Decals: explosion scorch pool + cover damage-cracks + room-arena scars (Phase 1.5b bundle 2)

All procedural, client-only, observe-only in PresentationSystemGroup, zero netcode surface (read existing replicated state). Shared FeedbackFx decal primitives (scorch blob + crack star meshes + transparent decal material). ScorchDecalSystem: static RequestScorch queue -> pooled fading discs (mirrors DynamicLightSystem), wired from the barrel boom, reusable by the geyser. CoverDamageSystem: crack accretion keyed on BlightClutter.Remaining (Variant 4) + proximity-gated shatter-scorch. RoomDressingSystem: persistent arena scars on a distinct hash sub-stream, torn down with dressing. Knobs in DecalConfig. Cover cracks use decals (not URPMaterialPropertyBaseColor) because the Synty prop shader is not Hybrid-Per-Instance. Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
2026-07-12 12:58:33 -07:00
parent b3ef846fb8
commit 649f656833
9 changed files with 528 additions and 0 deletions
@@ -14,6 +14,11 @@ namespace ProjectM.Client
    /// (0xC17). Deterministic from the replicated run seed: every co-op client (and a late-joiner) sees the
    /// same floor. Torn down when the room changes or the run ends. Colliders + rigidbodies are stripped on
    /// spawn — the aim-reticle raycast and the physics world must never see dressing. Never mutates the sim.
+    /// <para>
+    /// Bundle 2 (decals): also lays a few persistent feathered crack/scorch DETAIL scars at the arena centre
+    /// (higher-frequency detail the baked ground splat can't resolve), on its own hash sub-stream, parented to
+    /// the same dressing root so they tear down together. Base POIs are skipped — Part O baked their wear in.
+    /// </para>
    /// </summary>
    [WorldSystemFilter(WorldSystemFilterFlags.ClientSimulation)]
    [UpdateInGroup(typeof(PresentationSystemGroup))]
@@ -22,6 +27,13 @@ namespace ProjectM.Client
        Transform _root;
        uint _activeKey;

+        // Bundle 2 arena-scar decal assets (reused across rebuilds; the scar GameObjects are children of _root and
+        // torn down each room change, these shared assets persist until OnDestroy).
+        Material _decalMat;
+        Mesh[] _decalMeshes;
+        MaterialPropertyBlock _decalMpb;
+        static readonly int DecalColorId = Shader.PropertyToID("_Color");
+
        protected override void OnStartRunning()
        {
            if (_root == null) _root = new GameObject("~RoomDressing").transform;
@@ -30,6 +42,10 @@ namespace ProjectM.Client
        protected override void OnDestroy()
        {
            if (_root != null) Object.Destroy(_root.gameObject);
+            if (_decalMat != null) Object.Destroy(_decalMat);
+            if (_decalMeshes != null)
+                for (int i = 0; i < _decalMeshes.Length; i++)
+                    if (_decalMeshes[i] != null) Object.Destroy(_decalMeshes[i]);
        }

        protected override void OnUpdate()
@@ -106,6 +122,51 @@ namespace ProjectM.Client
                foreach (var col in go.GetComponentsInChildren<Collider>(true)) Object.Destroy(col);
                foreach (var rb in go.GetComponentsInChildren<Rigidbody>(true)) Object.Destroy(rb);
            }
+
+            // Bundle 2 arena scars: distinct hash sub-stream (0xD2E56) so they never co-locate with the prop
+            // scatter (0xD2E55); clustered around the arena centre. Persistent (no fade); torn down with dressing.
+            if (DecalConfig.Enabled && DecalConfig.RoomArenaDecalCount > 0)
+            {
+                EnsureDecalAssets();
+                var srng = new Unity.Mathematics.Random(RunMapMath.Hash(ri.RunSeed, (uint)(ri.CurrentRoom + 1), 0xD2E56u) | 1u);
+                for (int i = 0; i < DecalConfig.RoomArenaDecalCount; i++)
+                    SpawnArenaScar(origin, i, ref srng);
+            }
+        }
+
+        void EnsureDecalAssets()
+        {
+            if (_decalMat == null) _decalMat = FeedbackFx.MakeDecalMaterial("RoomScarDecal");
+            if (_decalMpb == null) _decalMpb = new MaterialPropertyBlock();
+            if (_decalMeshes == null)
+            {
+                _decalMeshes = new Mesh[4];
+                _decalMeshes[0] = FeedbackFx.BuildScorchMesh(20, 0.32f, 11);
+                _decalMeshes[1] = FeedbackFx.BuildScorchMesh(20, 0.34f, 23);
+                _decalMeshes[2] = FeedbackFx.BuildCrackMesh(3, 31);
+                _decalMeshes[3] = FeedbackFx.BuildCrackMesh(2, 47);
+            }
+        }
+
+        void SpawnArenaScar(float3 origin, int index, ref Unity.Mathematics.Random rng)
+        {
+            var go = new GameObject("ArenaScar");
+            go.transform.SetParent(_root, false);
+            go.AddComponent<MeshFilter>().sharedMesh = _decalMeshes[rng.NextInt(0, _decalMeshes.Length)];
+            var mr = go.AddComponent<MeshRenderer>();
+            mr.sharedMaterial = _decalMat;
+            mr.shadowCastingMode = UnityEngine.Rendering.ShadowCastingMode.Off;
+            mr.receiveShadows = false;
+            mr.lightProbeUsage = UnityEngine.Rendering.LightProbeUsage.Off;
+            _decalMpb.SetColor(DecalColorId, DecalConfig.RoomDecalColor);
+            mr.SetPropertyBlock(_decalMpb);
+            float ang = rng.NextFloat(0f, math.PI * 2f);
+            float rad = rng.NextFloat(0f, 4.5f); // clustered around the arena centre where the fight happens
+            float scale = rng.NextFloat(1.4f, 3.0f);
+            go.transform.SetPositionAndRotation(
+                new Vector3(origin.x + math.cos(ang) * rad, 0.05f + 0.003f * index, origin.z + math.sin(ang) * rad),
+                Quaternion.Euler(0f, rng.NextFloat(0f, 360f), 0f));
+            go.transform.localScale = new Vector3(scale, 1f, scale);
        }
    }
 }