        } 
        else 
        {
            OnStatusTipHasChanged?.Invoke("检测到目录已是最新");
            Debug.LogError("检测到 Catalogs 已是最新");
        }

        var sizeHandle = Addressables.GetDownloadSizeAsync(mKeys);
        if (sizeHandle.Result > 0) 
        {
            Debug.LogError("检测到有更新资源包");
            OnStatusTipHasChanged?.Invoke("检测到有更新资源包");
            isNeedUpdateResources = true;
        } 
        else 
        {
            Debug.LogError("检测到没有资源更新");
            OnStatusTipHasChanged?.Invoke("检测到没有资源更新");
        }

        OnStatusTipHasChanged?.Invoke("准备进行下一步");

        if (isNeedUpdateCatalog || isNeedUpdateResources) 
        {
            if (isNeedUpdateCatalog) 
            {
                yield return UpdateCatalog(catalogs);
            }
            if (isNeedUpdateResources) 
            {
                yield return UpdateResources();
            }
            OnDownloadHasResult?.Invoke(true);
        } 
        else 
        {
            //StartGame();
            Debug.LogError("开始游戏");
        }
    }

    private void Update() 
    {
        if (Input.GetKeyDown(KeyCode.C)) 
        {
            StartCoroutine(CheckUpdate());
        }
        if (Input.GetKeyDown(KeyCode.L)) 
        {
            handle = Addressables.LoadAssetAsync<GameObject>("Image");
            handle.Completed += param => 
            {
                if (param.Status == AsyncOperationStatus.Succeeded) 
                {
                    Debug.LogError("预加载成功");
                } 
                else 
                {
                    Debug.LogError("预加载失败");
                }
                obj = param.Result;
            };
        }
        if (Input.GetKeyDown(KeyCode.R)) 
        {
            ReleaseCache();
        }
        if (Input.GetKeyDown(KeyCode.Space)) 
        {
            Instantiate(obj, new Vector2(UnityEngine.Random.Range(0, 400), UnityEngine.Random.Range(0, 400)), Quaternion.identity, GameObject.Find("Canvas").transform);
        }
    }

    private IEnumerator UpdateCatalog(List<string> catalogs) 
    {
        var updateHandle = Addressables.UpdateCatalogs(catalogs, false);
        Debug.LogError("开始更新 Catalogs");
        yield return updateHandle;

        Addressables.Release(updateHandle);
    }

    private IEnumerator UpdateResources() 
    {
        ReleaseCache();
        // 需更新大小 > 0，表示需要下载更新
        // 清理旧资源
        //var clearHandle = Addressables.ClearDependencyCacheAsync(mKeys, false);
        //yield return clearHandle;

        // 下载待更新资源
        var downloadHandle = Addressables.DownloadDependenciesAsync(mKeys, MergeMode.Union, false);
        Debug.LogError("开始更新资源");
        while (!downloadHandle.IsDone) 
        {
            DownloadStatus downloadStatus = downloadHandle.GetDownloadStatus();
            OnDownloadPercentHasChanged?.Invoke(downloadStatus.Percent);
            OnStatusTipHasChanged?.Invoke($"下载进度: {downloadStatus.Percent * 100} %");
            Debug.LogError($"下载进度: {downloadStatus.Percent * 100} %");
            yield return null;
        }
        if (downloadHandle.Status == AsyncOperationStatus.Succeeded) 
        {
            OnStatusTipHasChanged?.Invoke($"下载情况：{(downloadHandle.IsDone ? "完成" : "未完成")}");
            Debug.LogError($"下载情况：{(downloadHandle.IsDone ? "完成" : "未完成")}");
        } 
        else 
        {
            OnStatusTipHasChanged?.Invoke($"下载更新包失败");
            Debug.LogError($"下载更新包失败，错误内容：{downloadHandle.OperationException.Message}");
        }
        Addressables.Release(downloadHandle);
    }

    private void ReleaseCache() 
    {
        try 
        {
            Addressables.Release(handle);
            Debug.LogError("释放资源成功");
        } 
        catch (Exception) 
        {
            Debug.LogError("释放资源失败");
        }
    }

}

感谢题主李传东@UWA问答社区提供了回答，欢迎大家转至社区交流：
https://answer.uwa4d.com/question/607152b46bb31032f9791298

Rendering

Q：使用法线描边算法，在一些比较薄的网格上有穿模现象。这是算法问题还是网格问题？应该如何解决？

Shader如图：

A1：比较怀疑两点：
1.是否要Cull Front而不是Cull Back？
2.如果是自己渲染的RenderTexture，是不是深度的精度给的不太够？

感谢王宇@UWA问答社区提供了回答

A2：是这种方法会产生的固有问题，渲染的Backfaces与原有模型发生深度冲突，遮挡模型，造成穿透问题。

解决方法：一种方法是给Backfaces设置Z-offset，让轮廓线埋没到临近的面里。另一种方法是修改Backfaces扩张的法线，使轮廓线（Backfaces）扁平化。

相关参考链接：https://blog.csdn.net/candycat1992/article/details/41120019

感谢Xuan@UWA问答社区提供了回答，欢迎大家转至社区交流：
https://answer.uwa4d.com/question/606ec44f6bb31032f9791251

封面图来源于网络

今天的分享就到这里。当然，生有涯而知无涯。在漫漫的开发周期中，您看到的这些问题也许都只是冰山一角，我们早已在UWA问答网站上准备了更多的技术话题等你一起来探索和分享。欢迎热爱进步的你加入，也许你的方法恰能解别人的燃眉之急；而他山之“石”，也能攻你之“玉”。

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