hyperrogue/generators/macbeath.cpp

133 lines
2.9 KiB
C++

// Fricke-Macbeath Surface generator
// Copyright (C) 2018 Zeno Rogue, see 'hyper.cpp' for details
#include <stdio.h>
#include <vector>
#include <array>
#include <map>
using namespace std;
int isize(const auto x) { return x.size(); }
int mul(int a, int b) {
int p = 0;
for(int i=0; i<3; i++) if((a>>i)&1)
for(int j=0; j<3; j++) if((b>>j)&1)
p ^= (1<<(i+j));
for(int z=4; z>=0; z--)
if(p&(8<<z)) p ^= (11<<z);
return p;
}
int multable[8][8];
int elements = 0;
vector<array<int, 4>> psl_elements;
int multable_psl[504][504];
map<array<int, 4>, int> back;
int mpow(int a, int n) {
int z = a;
while(n > 1) z = multable_psl[a][z], n--;
return z;
}
int inset[504];
int main() {
for(int a=0; a<8; a++) {
for(int b=0; b<8; b++) printf("%d ", mul(a, b));
printf("\n");
}
for(int a=0; a<8; a++)
for(int b=0; b<8; b++)
multable[a][b] = mul(a, b);
for(int a=0; a<8; a++)
for(int b=0; b<8; b++)
for(int c=0; c<8; c++)
for(int d=0; d<8; d++)
if((multable[a][d] ^ multable[b][c]) == 1) {
array<int, 4> arr = { a, b, c, d};
psl_elements.emplace_back(arr);
}
printf("elements = %d\n", isize(psl_elements));
for(int a=0; a<504; a++) back[psl_elements[a]] = a;
for(int a=0; a<504; a++)
for(int b=0; b<504; b++) {
auto pa = psl_elements[a];
auto pb = psl_elements[b];
array<int, 4> pc;
for(int s=0; s<4; s++) {
int s0 = s&2;
int s1 = s&1;
pc[s] = (multable[pa[s0]][pb[s1]] ^ multable[pa[s0^1]][pb[s1^2]]);
}
multable_psl[a][b] = back[pc];
}
int id;
for(int a=0; a<504; a++)
if(multable_psl[a][a] == a) id = a;
printf("id = %d\n", id);
int xid = 0;
for(int R=0; R<504; R++)
for(int P=0; P<504; P++) {
if(multable_psl[P][P] != id) continue;
if(mpow(multable_psl[R][P], 3) != id) continue;
if(mpow(R, 7) != id) continue;
xid++;
vector<int> allels = {id};
inset[id] = xid;
for(int i=0; i<isize(allels); i++) {
for(int m: {P, R}) {
int im = allels[i];
int a = multable_psl[im][m];
// printf("%d x %d = %d\n", im, m, a);
if(inset[a] != xid) inset[a] = xid, allels.push_back(a);
}
}
printf("R = %d P = %d count = %d\n", R, P, isize(allels));
array<int, 504> cellid;
array<int, 504> bycellid;
for(int a=0; a<504; a++) cellid[a] = 0;
int ncell = 0;
for(int a=0; a<504; a++) if(cellid[a] == 0) {
int b = a;
for(int s=0; s<7; s++) cellid[b] = ncell + s, bycellid[ncell + s] = b, b = multable_psl[b][R];
ncell += 7;
}
printf("ncell = %d\n", ncell);
for(int a=0; a<72; a++) {
printf("/* %03d */ ", a);
for(int b=0; b<7; b++) {
printf("%d, ", cellid[multable_psl[bycellid[7*a+b]][P]]);
}
printf("\n");
}
return 0;
}
return 0;
}