Support bounded shared transverse motion and steady pinball demo

2026-10-31 13:58:19 +08:00
parent d0968e6e91
commit 33dcb422c6
8 changed files with 546 additions and 0 deletions
@@ -0,0 +1,60 @@
+"""Small serial GPU gates for shared transverse circles; no physical benchmark."""
+import json
+from pathlib import Path
+
+import numpy as np
+
+from CelerisLab import Simulation
+from CelerisLab.body.motion import MovingTables, Translation
+
+CENTRES = ((70., 79.5), (96., 94.5), (96., 64.5))
+
+
+def simulate(tmp_path, *, moving, offsets, reverse=False):
+    config = json.loads((Path(__file__).resolve().parents[2]/'research/steady_pinball/config.json').read_text())
+    config['grid'].update(nx=192, ny=160)
+    p = tmp_path/'config.json'
+    p.write_text(json.dumps(config))
+    with Simulation(str(p)) as sim:
+        envelope = Translation((0., 0., -20., 20.), .5, shared=True)
+        centres = list(reversed(CENTRES)) if reverse else list(CENTRES)
+        ids = [sim.add_body('circle', c, 10., translation=envelope if moving else None) for c in centres]
+        sim.initialize()
+        previous = 0.
+        crossings = 0.
+        for y in offsets:
+            if moving:
+                for bid in ids:
+                    sim.set_body(bid, offset=(0., float(y)), vy=float(y-previous))
+            sim.run(1)
+            if moving:
+                diag = sim.moving_diagnostics()
+                assert np.isfinite(diag).all()
+                assert np.all(diag[:, MovingTables.DIAG.index('no_donor')] == 0)
+                crossings += diag[:, MovingTables.DIAG.index('crossings')].sum()
+            previous = y
+        forces = np.array([sim.read_force(bid) for bid in ids])
+        if reverse:
+            forces = forces[::-1]
+        return sim.get_ddf(), sim.get_flags(), forces, crossings
+
+
+def test_fixed_vs_shared_hold(tmp_path):
+    fixed = simulate(tmp_path, moving=False, offsets=[0.]*32)
+    held = simulate(tmp_path, moving=True, offsets=[0.]*32)
+    assert np.array_equal(fixed[0], held[0], equal_nan=True)
+    assert np.array_equal(fixed[1], held[1])
+    # FP32 atomic force reduction order only; populations remain exactly equal.
+    np.testing.assert_allclose(fixed[2], held[2], rtol=0., atol=1e-4)
+    assert held[3] == 0
+
+
+def test_common_motion_member_order_has_no_population_effect(tmp_path):
+    offsets = np.concatenate((np.arange(.5, 20.5, .5), np.arange(19.5, -20.5, -.5),
+                              np.arange(-19.5, .5, .5)))
+    forward = simulate(tmp_path, moving=True, offsets=offsets)
+    reverse = simulate(tmp_path, moving=True, offsets=offsets, reverse=True)
+    assert forward[3] > 0 and forward[3] == reverse[3]
+    assert np.array_equal(forward[0], reverse[0], equal_nan=True)
+    assert np.array_equal(forward[1], reverse[1])
+    np.testing.assert_allclose(forward[2], reverse[2], rtol=0., atol=1e-4)