code wiki / _hdl_build / nx_geo_distance_gate.nx
`nx_geo_distance_gate.nx` source

1// nx_geo_distance_gate.nx -- GATE for GEO-003 equirectangular distance. Proves on KATs:
2//   1deg latitude  ~= 111195 m   (the meters-per-degree anchor)
3//   1deg longitude at equator ~= 111195 m
4//   1deg longitude at 60N ~= half of that (cos(60)=0.5 -> longitude-compression in METERS)
5//   same point -> 0
6//   ratio: (1deg lon equator) ~= 2 * (1deg lon at 60N)  -> the cos law holds in the distance, too
7// Tolerances are generous (equirectangular + fixed-point + isqrt rounding); the point is the
8// capability + the cos compression, not sub-meter accuracy.
9//
10// Evidence -> knowledge/status/geo_distance.log (GEODISTGATE authored=organ ... verdict=GREEN).
11// license_tier: ORIGINAL
12import "nx_geo_distance.nx"
13import "nx_syscalls.nx"
14import "nx_gate_verdict.nx"
15
16const GD_LOG: *u8 = "knowledge/status/geo_distance.log"
17
18func gd_w(fd: i64, s: *u8) -> i64 { var n: i64 = 0; while s[n] != (0 as u8) { n = n + 1 } sys_write(fd, s, n); return 0 }
19func gd_wn(fd: i64, v: i64) -> i64 { let bb: *u8 = sys_mmap(28); var m: i64=v; if m<0 {m=0-m; sys_write(fd,"-" as *u8,1)}; let t: *u8 = sys_mmap(28); var k: i64=0; if m==0 {t[0]=48;k=1}; while m>0 {t[k]=(48+(m%10)) as u8; m=m/10; k=k+1}; var i: i64=0; while i<k {bb[i]=t[k-1-i]; i=i+1}; sys_write(fd, bb, k); return 0 }
20
21// 1 if |a-b| <= tol
22func gd_near(a: i64, b: i64, tol: i64) -> i64 {
23    var d: i64 = a - b
24    if d < 0 { d = 0 - d }
25    if d <= tol { return 1 }
26    return 0
27}
28
29func gd_emit(fd: i64, dlat: i64, dlonEq: i64, dlon60: i64, dzero: i64, ok: i64) -> i64 {
30    gd_w(fd, "GEODISTGATE authored=organ method=equirectangular-fixedpoint deg_lat_m=" as *u8); gd_wn(fd, dlat)
31    gd_w(fd, " deg_lon_equator_m=" as *u8); gd_wn(fd, dlonEq)
32    gd_w(fd, " deg_lon_60N_m=" as *u8); gd_wn(fd, dlon60)
33    gd_w(fd, " same_point_m=" as *u8); gd_wn(fd, dzero)
34    if ok == 1 { gd_w(fd, " verdict=GREEN\n" as *u8) } else { gd_w(fd, " verdict=RED\n" as *u8) }
35    return 0
36}
37
38func main() -> i64 {
39    let dlat:   i64 = geo_distance_m(0, 0, 1000000, 0)            // 1 deg north @ equator
40    let dlonEq: i64 = geo_distance_m(0, 0, 0, 1000000)            // 1 deg east @ equator
41    let dlon60: i64 = geo_distance_m(60000000, 0, 60000000, 1000000)  // 1 deg east @ 60N
42    let dzero:  i64 = geo_distance_m(45000000, 45000000, 45000000, 45000000)  // same point
43
44    var ok: i64 = 1
45    if gd_near(dlat, 111195, 300) != 1 { ok = 0 }
46    if gd_near(dlonEq, 111195, 600) != 1 { ok = 0 }
47    if gd_near(dlon60, 55600, 800) != 1 { ok = 0 }       // ~half (cos 60 = 0.5)
48    if dzero != 0 { ok = 0 }
49    // the cos law in meters: 1deg lon at equator ~= 2 * (1deg lon at 60N)
50    if gd_near(dlonEq, dlon60 * 2, 1500) != 1 { ok = 0 }
51
52    gd_emit(1, dlat, dlonEq, dlon60, dzero, ok)
53    let lf: i64 = sys_openat_append(GD_LOG, 420)
54    if lf >= 0 { gd_emit(lf, dlat, dlonEq, dlon60, dzero, ok); sys_close(lf) }
55
56    // MIGRATED onto nx_gate_verdict by nx_gate_dry_apply (D001, minimal form): every check
57    // row above is untouched, so the PASS/FAIL vector cannot change; only the hand-rolled
58    // verdict emission is replaced by the ONE shared base class. Proven by nx_gate_migrate verify.
59    let ctr__dry: *i64 = gv_ctr()
60    ctr__dry[0] = ok
61    ctr__dry[1] = 1
62    let rc__dry: i64 = gv_verdict("GEO-DISTANCE-GATE" as *u8, ctr__dry, "teeth unchanged; verdict emission migrated onto the shared base class" as *u8)
63    sys_exit(rc__dry)
64    return rc__dry
65}
nx_geo_distance_gate.nx source

`nx_geo_distance_gate.nx` source
