gameplay: compose recovered camera fallback

crates/urt-gameplay/src/bin/urt-camera-world.rs

@@ -304,6 +304,146 @@ fn run() -> Result<String, String> {
                 Err(e) => Err(format!("{e:?}")),
             }
         }
+
+        "spawn-camera" => {
+            if w.len() < 9 || w[1] > 1 || w[2] > 1024 {
+                return Err("invalid camera header".into());
+            }
+            let mut state = w[0];
+            let slot = w[1] as usize;
+            let n = w[2] as usize;
+            let fallback = urt_gameplay::transition::View {
+                origin: w[3..6].try_into().unwrap(),
+                angles: w[6..9].try_into().unwrap(),
+            };
+            let mut p = 9;
+            let mut world = vec![];
+            for _ in 0..n {
+                let v = w.get(p..p + 9).ok_or("missing world record")?;
+                p += 9;
+                let class = HashEntity {
+                    in_use: v[0] as i32,
+                    class_present: v[1] != 0,
+                    class_hash: v[2],
+                };
+                let origin = v[3..6].try_into().unwrap();
+                let angles = v[6..9].try_into().unwrap();
+                let aim = blob(&w, &mut p)?;
+                let label = blob(&w, &mut p)?;
+                world.push(WorldEntity {
+                    class,
+                    origin,
+                    angles,
+                    aim,
+                    label,
+                });
+            }
+            let blocked = w
+                .get(p..p + n)
+                .ok_or("missing telefrag flags")?
+                .iter()
+                .map(|v| *v != 0)
+                .collect::<Vec<_>>();
+            p += n;
+            let mut math = math_calls(&w, &mut p)?;
+            if p != w.len() {
+                return Err("trailing camera words".into());
+            }
+            let mut entity = urt_gameplay::transition::CameraEntity {
+                origin: [0x12345678; 3],
+                clear: [0x12345678; 6],
+            };
+            let blank = urt_gameplay::transition::CameraPlayer {
+                movement: 0xaabbccdd,
+                origin: [0xaabbccdd; 3],
+                velocity: [0xaabbccdd; 3],
+                field104: 0xaabbccdd,
+                angles: [0xaabbccdd; 3],
+                mode3108: 0xaabbccdd,
+                field4324: 0xaabbccdd,
+            };
+            let mut clients = [blank.clone(), blank];
+            let (out, spawn) = configure_camera_with_spawns(
+                &world,
+                &blocked,
+                &mut state,
+                &mut math,
+                &mut entity,
+                &mut clients[slot],
+            )
+            .map_err(|e| format!("{e:?}"))?;
+            math.finish().map_err(|e| format!("{e:?}"))?;
+            let e = word_object(
+                &[4, 8, 92, 96, 100, 156, 160, 180, 460],
+                &[
+                    entity.clear[0],
+                    entity.clear[1],
+                    entity.origin[0],
+                    entity.origin[1],
+                    entity.origin[2],
+                    entity.clear[2],
+                    entity.clear[3],
+                    entity.clear[4],
+                    entity.clear[5],
+                ],
+            );
+            let clients = clients
+                .iter()
+                .map(|p| {
+                    word_object(
+                        &[4, 20, 24, 28, 32, 36, 40, 104, 152, 156, 160, 3108, 4324],
+                        &[
+                            p.movement,
+                            p.origin[0],
+                            p.origin[1],
+                            p.origin[2],
+                            p.velocity[0],
+                            p.velocity[1],
+                            p.velocity[2],
+                            p.field104,
+                            p.angles[0],
+                            p.angles[1],
+                            p.angles[2],
+                            p.mode3108,
+                            p.field4324,
+                        ],
+                    )
+                })
+                .collect::<Vec<_>>()
+                .join(",");
+            let effects = out
+                .effects
+                .iter()
+                .map(|e| match e {
+                    CameraEffect::FindClass => 276433,
+                    CameraEffect::Fallback => 168114,
+                    CameraEffect::PickTarget => 276586,
+                    CameraEffect::Angles => 62944,
+                })
+                .collect::<Vec<_>>();
+            let matches = out.matches.iter().map(|j| *j as u32).collect::<Vec<_>>();
+            let diagnostic = match out.diagnostic {
+                None => "null",
+                Some(TargetDiagnostic::Null) => "\"null\"",
+                Some(TargetDiagnostic::Missing) => "\"missing\"",
+            };
+            let spawn_index = spawn.as_ref().map(|v| v.index as i32).unwrap_or(-1);
+            let spawn_candidates = array(
+                &spawn
+                    .as_ref()
+                    .map(|v| v.candidates.iter().map(|j| *j as u32).collect::<Vec<_>>())
+                    .unwrap_or_default(),
+            );
+            Ok(format!(
+                "{{\"spawn_index\":{spawn_index},\"spawn_candidates\":{spawn_candidates},\"class_index\":{},\"target_index\":{},\"rng_state\":{state},\"matches\":{},\"diagnostic\":{diagnostic},\"effects\":{},\"view\":{{\"origin\":{},\"angles\":{}}},\"entity\":{e},\"clients\":[{clients}]}}",
+                out.class_index.map(|j| j as i32).unwrap_or(-1),
+                out.target_index.map(|j| j as i32).unwrap_or(-1),
+                array(&matches),
+                array(&effects),
+                array(&out.view.origin),
+                array(&out.view.angles)
+            ))
+        }
         _ => Err("unknown command".into()),
     }
 }

