推荐|【实现100个unity特效之25】Unity中实现二次元模型，基于光照的内置和URP管线卡通化渲染shader

最终效果

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文章目录

最终效果
默认效果
简单粗暴，使用Unlit/Texture
- 基于光照模型的卡通渲染UnityToonShader——仅支持内置渲染管线
- - 基于光照模型的二次元渲染UnityURPToonLitShaderExample——仅支持URP渲染管线
完结

默认效果

不然不做处理，我们的模型默认效果
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简单粗暴，使用Unlit/Texture

最粗暴的方式就是直接使用Unlit材质，在贴图上表现出卡通效果。
我们把材质球的shader全部改成Unlit/Texture（也就是无光照模型，直接显示贴图纹理）
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效果，当然，这过于简单了，缺点很明显，没有光照效果。

基于光照模型的卡通渲染UnityToonShader——仅支持内置渲染管线

基于光照模型的卡通渲染，在GitHub上有一个项目，地址：https://github.com/Sorumi/UnityToonShader
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ToonMultiStepsShader.shader代码我复制下来了

Shader "Toon/Basic/MultiSteps"
{
    Properties
    {
        // Colors
        _Color ("Color", Color) = (1, 1, 1, 1)
        _HColor ("Highlight Color", Color) = (0.8, 0.8, 0.8, 1.0)
        _SColor ("Shadow Color", Color) = (0.2, 0.2, 0.2, 1.0)
        
        // texture
        _MainTex ("Main Texture", 2D) = "white" { }
        
        // ramp
        _ToonSteps ("Steps of Toon", range(1, 9)) = 2
        _RampThreshold ("Ramp Threshold", Range(0.1, 1)) = 0.5
        _RampSmooth ("Ramp Smooth", Range(0, 1)) = 0.1
        
        // specular
        _SpecColor ("Specular Color", Color) = (0.5, 0.5, 0.5, 1)
        _SpecSmooth ("Specular Smooth", Range(0, 1)) = 0.1
        _Shininess ("Shininess", Range(0.001, 10)) = 0.2
        
        // rim light
        _RimColor ("Rim Color", Color) = (0.8, 0.8, 0.8, 0.6)
        _RimThreshold ("Rim Threshold", Range(0, 1)) = 0.5
        _RimSmooth ("Rim Smooth", Range(0, 1)) = 0.1
    }
    
    SubShader
    {
        Tags { "RenderType" = "Opaque" }
        
        CGPROGRAM
        
        #pragma surface surf Toon addshadow fullforwardshadows exclude_path:deferred exclude_path:prepass
        #pragma target 3.0
        
        fixed4 _Color;
        fixed4 _HColor;
        fixed4 _SColor;
        
        sampler2D _MainTex;
        
        float _RampThreshold;
        float _RampSmooth;
        float _ToonSteps;
        
        float _SpecSmooth;
        fixed _Shininess;
        
        fixed4 _RimColor;
        fixed _RimThreshold;
        float _RimSmooth;
        
        struct Input
        {
            float2 uv_MainTex;
            float3 viewDir;
        };
        
        float linearstep(float min, float max, float t)
        {
            return saturate((t - min) / (max - min));
        }
        
        inline fixed4 LightingToon(SurfaceOutput s, half3 lightDir, half3 viewDir, half atten)
        {
            half3 normalDir = normalize(s.Normal);
            half3 halfDir = normalize(lightDir + viewDir);
            
            float ndl = max(0, dot(normalDir, lightDir));
            float ndh = max(0, dot(normalDir, halfDir));
            float ndv = max(0, dot(normalDir, viewDir));
            
            // multi steps
            float diff = smoothstep(_RampThreshold - ndl, _RampThreshold + ndl, ndl);
            float interval = 1 / _ToonSteps;
            // float ramp = floor(diff * _ToonSteps) / _ToonSteps;
            float level = round(diff * _ToonSteps) / _ToonSteps;
            float ramp ;
            if (_RampSmooth == 1)
            {
                ramp = interval * linearstep(level - _RampSmooth * interval * 0.5, level + _RampSmooth * interval * 0.5, diff) + level - interval;
            }
            else
            {
                ramp = interval * smoothstep(level - _RampSmooth * interval * 0.5, level + _RampSmooth * interval * 0.5, diff) + level - interval;
            }
            ramp = max(0, ramp);
            ramp *= atten;
            
            _SColor = lerp(_HColor, _SColor, _SColor.a);
            float3 rampColor = lerp(_SColor.rgb, _HColor.rgb, ramp);
            
            // specular
            float spec = pow(ndh, s.Specular * 128.0) * s.Gloss;
            spec *= atten;
            spec = smoothstep(0.5 - _SpecSmooth * 0.5, 0.5 + _SpecSmooth * 0.5, spec);
            
            // rim
            float rim = (1.0 - ndv) * ndl;
            rim *= atten;
            rim = smoothstep(_RimThreshold - _RimSmooth * 0.5, _RimThreshold + _RimSmooth * 0.5, rim);
            
            fixed3 lightColor = _LightColor0.rgb;
            
            fixed4 color;
            fixed3 diffuse = s.Albedo * lightColor * rampColor;
            fixed3 specular = _SpecColor.rgb * lightColor * spec;
            fixed3 rimColor = _RimColor.rgb * lightColor * _RimColor.a * rim;
            
            color.rgb = diffuse + specular + rimColor;
            color.a = s.Alpha;
            return color;
        }
        
        void surf(Input IN, inout SurfaceOutput o)
        {
            fixed4 mainTex = tex2D(_MainTex, IN.uv_MainTex);
            o.Albedo = mainTex.rgb * _Color.rgb;
            
            o.Alpha = mainTex.a * _Color.a;
            
            o.Specular = _Shininess;
            o.Gloss = mainTex.a;
        }
        
        ENDCG
        
    }
    FallBack "Diffuse"
}