feat: camera moves include static holds on one object; X to Y fires less often

Co-Authored-By: Claude Sonnet 5.5 <noreply@anthropic.com>

shot_camera.py

@@ -61,7 +61,10 @@ MOVES_THEN = ("Then the camera pans to {y}.", "Then the camera racks focus to {y
 MOVES_FINISH = ("Then the camera zooms out.", "Then the camera pulls back.",
                "Then the camera pulls back to a wider view.")
 COUNT_WEIGHTS = (6, 3, 1)      # one move / two / three, in a shot that gets any
-TRAVEL_SHARE = 0.5             # of one-move shots with two topics, how many travel X -> Y
+TRAVEL_SHARE = 0.25            # of one-move shots with two topics, how many travel X -> Y
+HOLD_SHARE = 0.25              # of the other one-move shots, how many stay still on one thing
+MOVES_HOLD = ("The camera holds steady on {x}.", "The camera stays still, focused on {x}.",
+              "The camera stays fixed, focused on {x}.")
 DETERMINERS = {"the", "a", "an", "this", "that", "these", "those"}
 POSSESSIVE_PRONOUNS = {"his", "her", "their", "its", "my", "your", "our"}
 
@@ -277,6 +280,10 @@ def _plan(pool, last, rng, prior=None):
         x, y = _name(topics[0]), _name(topics[-1])
         move = _pick(MOVES_TRAVEL, last, rng)
         return move.format(x=x, y=y), f"{x} -> {y}", move
+    if rng is not None and k == 1 and rng.random() < HOLD_SHARE:
+        hold = _pick(MOVES_HOLD, last, rng)              # some shots want one fixed focus
+        target = _name(best)
+        return hold.format(x=target), target, hold
     first = topics[0] if (k > 1 and topics) else best
     moves = MOVES_DETAIL if (first[2] or first[0] in PARTS) else MOVES_OTHER
     opening = _pick(moves, last, rng)

tests/test_shot_camera.py

@@ -417,3 +417,20 @@ def test_a_move_never_ends_on_a_dangling_word():
     P = HEAD + "[Shot 1] <Subject 1> touches the base, then the skin, while <Subject 2> watches."
     _out, rep = sc.add_camera_moves(P, seed=1, chance=1.0)
     assert rep[0]["move"] is None
+
+
+def test_some_shots_hold_still_on_one_object_and_pans_are_the_minority():
+    """Not every shot is a move: a static focus is part of the mix, and X -> Y is rarer than it."""
+    pytest.importorskip("spacy")
+    kinds = {"hold": 0, "pan": 0, "other": 0}
+    for seed in range(300):
+        _o, rep = sc.add_camera_moves(TWO, seed=seed)
+        m = rep[0]["move"]
+        if "holds steady" in m or "stays still" in m or "stays fixed" in m:
+            kinds["hold"] += 1
+        elif " from " in m and " to " in m and " Then" not in m:
+            kinds["pan"] += 1
+        else:
+            kinds["other"] += 1
+    assert kinds["hold"] > 20 and 0 < kinds["pan"] < kinds["other"], kinds
+    assert kinds["pan"] < 0.3 * 300, kinds