crates/urt-gameplay/src/camera_world.rs

@@ -709,3 +709,128 @@ mod spawn_tests {
         assert_eq!(state, 42);
     }
 }
+
+/// Configure a camera with actual recovered fallback selection. Telefrag flags
+/// are resolved by the caller; math responses remain supplied through AngleMath.
+pub fn configure_camera_with_spawns<M: AngleMath>(
+    world: &[WorldEntity],
+    blocked: &[bool],
+    state: &mut u32,
+    math: &mut M,
+    entity: &mut crate::transition::CameraEntity,
+    player: &mut crate::transition::CameraPlayer,
+) -> Result<(CameraResolution, Option<SpawnSelection>), Error> {
+    if blocked.len() != world.len() {
+        return Err(Error::InvalidCount);
+    }
+    let classes = world.iter().map(|e| e.class).collect::<Vec<_>>();
+    if find_class(&classes, world.len(), None, (-2104846030i32) as u32)?.is_some() {
+        return Ok((
+            configure_camera(
+                world,
+                state,
+                crate::transition::View {
+                    origin: [0; 3],
+                    angles: [0; 3],
+                },
+                math,
+                entity,
+                player,
+            )?,
+            None,
+        ));
+    }
+    let spawns = world
+        .iter()
+        .zip(blocked)
+        .map(|(e, b)| SpawnEntity {
+            class: e.class,
+            blocked: *b,
+            origin: e.origin,
+            angles: e.angles,
+        })
+        .collect::<Vec<_>>();
+    let selected = fallback_spawn(&spawns, [0; 3], state, math)?;
+    let camera = CameraResolution {
+        class_index: None,
+        target_index: None,
+        matches: vec![],
+        diagnostic: None,
+        effects: vec![CameraEffect::FindClass, CameraEffect::Fallback],
+        view: selected.view,
+    };
+    crate::transition::place_camera(entity, player, selected.view.origin, selected.view.angles);
+    Ok((camera, Some(selected)))
+}
+#[cfg(test)]
+mod composed_spawn_tests {
+    use super::*;
+    use crate::transition::{CameraEntity, CameraPlayer};
+    fn player() -> CameraPlayer {
+        CameraPlayer {
+            movement: 7,
+            origin: [7; 3],
+            velocity: [7; 3],
+            field104: 7,
+            angles: [7; 3],
+            mode3108: 2,
+            field4324: 3,
+        }
+    }
+    #[test]
+    fn blocked_spawn_still_places_offset_fallback() {
+        let e = WorldEntity {
+            class: HashEntity {
+                in_use: 1,
+                class_present: true,
+                class_hash: (-103258081i32) as u32,
+            },
+            origin: [0, 0, 2.0f32.to_bits()],
+            angles: [4; 3],
+            aim: None,
+            label: None,
+        };
+        let mut state = 9;
+        let mut entity = CameraEntity {
+            origin: [7; 3],
+            clear: [7; 6],
+        };
+        let mut player = player();
+        let (out, spawn) = configure_camera_with_spawns(
+            &[e],
+            &[true],
+            &mut state,
+            &mut HostMath,
+            &mut entity,
+            &mut player,
+        )
+        .unwrap();
+        assert_eq!(spawn.unwrap().index, 0);
+        assert_eq!(out.view.origin[2], 11.0f32.to_bits());
+        assert_eq!(entity.origin, out.view.origin);
+        assert_eq!(state, 9);
+    }
+    #[test]
+    fn no_spawn_rejects_without_placement() {
+        let mut state = 9;
+        let mut entity = CameraEntity {
+            origin: [7; 3],
+            clear: [7; 6],
+        };
+        let old = entity.clone();
+        let mut player = player();
+        assert_eq!(
+            configure_camera_with_spawns(
+                &[],
+                &[],
+                &mut state,
+                &mut HostMath,
+                &mut entity,
+                &mut player
+            ),
+            Err(Error::NoSpawn)
+        );
+        assert_eq!(entity, old);
+        assert_eq!(state, 9);
+    }
+}

