shader-techniques

Compare original and translation side by side

🇺🇸

Original

English
🇨🇳

Translation

Chinese

Shader Techniques

Shader技术

Shader Pipeline Overview

Shader渲染管线概述

┌─────────────────────────────────────────────────────────────┐
│                    RENDERING PIPELINE                        │
├─────────────────────────────────────────────────────────────┤
│  CPU (Game Logic)                                            │
│       ↓                                                      │
│  VERTEX SHADER                                               │
│  ├─ Transform vertices to clip space                        │
│  ├─ Calculate normals, tangents                             │
│  └─ Pass data to fragment shader                            │
│       ↓                                                      │
│  RASTERIZATION (Fixed function)                              │
│  ├─ Triangle setup                                          │
│  ├─ Pixel coverage                                          │
│  └─ Interpolation                                           │
│       ↓                                                      │
│  FRAGMENT/PIXEL SHADER                                       │
│  ├─ Sample textures                                         │
│  ├─ Calculate lighting                                      │
│  └─ Output final color                                      │
│       ↓                                                      │
│  OUTPUT (Framebuffer)                                        │
└─────────────────────────────────────────────────────────────┘
┌─────────────────────────────────────────────────────────────┐
│                    RENDERING PIPELINE                        │
├─────────────────────────────────────────────────────────────┤
│  CPU (游戏逻辑)                                            │
│       ↓                                                      │
│  VERTEX SHADER                                               │
│  ├─ 将顶点转换到裁剪空间                        │
│  ├─ 计算法线、切线                             │
│  └─ 向片段着色器传递数据                            │
│       ↓                                                      │
│  RASTERIZATION (固定功能管线)                              │
│  ├─ 三角形设置                                          │
│  ├─ 像素覆盖                                          │
│  └─ 插值                                           │
│       ↓                                                      │
│  FRAGMENT/PIXEL SHADER                                       │
│  ├─ 采样纹理                                         │
│  ├─ 计算光照                                      │
│  └─ 输出最终颜色                                      │
│       ↓                                                      │
│  OUTPUT (帧缓冲)                                        │
└─────────────────────────────────────────────────────────────┘

Basic Shader Structure

基础Shader结构

hlsl
// ✅ Production-Ready: Basic Surface Shader (Unity HLSL)
Shader "Custom/BasicSurface"
{
    Properties
    {
        _MainTex ("Albedo", 2D) = "white" {}
        _Color ("Color Tint", Color) = (1,1,1,1)
        _Metallic ("Metallic", Range(0,1)) = 0.0
        _Smoothness ("Smoothness", Range(0,1)) = 0.5
        _NormalMap ("Normal Map", 2D) = "bump" {}
        _NormalStrength ("Normal Strength", Range(0,2)) = 1.0
    }

    SubShader
    {
        Tags { "RenderType"="Opaque" "Queue"="Geometry" }
        LOD 200

        CGPROGRAM
        #pragma surface surf Standard fullforwardshadows
        #pragma target 3.0

        sampler2D _MainTex;
        sampler2D _NormalMap;
        half4 _Color;
        half _Metallic;
        half _Smoothness;
        half _NormalStrength;

        struct Input
        {
            float2 uv_MainTex;
            float2 uv_NormalMap;
        };

        void surf(Input IN, inout SurfaceOutputStandard o)
        {
            // Albedo
            half4 c = tex2D(_MainTex, IN.uv_MainTex) * _Color;
            o.Albedo = c.rgb;

            // Normal mapping
            half3 normal = UnpackNormal(tex2D(_NormalMap, IN.uv_NormalMap));
            normal.xy *= _NormalStrength;
            o.Normal = normalize(normal);

            // PBR properties
            o.Metallic = _Metallic;
            o.Smoothness = _Smoothness;
            o.Alpha = c.a;
        }
        ENDCG
    }
    FallBack "Diffuse"
}
hlsl
// ✅ 生产可用:基础表面Shader(Unity HLSL)
Shader "Custom/BasicSurface"
{
    Properties
    {
        _MainTex ("Albedo", 2D) = "white" {}
        _Color ("颜色色调", Color) = (1,1,1,1)
        _Metallic ("金属度", Range(0,1)) = 0.0
        _Smoothness ("光滑度", Range(0,1)) = 0.5
        _NormalMap ("法线贴图", 2D) = "bump" {}
        _NormalStrength ("法线强度", Range(0,2)) = 1.0
    }

