Replace the C++ implementation with the Rust port

The Rust port (formerly gipfel-rs) is now the official successor to the
FLTK/GSL C++ code base. This squashes the port into a single commit and
removes the C++ sources (they remain in the git history below).

Layout:
  crates/gipfel-core  headless core: hills, panorama geometry, projections
                      (maxima-generated derivatives), pure-Rust LM fit,
                      gipfel: JPEG comment + EXIF I/O, profiles, stitching
  crates/gipfel-cli   command-line tools (export, info, stitch, profiles)
  crates/gipfel-app   Cosmic DE (libcosmic) GUI, binary name `gipfel`
  codegen/            maxima scripts + regen.sh for the projection code
  tests/              golden files + C++ reference harnesses (historical)

The original README is kept for now; it will be updated to describe the
Rust build. gipfel.dat, AUTHORS, ChangeLog and NEWS are unchanged.

1 files changed, 83 insertions, 0 deletions

diff --git a/tests/harness/fitdump.cxx b/tests/harness/fitdump.cxx
new file mode 100644
index 0000000..8ef392c
--- /dev/null
+++ b/tests/harness/fitdump.cxx
@@ -0,0 +1,83 @@
+// Golden dump: full fit through the original C++ Panorama + GSL solver.
+// Usage: fitdump <gipfel.dat> <projection 0|1>
+#include <stdio.h>
+#include <math.h>
+#include <stdlib.h>
+
+#include "Panorama.H"
+#include "Hill.H"
+#include "ProjectionRectilinear.H"
+#include "ProjectionCylindrical.H"
+
+int main(int argc, char **argv) {
+	if (argc < 3) {
+		fprintf(stderr, "usage: fitdump <gipfel.dat> <projection>\n");
+		return 1;
+	}
+
+	Panorama pan;
+	if (pan.load_data(argv[1])) {
+		fprintf(stderr, "load failed\n");
+		return 1;
+	}
+	pan.set_projection((ProjectionLSQ::Projection_t) atoi(argv[2]));
+
+	pan.set_view_lat(47.36);
+	pan.set_view_long(11.15);
+	pan.set_view_height(2100.0);
+
+	// ground truth
+	pan.set_center_angle(20.0);
+	pan.set_nick_angle(0.0);
+	pan.set_tilt_angle(1.0);
+	pan.set_scale(3000.0);
+
+	// observed positions = projection of first 6 visible hills (snapshotted
+	// as copies so the perturbation below does not overwrite them)
+	Hills *vis = pan.get_visible_mountains();
+	Hills known;
+	int n = vis->get_num() < 6 ? vis->get_num() : 6;
+	for (int i = 0; i < n; i++) {
+		Hill *c = new Hill(*vis->get(i));
+		// NOTE: Hill's copy ctor in the original does not copy a_nick
+		// (uninitialized garbage -> LSQR stagnates). The real app always
+		// fits hills living in the main list where a_nick is set, so set it
+		// here to reproduce the real-app behavior.
+		c->a_nick = vis->get(i)->a_nick;
+		known.add(c);
+	}
+
+	// perturb the initial guess
+	pan.set_center_angle(pan.get_center_angle() + 0.5);
+	pan.set_nick_angle(0.3);
+	pan.set_tilt_angle(0.5);
+	pan.set_scale(2800.0);
+
+	int ret = pan.comp_params(&known);
+
+	ViewParams *p = &pan.parms;
+	printf("ret %d\n", ret);
+	printf("a_center %.17g\n", p->a_center);
+	printf("a_nick %.17g\n", p->a_nick);
+	printf("a_tilt %.17g\n", p->a_tilt);
+	printf("scale %.17g\n", p->scale);
+	printf("k0 %.17g\n", p->k0);
+	printf("k1 %.17g\n", p->k1);
+	printf("x0 %.17g\n", p->x0);
+
+	// final image coordinates of the known hills (bypass visibility check)
+	for (int i = 0; i < known.get_num(); i++) {
+		Hill *m = known.get(i);
+		double x = NAN, y = NAN;
+		if (atoi(argv[2]) == 1) {
+			ProjectionCylindrical pc;
+			pc.get_coordinates(m->alph, m->a_nick, &pan.parms, &x, &y);
+		} else {
+			ProjectionRectilinear pr;
+			pr.get_coordinates(m->alph, m->a_nick, &pan.parms, &x, &y);
+		}
+		printf("hill %d %.17g %.17g\n", i, x, y);
+	}
+
+	return 0;
+}