docs/FINDINGS.md

@@ -1598,3 +1598,6 @@ RE-813–822 replaces the scoreboard decimal assumption with actual37914 executi
 
 
 **RE-866:** 128 coherent setup→placement cases replace supplied fallback view writes with actual168114 selection, composing searches, capped distance ranking, RNG and angle execution. Existing intermission-camera paths and two player indirections are checked together. Telefrag answers and finite native math remain supplied; respawn/runtime integration is open. [Evidence](research/QVM_CAMERA_SPAWN.md).
+
+
+**RE-867:** Rust matches128 continuous source camera/fallback/placement cases with shared RNG state and checked native-math transcripts. The supplied fallback view has been replaced by recovered spawn ranking and +9 Z. Telefrag answers stay caller-owned; no-spawn errors preserve placement state. Native collision/math and runtime integration remain open. [Evidence](research/RUST_CAMERA_SPAWN.md).

docs/PROVISIONAL_TODO.md

@@ -1623,3 +1623,6 @@ RE-865: Rust matches112 original fallback cases with checked distance-math respo
 
 
 RE-866: 128 coherent setup→placement cases replace supplied fallback view writes with actual168114 selection, composing searches, capped distance ranking, RNG and angle execution. Existing intermission-camera paths and two player indirections are checked together. Telefrag answers and finite native math remain supplied; respawn/runtime integration is open. Full runtime completion remains open. [Evidence](research/QVM_CAMERA_SPAWN.md).
+
+
+RE-867: Rust matches128 continuous source camera/fallback/placement cases with shared RNG state and checked native-math transcripts. The supplied fallback view has been replaced by recovered spawn ranking and +9 Z. Telefrag answers stay caller-owned; no-spawn errors preserve placement state. Native collision/math and runtime integration remain open. Full runtime completion remains open. [Evidence](research/RUST_CAMERA_SPAWN.md).

docs/RESEARCH_LEDGER.md

@@ -2031,3 +2031,8 @@ Rust matches112 original fallback cases with checked distance-math responses, st
 128 coherent setup→placement cases replace supplied fallback view writes with actual168114 selection, composing searches, capped distance ranking, RNG and angle execution. Existing intermission-camera paths and two player indirections are checked together. Telefrag answers and finite native math remain supplied; respawn/runtime integration is open. Focused `cargo xtask test-group camera-spawn` passes (5 Python tests); selected reports regenerate twice deterministically, with storage, documentation links and whitespace guards. Full suite deferred to task ten. Original assets unchanged; source fixtures do not establish complete native/runtime parity.
 
