calculate texture mipmap level in fragment shader.
shader code
float4 _MipMapColors[11];
float4 _MainTex_TexelSize;
fixed4 frag (v2f_img i) : SV_Target
{
float2 uv = i.uv * _MainTex_TexelSize.zw;
float2 dx = ddx(uv);
float2 dy = ddy(uv);
float rho = max(dot(dx, dx), dot(dy, dy));
float lambda = 0.5 * log2(rho);
int d = max(int(lambda + 0.5), 0);
return _MipMapColors[d];
}hardware mipmap level(left) vs shader mipmap level(right)
