mirrors
/
hyperrogue
mirror of https://github.com/zenorogue/hyperrogue.git
1
0
Fork 0
Code Issues Releases Wiki Activity

refactored bt coordinate functions

This commit is contained in:
Zeno Rogue 2021-10-07 12:41:44 +02:00
parent 4ff08f3f3e
commit 8d0059a760
1 changed files with 10 additions and 16 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

26
binary-tiling.cpp
View File

@ -809,12 +809,14 @@ EX namespace bt {
}
#endif
EX ld xy_mul() { return vid.binary_width * log(2) / 2; }
EX transmatrix parabolic(ld u) {
return parabolic1(u * vid.binary_width / log(2) / 2);
return parabolic1(u * xy_mul());
}
EX transmatrix parabolic3(ld y, ld z) {
ld co = vid.binary_width / log(2) / 4;
ld co = xy_mul();
return hr::parabolic13(y * co, z * co);
}
@ -827,30 +829,22 @@ EX namespace bt {
return log(2) + log(-h[0]);
}
/** you probably want minkowski_to_bt */
EX hyperpoint deparabolic3(hyperpoint h) {
h /= (1 + h[3]);
hyperpoint one = point3(1,0,0);
h -= one;
h /= sqhypot_d(3, h);
h[0] += .5;
ld co = vid.binary_width / log(2) / 8;
return point3(log(2) + log(-h[0]), h[1] / co, h[2] / co);
}
/** \brief convert BT coordinates to Minkowski coordinates
in the BT coordinates, h[2] is vertical; the center of the horosphere in Klein model is (1,0,0)
*/
EX hyperpoint bt_to_minkowski(hyperpoint h) {
ld yy = log(2) / 2;
return parabolic3(h[0], h[1]) * xpush0(yy*h[2]);
ld co = xy_mul();
return hr::parabolic13(h[0] * co, h[1] * co) * xpush0(yy*h[2]);
}
/** \brief inverse of bt_to_minkowski */
EX hyperpoint minkowski_to_bt(hyperpoint h) {
h = bt::deparabolic3(h);
h = point3(h[1], h[2], h[0] / (log(2)/2));
h = deparabolic13(h);
ld co = xy_mul();
ld yy = log(2) / 2;
h = point31(h[1] / co, h[2] / co, h[0] / yy);
return h;
}