    SubShader
    {
        Tags { "RenderType"="Opaque" "Queue"="Geometry" }
        LOD 200

        CGPROGRAM
        #pragma surface surf Standard fullforwardshadows
        #pragma target 3.0

        sampler2D _MainTex;
        sampler2D _NormalMap;
        half4 _Color;
        half _Metallic;
        half _Smoothness;
        half _NormalStrength;

        struct Input
        {
            float2 uv_MainTex;
            float2 uv_NormalMap;
        };

        void surf(Input IN, inout SurfaceOutputStandard o)
        {
            // 反照率
            half4 c = tex2D(_MainTex, IN.uv_MainTex) * _Color;
            o.Albedo = c.rgb;

            // 法线贴图
            half3 normal = UnpackNormal(tex2D(_NormalMap, IN.uv_NormalMap));
            normal.xy *= _NormalStrength;
            o.Normal = normalize(normal);

            // PBR属性
            o.Metallic = _Metallic;
            o.Smoothness = _Smoothness;
            o.Alpha = c.a;
        }
        ENDCG
    }
    FallBack "Diffuse"
}

Advanced Effects

高级效果

Toon/Cel Shading

卡通/赛璐璐着色

hlsl
// ✅ Production-Ready: Toon Shader
Shader "Custom/Toon"
{
    Properties
    {
        _MainTex ("Texture", 2D) = "white" {}
        _Color ("Color", Color) = (1,1,1,1)
        _RampTex ("Ramp Texture", 2D) = "white" {}
        _OutlineColor ("Outline Color", Color) = (0,0,0,1)
        _OutlineWidth ("Outline Width", Range(0, 0.1)) = 0.02
    }

    SubShader
    {
        Tags { "RenderType"="Opaque" }

        // Outline Pass
        Pass
        {
            Cull Front

            CGPROGRAM
            #pragma vertex vert
            #pragma fragment frag

            struct appdata
            {
                float4 vertex : POSITION;
                float3 normal : NORMAL;
            };

            struct v2f
            {
                float4 pos : SV_POSITION;
            };

            float _OutlineWidth;
            float4 _OutlineColor;

            v2f vert(appdata v)
            {
                v2f o;
                // Expand vertices along normals
                float3 scaled = v.vertex.xyz + v.normal * _OutlineWidth;
                o.pos = UnityObjectToClipPos(float4(scaled, 1.0));
                return o;
            }

            half4 frag(v2f i) : SV_Target
            {
                return _OutlineColor;
            }
            ENDCG
        }

        // Main Toon Pass
        Pass
        {
            CGPROGRAM
            #pragma vertex vert
            #pragma fragment frag

            sampler2D _MainTex;
            sampler2D _RampTex;
            float4 _Color;

            struct appdata
            {
                float4 vertex : POSITION;
                float3 normal : NORMAL;
                float2 uv : TEXCOORD0;
            };

            struct v2f
            {
                float4 pos : SV_POSITION;
                float2 uv : TEXCOORD0;
                float3 worldNormal : TEXCOORD1;
            };

            v2f vert(appdata v)
            {
                v2f o;
                o.pos = UnityObjectToClipPos(v.vertex);
                o.uv = v.uv;
                o.worldNormal = UnityObjectToWorldNormal(v.normal);
                return o;
            }

            half4 frag(v2f i) : SV_Target
            {
                // Sample albedo
                half4 col = tex2D(_MainTex, i.uv) * _Color;