 RE-866 review: expanded the standalone source fallback grid to80 entities so filtering still leaves more than64 matches, and asserted actual cap coverage. Focused spawn-fallback regeneration and downstream Rust parity checks pass (9 Python tests); existing case count remains112.
+
+
+## 2026-10-27 — RE-867 Rust camera composition with recovered fallback
+
+Rust matches128 continuous source camera/fallback/placement cases with shared RNG state and checked native-math transcripts. The supplied fallback view has been replaced by recovered spawn ranking and +9 Z. Telefrag answers stay caller-owned; no-spawn errors preserve placement state. Native collision/math and runtime integration remain open. Focused `cargo xtask test-group rust-camera-spawn` passes (9 Python tests); selected reports regenerate twice deterministically, with storage, documentation links and whitespace guards. Full suite deferred to task ten. Original assets unchanged; source fixtures do not establish complete native/runtime parity.

docs/REVERSE_ENGINEERING_TODO.md

@@ -1660,3 +1660,6 @@ Purpose: turn the supplied installation into an evidence-backed specification of
 
 
 - [x] RE-866 Original camera setup with actual fallback spawn selection ([evidence](research/QVM_CAMERA_SPAWN.md)).
+
+
+- [x] RE-867 Rust camera composition with recovered fallback ([evidence](research/RUST_CAMERA_SPAWN.md)).

docs/research/README.md

@@ -1196,3 +1196,6 @@ The extension collector adds five focused tests for native tail calls, command-r
 
 
 [RE-866: Original camera setup with actual fallback spawn selection](QVM_CAMERA_SPAWN.md).
+
+
+[RE-867: Rust camera composition with recovered fallback](RUST_CAMERA_SPAWN.md).

docs/research/RUST_CAMERA_SPAWN.md

@@ -0,0 +1,7 @@
+# Rust camera composition with recovered fallback
+
+RE-867. Reproduce with `python3 scripts/analyze_rust_camera_spawn.py`; focused validation: `cargo xtask test-group rust-camera-spawn`. [Machine report](rust-camera-spawn.json).
+
+Rust matches128 continuous source camera/fallback/placement cases with shared RNG state and checked native-math transcripts. The supplied fallback view has been replaced by recovered spawn ranking and +9 Z. Telefrag answers stay caller-owned; no-spawn errors preserve placement state. Native collision/math and runtime integration remain open.
+
+Original executable/native runtime and complete Linux/macOS Rust/Bevy/Solari acceptance remain unverified.

docs/research/rust-health-impulse.json

@@ -2985,7 +2985,7 @@
       "exit_code": 2
     }
   ],
-  "rust_unit_tests": 121,
+  "rust_unit_tests": 123,
   "source_report": "docs/research/qvm-health-impulse.json",
   "source_report_sha256": "625fd8064004ea6dbdf398d51d0af844d9c635ff04c0a0790886dddb6ab81e71"
 }

