Shader-基础纹理-渐变纹理

渐变纹理

一种基于冷暖色调的着色技术，通过渐变纹理控制漫反射光照。核心部分来说用过使用halfLambert构建一个纹理坐标，用这个纹理坐标来对渐变纹理进行采样。

代码语言：javascript复制

Shader "Unlit/RampTexture"
{
    Properties{
        _Color("Color Tint",Color) = (1,1,1,1)
        _RampTex("Ramp Tex",2D) = "white"{}
        _Specular("Specular",Color) = (1,1,1,1)
        _Gloss("Gloss",Range(8.0,256)) = 20
    }
        SubShader{
        Pass{
            Tags{"LightMode" = "ForwardBase"}
            CGPROGRAM
            #pragma vertex vert
            #pragma fragment frag
            #include "Lighting.cginc"

            fixed4 _Color;
            sampler2D _RampTex;
            float4 _RampTex_ST;
            fixed4 _Specular;
            float _Gloss;

            struct a2v {
                float4 vertex : POSITION;
                float3 normal : NORMAL;
                float4 texcoord : TEXCOORD0;
            };
            struct v2f {
                float4 pos : SV_POSITION;
                float3 worldNormal : TEXCOORD0;
                float3 worldPos : TEXCOORD1;
                float2 uv : TEXCOORD2;
            };

            v2f vert(a2v v) {
                v2f o;
                o.pos = mul(UNITY_MATRIX_MVP, v.vertex);
                o.worldNormal = UnityObjectToWorldNormal(v.normal);
                o.worldPos = mul(_Object2World, v.vertex).xyz;
                o.uv = TRANSFORM_TEX(v.texcoord, _RampTex);
                return o;
            }
            fixed4 frag(v2f i): SV_Target {
                fixed3 worldNormal = normalize(i.worldNormal);
                fixed3 worldLightDir = normalize(UnityWorldSpaceLightDir(i.worldPos));
                fixed3 ambient = UNITY_LIGHTMODEL_AMBIENT.xyz;

                fixed halfLambert = 0.5 * dot(worldNormal, worldLightDir)   0.5;
                fixed3 diffuseColor = tex2D(_RampTex, fixed2(halfLambert, halfLambert)).rgb * _Color.rgb;//少了一个分号
                fixed3 diffuse = _LightColor0.rgb * diffuseColor;           

                fixed3 viewDir = normalize(UnityWorldSpaceViewDir(i.worldPos));
                fixed3 halfDir = normalize(worldLightDir   viewDir);
                fixed3 specular = _LightColor0.rgb * _Specular.rgb * pow(max(0, dot(worldNormal, halfDir)), _Gloss);
                return fixed4(specular   diffuse   ambient, 1.0);       

                }
            ENDCG
        }
    }
}

三种纹理图片对应结果

RampTexture0.PNG

RampTexture1.PNG

RampTexture2.PNG

png

0 人点赞