                // Calculate diffuse with ramp
                float3 lightDir = normalize(_WorldSpaceLightPos0.xyz);
                float NdotL = dot(i.worldNormal, lightDir) * 0.5 + 0.5;
                float3 ramp = tex2D(_RampTex, float2(NdotL, 0.5)).rgb;

                col.rgb *= ramp;
                return col;
            }
            ENDCG
        }
    }
}
hlsl
// ✅ 生产可用:卡通Shader
Shader "Custom/Toon"
{
    Properties
    {
        _MainTex ("纹理", 2D) = "white" {}
        _Color ("颜色", Color) = (1,1,1,1)
        _RampTex ("渐变纹理", 2D) = "white" {}
        _OutlineColor ("描边颜色", Color) = (0,0,0,1)
        _OutlineWidth ("描边宽度", Range(0, 0.1)) = 0.02
    }

    SubShader
    {
        Tags { "RenderType"="Opaque" }

        // 描边通道
        Pass
        {
            Cull Front

            CGPROGRAM
            #pragma vertex vert
            #pragma fragment frag

            struct appdata
            {
                float4 vertex : POSITION;
                float3 normal : NORMAL;
            };

            struct v2f
            {
                float4 pos : SV_POSITION;
            };

            float _OutlineWidth;
            float4 _OutlineColor;

            v2f vert(appdata v)
            {
                v2f o;
                // 沿法线方向扩展顶点
                float3 scaled = v.vertex.xyz + v.normal * _OutlineWidth;
                o.pos = UnityObjectToClipPos(float4(scaled, 1.0));
                return o;
            }

            half4 frag(v2f i) : SV_Target
            {
                return _OutlineColor;
            }
            ENDCG
        }

        // 主卡通通道
        Pass
        {
            CGPROGRAM
            #pragma vertex vert
            #pragma fragment frag

            sampler2D _MainTex;
            sampler2D _RampTex;
            float4 _Color;

            struct appdata
            {
                float4 vertex : POSITION;
                float3 normal : NORMAL;
                float2 uv : TEXCOORD0;
            };

            struct v2f
            {
                float4 pos : SV_POSITION;
                float2 uv : TEXCOORD0;
                float3 worldNormal : TEXCOORD1;
            };

            v2f vert(appdata v)
            {
                v2f o;
                o.pos = UnityObjectToClipPos(v.vertex);
                o.uv = v.uv;
                o.worldNormal = UnityObjectToWorldNormal(v.normal);
                return o;
            }

            half4 frag(v2f i) : SV_Target
            {
                // 采样反照率
                half4 col = tex2D(_MainTex, i.uv) * _Color;

                // 使用渐变纹理计算漫反射
                float3 lightDir = normalize(_WorldSpaceLightPos0.xyz);
                float NdotL = dot(i.worldNormal, lightDir) * 0.5 + 0.5;
                float3 ramp = tex2D(_RampTex, float2(NdotL, 0.5)).rgb;

                col.rgb *= ramp;
                return col;
            }
            ENDCG
        }
    }
}

Dissolve Effect

溶解效果

hlsl
// ✅ Production-Ready: Dissolve Shader
Shader "Custom/Dissolve"
{
    Properties
    {
        _MainTex ("Texture", 2D) = "white" {}
        _NoiseTex ("Noise Texture", 2D) = "white" {}
        _DissolveAmount ("Dissolve Amount", Range(0, 1)) = 0
        _EdgeColor ("Edge Color", Color) = (1, 0.5, 0, 1)
        _EdgeWidth ("Edge Width", Range(0, 0.2)) = 0.05
    }

    SubShader
    {
        Tags { "RenderType"="Opaque" }

        Pass
        {
            CGPROGRAM
            #pragma vertex vert
            #pragma fragment frag

            sampler2D _MainTex;
            sampler2D _NoiseTex;
            float _DissolveAmount;
            float4 _EdgeColor;
            float _EdgeWidth;

            struct v2f
            {
                float4 pos : SV_POSITION;
                float2 uv : TEXCOORD0;
            };

            v2f vert(appdata_base v)
            {
                v2f o;
                o.pos = UnityObjectToClipPos(v.vertex);
                o.uv = v.texcoord;
                return o;
            }

            half4 frag(v2f i) : SV_Target
            {
                half4 col = tex2D(_MainTex, i.uv);
                float noise = tex2D(_NoiseTex, i.uv).r;

                // Discard dissolved pixels
                clip(noise - _DissolveAmount);