scripts/analyze_rust_camera_spawn.py

@@ -0,0 +1,20 @@
+#!/usr/bin/env python3
+import hashlib,json
+from pathlib import Path
+from rust_camera_world_support import binary,result,invoke
+from analyze_qvm import write_json
+from analyze_qvm_camera_spawn import scene
+def encode(s):
+ a=s['input'];c,fallback=scene(a['layout'],a['profile'],a['spawns'],a['blocked']);out=[a['seed'],a['slot'],len(c),*fallback[0],*fallback[1]]
+ from rust_camera_world_support import blob
+ for e in c:out.extend([e['active'],e['name'],e['hash'],*e['origin'],*e['angles'],*blob(None if e['aim'] is None else e['aim'].hex()),*blob(None if e['label'] is None else e['label'].hex())])
+ out.extend(int(e.get('blocked',False)) for e in c);out.append(len(s['math']))
+ for m in s['math']:out.extend([m['target'],m['arguments']['8'],m['arguments'].get('12',0),m['result']])
+ return out
+def project(s):return {k:s[k] for k in ['spawn_index','spawn_candidates','class_index','target_index','rng_state','matches','diagnostic','effects','view','entity','clients']}
+
+def main():
+ b=binary();p=Path('docs/research/qvm-camera-spawn.json');data=p.read_bytes();rows=[]
+ for s in json.loads(data)['probes']:rows.append({'source':project(s),'rust':result(b,'spawn-camera',encode(s))})
+ write_json(Path('docs/research/rust-camera-spawn.json'),{'source_report':str(p),'source_report_sha256':hashlib.sha256(data).hexdigest(),'probes':rows,'limits':'Rust matches128 continuous source camera/fallback/placement cases with shared RNG state and checked native-math transcripts. The supplied fallback view has been replaced by recovered spawn ranking and +9 Z. Telefrag answers stay caller-owned; no-spawn errors preserve placement state. Native collision/math and runtime integration remain open.'})
+if __name__=='__main__':main()

scripts/test_rust_camera_spawn.py

@@ -0,0 +1,9 @@
+import hashlib,json,unittest
+from pathlib import Path
+class PortTests(unittest.TestCase):
+ def test_all_original_cases(self):
+  r=json.loads(Path('docs/research/rust-camera-spawn.json').read_text());src=json.loads(Path(r['source_report']).read_text());self.assertEqual(len(r['probes']),len(src['probes']));self.assertGreater(len(r['probes']),20)
+  for p in r['probes']:self.assertEqual(p['rust'],p['source'])
+ def test_source_identity(self):
+  r=json.loads(Path('docs/research/rust-camera-spawn.json').read_text());self.assertEqual(hashlib.sha256(Path(r['source_report']).read_bytes()).hexdigest(),r['source_report_sha256'])
+if __name__=='__main__':unittest.main()

xtask/checks.tsv

@@ -2446,3 +2446,17 @@ report	scripts/analyze_qvm_camera_spawn.py	docs/research/qvm-camera-spawn.json
 edge	docs/research/qvm-camera-spawn.json	scripts/test_qvm_camera_spawn.py
 group	camera-spawn	scripts/analyze_qvm_camera_spawn.py
 edge	scripts/analyze_qvm_camera_spawn.py	scripts/analyze_qvm_resumer_audit.py
+edge	Cargo.toml	scripts/analyze_rust_camera_spawn.py
+edge	Cargo.lock	scripts/analyze_rust_camera_spawn.py
+edge	crates/urt-gameplay/Cargo.toml	scripts/analyze_rust_camera_spawn.py
+edge	crates/urt-gameplay/src/lib.rs	scripts/analyze_rust_camera_spawn.py
+edge	crates/urt-gameplay/src/camera_world.rs	scripts/analyze_rust_camera_spawn.py
+edge	crates/urt-gameplay/src/bin/urt-camera-world.rs	scripts/analyze_rust_camera_spawn.py
+edge	docs/research/qvm-camera-spawn.json	scripts/analyze_rust_camera_spawn.py
+group	rust-camera-spawn	scripts/analyze_rust_health_impulse.py
+group	gameplay	scripts/analyze_rust_camera_spawn.py
+edge	crates/urt-gameplay/src/transition.rs	scripts/analyze_rust_camera_spawn.py
+report	scripts/analyze_rust_camera_spawn.py	docs/research/rust-camera-spawn.json
+edge	docs/research/rust-camera-spawn.json	scripts/test_rust_camera_spawn.py
+group	rust-camera-spawn	scripts/analyze_rust_camera_spawn.py
+edge	scripts/analyze_rust_camera_spawn.py	scripts/analyze_qvm_resumer_audit.py