v2f vert (float4 vertex : POSITION, float3 normal : NORMAL, float4 tangent : TANGENT, float2 uv : TEXCOORD0)
{v2f o;//...half3 wNormal = UnityObjectToWorldNormal(normal);half3 wTangent = UnityObjectToWorldDir(tangent.xyz);// 计算其方向half tangentSign = tangent.w * unity_WorldTransformParams.w;// 用世界空间下的法线、切线做叉乘，得到副法线half3 wBitangent = cross(wNormal, wTangent) * tangentSign;// 得到转换矩阵o.tspace0 = half3(wTangent.x, wBitangent.x, wNormal.x);o.tspace1 = half3(wTangent.y, wBitangent.y, wNormal.y);o.tspace2 = half3(wTangent.z, wBitangent.z, wNormal.z);//...return o;
}fixed4 frag (v2f i) : SV_Target
{// 从法线贴图里采样并解码法线half3 tnormal = UnpackNormal(tex2D(_BumpMap, i.uv));// 从切线空间转换到世界空间half3 worldNormal;worldNormal.x = dot(i.tspace0, tnormal);worldNormal.y = dot(i.tspace1, tnormal);worldNormal.z = dot(i.tspace2, tnormal);//...
}

// Declares 3x3 matrix 'rotation', filled with tangent space basis
#define TANGENT_SPACE_ROTATION float3 binormal = cross( normalize(v.normal), normalize(v.tangent.xyz) ) * v.tangent.w; float3x3 rotation = float3x3( v.tangent.xyz, binormal, v.normal )

o.tangent = mul(unity_ObjectToWorld, v.tangent);
o.normal = mul(unity_ObjectToWorld, v.normal);
o.bitangent = mul(unity_ObjectToWorld, cross(v.normal, v.tangent));
//错误写法：o.bitangent = cross(o.normal, o.tangent);

o.normal = UnityObjectToWorldNormal(v.normal);
o.tangent = UnityObjectToWorldDir(v.tangent.xyz);
o.bitangent = cross(v.normal, v.tangent) * v.tangent.w * unity_WorldTransformParams.w;

fixed4 frag (v2f i) : SV_Target
{float2 uvx0 = i.uv - float2(_MainTex_TexelSize.x, 0) * 0.5;float2 uvx1 = i.uv + float2(_MainTex_TexelSize.x, 0) * 0.5;float2 uvy0 = i.uv - float2(0, _MainTex_TexelSize.y) * 0.5;float2 uvy1 = i.uv + float2(0, _MainTex_TexelSize.y) * 0.5;float3 dx = float3(_MainTex_TexelSize.x,0,(1 - tex2D(_MainTex, uvx1).r) - (1 - tex2D(_MainTex, uvx0).r));float3 dy = float3(0,_MainTex_TexelSize.y,(1 - tex2D(_MainTex, uvy1).r) - (1 - tex2D(_MainTex, uvy0).r));float3 n = cross(dx, dy);n.z *= 10;//这里可以控制法线收束于z轴的程度float3 normal = normalize(n);normal = normal * 0.5 + 0.5;  return float4(normal, 1);
}