                // Add edge glow
                float edge = 1 - smoothstep(0, _EdgeWidth, noise - _DissolveAmount);
                col.rgb = lerp(col.rgb, _EdgeColor.rgb, edge);

                return col;
            }
            ENDCG
        }
    }
}
hlsl
// ✅ 生产可用:溶解Shader
Shader "Custom/Dissolve"
{
    Properties
    {
        _MainTex ("纹理", 2D) = "white" {}
        _NoiseTex ("噪声纹理", 2D) = "white" {}
        _DissolveAmount ("溶解程度", Range(0, 1)) = 0
        _EdgeColor ("边缘颜色", Color) = (1, 0.5, 0, 1)
        _EdgeWidth ("边缘宽度", Range(0, 0.2)) = 0.05
    }

    SubShader
    {
        Tags { "RenderType"="Opaque" }

        Pass
        {
            CGPROGRAM
            #pragma vertex vert
            #pragma fragment frag

            sampler2D _MainTex;
            sampler2D _NoiseTex;
            float _DissolveAmount;
            float4 _EdgeColor;
            float _EdgeWidth;

            struct v2f
            {
                float4 pos : SV_POSITION;
                float2 uv : TEXCOORD0;
            };

            v2f vert(appdata_base v)
            {
                v2f o;
                o.pos = UnityObjectToClipPos(v.vertex);
                o.uv = v.texcoord;
                return o;
            }

            half4 frag(v2f i) : SV_Target
            {
                half4 col = tex2D(_MainTex, i.uv);
                float noise = tex2D(_NoiseTex, i.uv).r;

                // 丢弃已溶解的像素
                clip(noise - _DissolveAmount);

                // 添加边缘发光
                float edge = 1 - smoothstep(0, _EdgeWidth, noise - _DissolveAmount);
                col.rgb = lerp(col.rgb, _EdgeColor.rgb, edge);

                return col;
            }
            ENDCG
        }
    }
}

Post-Processing Effects

后处理效果

hlsl
// ✅ Production-Ready: Screen-Space Vignette
Shader "PostProcess/Vignette"
{
    Properties
    {
        _MainTex ("Texture", 2D) = "white" {}
        _Intensity ("Intensity", Range(0, 1)) = 0.5
        _Smoothness ("Smoothness", Range(0.01, 1)) = 0.5
    }

    SubShader
    {
        Pass
        {
            CGPROGRAM
            #pragma vertex vert_img
            #pragma fragment frag

            sampler2D _MainTex;
            float _Intensity;
            float _Smoothness;

            half4 frag(v2f_img i) : SV_Target
            {
                half4 col = tex2D(_MainTex, i.uv);

                // Calculate vignette
                float2 center = i.uv - 0.5;
                float dist = length(center);
                float vignette = smoothstep(0.5, 0.5 - _Smoothness, dist);
                vignette = lerp(1, vignette, _Intensity);

                col.rgb *= vignette;
                return col;
            }
            ENDCG
        }
    }
}
hlsl
// ✅ 生产可用:屏幕空间暗角
Shader "PostProcess/Vignette"
{
    Properties
    {
        _MainTex ("纹理", 2D) = "white" {}
        _Intensity ("强度", Range(0, 1)) = 0.5
        _Smoothness ("平滑度", Range(0.01, 1)) = 0.5
    }

    SubShader
    {
        Pass
        {
            CGPROGRAM
            #pragma vertex vert_img
            #pragma fragment frag

            sampler2D _MainTex;
            float _Intensity;
            float _Smoothness;

            half4 frag(v2f_img i) : SV_Target
            {
                half4 col = tex2D(_MainTex, i.uv);

                // 计算暗角
                float2 center = i.uv - 0.5;
                float dist = length(center);
                float vignette = smoothstep(0.5, 0.5 - _Smoothness, dist);
                vignette = lerp(1, vignette, _Intensity);

                col.rgb *= vignette;
                return col;
            }
            ENDCG
        }
    }
}

