求求大佬帮我调一下我的柏林噪声

有效必关！

代码如下：

#include<bits/stdc++.h>
using namespace std;

const double pi = 14159265358979;
const double size = 50;

long long _hash(int x){//普通的哈希函数 
	x = (x << 2) ^ 0xb9113fce;
	x *= 0xd86a32ca;
	x = (x << 2) ^ 0xd0d8958b;
	x *= 0x1d7539e1;
	x = (x << 2) ^ 0xab63ec6c;
	x *= 0x95b08412;
	x = (x << 2) ^ 0xe7d7ae4e;
	x *= 0xd22ee12b;
	return x;
}
long long hash_(int x){
	x *= 0xd22ee12b;
	x = (x << 2) ^ 0xe7d7ae4e;
	x *= 0x95b08412;
	x = (x << 2) ^ 0xab63ec6c;
	x *= 0x1d7539e1;
	x = (x << 2) ^ 0xd0d8958b;
	x *= 0xd86a32ca;
	x = (x << 2) ^ 0xb9113fce;
	return x;
}
long long _hash_(int x){
	x *= 0xba8956ac;
	x = (x << 2) ^ 0x295ff4a6;
	x *= 0xbf351d6c;
	x = (x << 2) ^ 0xbb1ea812;
	x *= 0x3e119203;
	x = (x << 2) ^ 0x2c3bd591;
	x *= 0x114b0c94;
	x = (x << 2) ^ 0x5b126d49;
	return x;
}
double fade(double x){
	return 6.0 * pow(x,5) - 15.0 * pow(x,4) + 10.0 * pow(x,3); 
}
double perlin(int x,int y,int seed){
	int chunk_x = floor(1.0 * x / size);
	int chunk_y = floor(1.0 * y / size);
	int ul = _hash_(seed + _hash(chunk_x) + hash_(chunk_y + 1)) % 360;//根据点位置计算晶格顶点的位置，并根据此计算其梯度向量 
	int ur = _hash_(seed + _hash(chunk_x + 1) + hash_(chunk_y + 1)) % 360;//同上 
	int dl = _hash_(seed + _hash(chunk_x) + hash_(chunk_y)) % 360;//同上 
	int dr = _hash_(seed + _hash(chunk_x + 1) + hash_(chunk_y)) % 360;//同上 
	double xu = 1.0 * (x - chunk_x * size) / size;
	double yu = 1.0 * (y - chunk_y * size) / size;
	double vul = xu * cos(ul * (pi / 180)) + (1 - yu) * sin(ul * (pi / 180));//计算其偏移向量和梯度向量的点积 
	double vur = (1 - xu) * cos(ur * (pi / 180)) + (1 - yu) * sin(ur * (pi / 180));//同上 
	double vdl = xu * cos(dl * (pi / 180)) + yu * sin(dl * (pi / 180));//同上 
	double vdr = (1 - xu) * cos(dr * (pi / 180)) + yu * sin(dr * (pi / 180));//同上 
	double vu = vul + fade(xu) * (vur - vul);//利用fade函数进行平滑插值 
	double vd = vdl + fade(xu) * (vdr - vdl);//同上 
	double v = vd + fade(yu) * (vu - vd);//同上 
	return v;
}

int main(){
	int seed;
	cin>>seed;
	for(int i = -500;i < 500;i++){
		for(int j = -500;j < 500;j++){
			double x = perlin(j,i,seed);
//			cout<<x<<" ";
			if(0.8 >= x && x > 0.4){//可视化 
				cout<<"\033[31m██\033[0m";//红色 
			}else
			if(0.4 >= x && x > 0.2){
				cout<<"\033[33m██\033[0m";//黄色 
			}else
			if(0.2 >= x && x > 0){
				cout<<"\033[32m██\033[0m";//绿色 
			}else
			if(0 >= x && x > -0.2){
				cout<<"\033[36m██\033[0m";//青色 
			}else
			if(-0.2 >= x && x > -0.4){
				cout<<"\033[34m██\033[0m";//蓝色 
			}else
			if(-0.4 >= x && x > -0.6){
				cout<<"\033[35m██\033[0m";//紫色 
			}else
			if(-0.6 >= x && x > -0.8){
				cout<<"\033[37m██\033[0m";//白色 
			}else{
				cout<<"  ";//黑色 
			}
		}
		cout<<endl;
	}
}

现在的问题就是它的晶格边缘的等高线会出现一个明显的拐角，就像这个一样： 另外附上我学习柏林噪声的视频链接