init

tests/test_schwarzschild.c

@@ -0,0 +1,52 @@
+#include "geodesic.h"
+
+#include <math.h>
+#include <stdio.h>
+
+int main(void) {
+  SpacetimeSource spacetime = {0};
+  MetricData metric;
+  ObserverState observer;
+  ObserverState inward_observer;
+  const GeodesicTraceConfig trace = {.coordinate_time_step = 0.1,
+                                     .max_steps = 4096,
+                                     .capture_log_alpha_p0 = 8.0};
+  int result = 1;
+  if (spacetime_create_schwarzschild_ks(&spacetime, 1.0, 256.0, 1.5) ||
+      spacetime_eval(&spacetime, 0.0, (double[]){2.0, 0.0, 0.0}, &metric) ||
+      !isfinite(metric.alpha) || !isfinite(metric.gamma[0][0]) ||
+      !isfinite(metric.K[0][0]) ||
+      observer_static_schwarzschild_ks(1.0, 30.0, &observer) ||
+      observer_inward_schwarzschild_ks(1.0, 30.0, 0.5,
+                                       &inward_observer) ||
+      fabs(inward_observer.tetrad[0][0] -
+           (2.0 / sqrt(3.0)) * (observer.tetrad[0][0] +
+                                 0.5 * observer.tetrad[1][0])) >
+          1e-12 ||
+      fabs(inward_observer.tetrad[1][1] -
+           (2.0 / sqrt(3.0)) * (0.5 * observer.tetrad[0][1] +
+                                 observer.tetrad[1][1])) >
+          1e-12 ||
+      !observer_inward_schwarzschild_ks(1.0, 30.0, 1.0,
+                                         &inward_observer))
+    goto done;
+  const RayEndpoint central = geodesic_trace_past(
+      &spacetime, &observer, (double[]){1.0, 0.0, 0.0}, &trace);
+  const RayEndpoint inside_shadow = geodesic_trace_past(
+      &spacetime, &observer, (double[]){cos(0.10), sin(0.10), 0.0}, &trace);
+  const RayEndpoint outside_shadow = geodesic_trace_past(
+      &spacetime, &observer, (double[]){cos(0.30), sin(0.30), 0.0}, &trace);
+  if (central.status != RAY_ENDPOINT_CAPTURED ||
+      inside_shadow.status != RAY_ENDPOINT_CAPTURED ||
+      outside_shadow.status != RAY_ENDPOINT_ESCAPED) {
+    fprintf(stderr,
+            "Schwarzschild KS shadow regression failed (center=%d, inside=%d, "
+            "outside=%d)\n",
+            central.status, inside_shadow.status, outside_shadow.status);
+    goto done;
+  }
+  result = 0;
+done:
+  spacetime_destroy(&spacetime);
+  return result;
+}