Shader Optimization

Shader优化

OPTIMIZATION TECHNIQUES:
┌─────────────────────────────────────────────────────────────┐
│  PRECISION:                                                  │
│  • Use half instead of float where possible                 │
│  • Mobile: Always prefer half/fixed                         │
│  • PC: float for positions, half for colors                │
├─────────────────────────────────────────────────────────────┤
│  TEXTURE SAMPLING:                                           │
│  • Minimize texture samples                                 │
│  • Use texture atlases                                      │
│  • Avoid dependent texture reads                            │
│  • Use lower mipmap for distant objects                     │
├─────────────────────────────────────────────────────────────┤
│  MATH OPERATIONS:                                            │
│  • Replace div with mul (x/2 → x*0.5)                       │
│  • Use MAD operations (a*b+c)                               │
│  • Avoid branching in fragment shaders                      │
│  • Pre-compute constants                                    │
├─────────────────────────────────────────────────────────────┤
│  VARIANTS:                                                   │
│  • Minimize shader keywords                                 │
│  • Use multi_compile_local                                  │
│  • Strip unused variants                                    │
└─────────────────────────────────────────────────────────────┘

COST COMPARISON (Relative):
┌─────────────────────────────────────────────────────────────┐
│  Operation          │ Cost  │ Notes                         │
├─────────────────────┼───────┼───────────────────────────────┤
│  Add/Multiply       │ 1x    │ Baseline                      │
│  Divide             │ 4x    │ Avoid in loops                │
│  Sqrt               │ 4x    │ Use rsqrt when possible       │
│  Sin/Cos            │ 8x    │ Use lookup tables on mobile   │
│  Texture Sample     │ 4-8x  │ Varies by hardware            │
│  Pow                │ 8x    │ Use exp2(x*log2(y))          │
│  Normalize          │ 4x    │ Pre-normalize in vertex      │
└─────────────────────┴───────┴───────────────────────────────┘
优化技巧:
┌─────────────────────────────────────────────────────────────┐
│  精度优化:                                                  │
│  • 尽可能使用half而非float                 │
│  • 移动端:优先使用half/fixed                         │
│  • PC端:位置使用float,颜色使用half                │
├─────────────────────────────────────────────────────────────┤
│  纹理采样优化:                                           │
│  • 减少纹理采样次数                                 │
│  • 使用纹理图集                                      │
│  • 避免依赖纹理读取                            │
│  • 远处物体使用低等级Mipmap                     │
├─────────────────────────────────────────────────────────────┤
│  数学运算优化:                                            │
│  • 用乘法替代除法(x/2 → x*0.5)                       │
│  • 使用MAD运算(a*b+c)                               │
│ • 避免在片段着色器中使用分支                      │
│  • 预计算常量                                    │
├─────────────────────────────────────────────────────────────┤
│  变体优化:                                                   │
│  • 减少Shader关键字                                 │
│  • 使用multi_compile_local                                  │
│  • 移除未使用的变体                                    │
└─────────────────────────────────────────────────────────────┘

相对成本对比:
┌─────────────────────────────────────────────────────────────┐
│  操作          │ 成本  │ 说明                         │
├─────────────────────┼───────┼───────────────────────────────┤
│  加法/乘法       │ 1x    │ 基准值                      │
│  除法             │ 4x    │ 避免在循环中使用                │
│  平方根               │ 4x    │ 尽可能使用rsqrt       │
│  正弦/余弦            │ 8x    │ 移动端使用查找表   │
│  纹理采样     │ 4-8x  │ 因硬件而异            │
│  幂运算                │ 8x    │ 使用exp2(x*log2(y))          │
│  归一化          │ 4x    │ 在顶点着色器中预归一化      │
└─────────────────────┴───────┴───────────────────────────────┘

🔧 Troubleshooting

🔧 故障排除

┌─────────────────────────────────────────────────────────────┐
│ PROBLEM: Shader not compiling                               │
├─────────────────────────────────────────────────────────────┤
│ SOLUTIONS:                                                   │
│ → Check for syntax errors (missing semicolons)              │
│ → Verify all variables are declared                         │
│ → Check target platform compatibility                       │
│ → Look for mismatched semantics                             │
└─────────────────────────────────────────────────────────────┘

┌─────────────────────────────────────────────────────────────┐
│ PROBLEM: Pink/magenta material                              │
├─────────────────────────────────────────────────────────────┤
│ SOLUTIONS:                                                   │
│ → Shader failed to compile - check console                  │
│ → Missing shader on target platform                         │
│ → Add fallback shader                                       │
│ → Check render pipeline compatibility                       │
└─────────────────────────────────────────────────────────────┘

┌─────────────────────────────────────────────────────────────┐
│ PROBLEM: Shader too slow                                    │
├─────────────────────────────────────────────────────────────┤
│ SOLUTIONS:                                                   │
│ → Profile with GPU debugger (RenderDoc)                     │
│ → Reduce texture samples                                    │
│ → Use lower precision                                       │
│ → Simplify math operations                                  │
│ → Move calculations to vertex shader                        │
└─────────────────────────────────────────────────────────────┘

┌─────────────────────────────────────────────────────────────┐
│ PROBLEM: Too many shader variants                           │
├─────────────────────────────────────────────────────────────┤
│ SOLUTIONS:                                                   │
│ → Use shader_feature instead of multi_compile               │
│ → Strip unused variants in build settings                   │
│ → Combine keywords where possible                           │
│ → Use material property blocks                              │
└─────────────────────────────────────────────────────────────┘
┌─────────────────────────────────────────────────────────────┐
│ 问题:Shader编译失败                               │
├─────────────────────────────────────────────────────────────┤
│ 解决方案:                                                   │
│ → 检查语法错误(缺失分号)              │
│ → 验证所有变量已声明                         │
│ → 检查目标平台兼容性                       │
│ → 查找不匹配的语义                             │
└─────────────────────────────────────────────────────────────┘

┌─────────────────────────────────────────────────────────────┐
│ 问题:材质显示为粉/品红色                              │
├─────────────────────────────────────────────────────────────┤
│ 解决方案:                                                   │
│ → Shader编译失败 - 检查控制台                  │
│ → 目标平台缺失对应的Shader                         │
│ → 添加回退Shader                                       │
│ → 检查渲染管线兼容性                       │
└─────────────────────────────────────────────────────────────┘

┌─────────────────────────────────────────────────────────────┐
│ 问题:Shader运行过慢                                    │
├─────────────────────────────────────────────────────────────┤
│ 解决方案:                                                   │
│ → 使用GPU调试器分析性能(RenderDoc)                     │
│ → 减少纹理采样次数                                    │
│ → 使用更低精度                                       │
│ → 简化数学运算                                  │
│ → 将计算转移到顶点着色器                        │
└─────────────────────────────────────────────────────────────┘

┌─────────────────────────────────────────────────────────────┐
│ 问题:Shader变体过多                           │
├─────────────────────────────────────────────────────────────┤
│ 解决方案:                                                   │
│ → 使用shader_feature替代multi_compile               │
│ → 在构建设置中移除未使用的变体                   │
│ → 尽可能合并关键字                           │
│ → 使用材质属性块                              │
└─────────────────────────────────────────────────────────────┘

Shader Languages by Engine

各引擎对应的Shader语言

EngineLanguageNotes
Unity URP/HDRPHLSL + ShaderGraphVisual + code
Unity Built-inCG/HLSLLegacy surface shaders
UnrealHLSL + Material EditorNode-based preferred
GodotGodot Shading LanguageSimilar to GLSL
OpenGLGLSLCross-platform
DirectXHLSLWindows/Xbox
VulkanSPIR-V (from GLSL)Low-level

Use this skill: When creating custom visuals, optimizing rendering, or implementing advanced effects.
引擎语言说明
Unity URP/HDRPHLSL + ShaderGraph可视化+代码
Unity 内置管线CG/HLSL传统表面Shader
UnrealHLSL + 材质编辑器优先使用节点式
GodotGodot Shading Language类似GLSL
OpenGLGLSL跨平台
DirectXHLSLWindows/Xbox
VulkanSPIR-V(基于GLSL)底层

使用场景:创建自定义视觉效果、优化渲染性能或实现高级特效时。