Merge pull request #63 from MHFU-ModKit/tail/attach

A port's tail tip: whole until the cut, then it drops

Author: sp00ktober

apps/blender/src/mhfu_blender/write.py

@@ -5,7 +5,8 @@
 What Blender holds comes in as plain data: the bind joints, each group's geometry and each slot's
 clip. An MHFU model keeps every byte no edit reaches: a group whose vertex count and triangles are
 unchanged is written in place, at the PMO's own size; any other is rebuilt and the PMO laid out
-again. An MHP3rd model comes out as an MHFU PAC with geometry, skeleton and textures, no clips.
+again. An MHP3rd model comes out as an MHFU PAC with geometry, skeleton and textures, no clips;
+its tail tip, when its skeleton has one, in mesh record 1 (`mhfu_port.mesh.build`).
 """
 
 from __future__ import annotations
@@ -16,7 +17,7 @@
 
 import numpy as np
 from mhfu import inject
-from mhfu_port import constraints, fk, mesh, motion
+from mhfu_port import constraints, fk, mesh, motion, rig
 from mhfu_port.mesh import Part, Skinned
 from mhfu_port.model import ANIMATION, MHFU, MODEL, SKELETON, MeshGroup, Model
 from mhp_formats import fu, pmo
@@ -328,13 +329,13 @@ def _donor(model: Model, skeleton: Skeleton, groups: Mapping[int, Geometry]) ->
             f"{len(over)} positions outside the model's {_box(scale)} box, first group "
             f"{kept[o.group]} vertex {o.vertex}"
         )
+    bones = [replace(b, name=None) for b in skeleton.bones]
+    fu_skeleton = Skeleton(bones, list(skeleton.params), magic=FU_MAGIC)
     try:
-        out = mesh.build(skinned, scale)
+        out = mesh.build(skinned, scale, tip=rig.tip_of(fu_skeleton))
     except ValueError as e:
         raise ExportError(str(e)) from None
     notes[:0] = ["no clips: an in-game monster from an MHP3rd one is a port, built from a manifest"]
-    bones = [replace(b, name=None) for b in skeleton.bones]
-    fu_skeleton = Skeleton(bones, list(skeleton.params), magic=FU_MAGIC)
     results = _judge(constraints.validate(out, fu_skeleton), [])
     tmh = next((e for e in entries if Tmh.sniff(e)), b"")
     pac = [fu_skeleton.to_bytes(), out.to_bytes(), tmh, EMPTY_ANIM.to_bytes()]

apps/blender/tests/conftest.py

@@ -97,7 +97,7 @@ def synthetic_pac() -> bytes:
     uvs = [(0.0, 0.0), (1.0, 0.0), (0.0, 1.0)]
     influences = [[(1, 1.0)], [(1, 0.25), (2, 0.75)], [(1, 1.0)]]
     part = Part(verts, [], uvs, [], [(0, 1, 2)], influences, 0)
-    model = mesh.build([Skinned(part, part.influences)], (256.0, 256.0, 256.0))
+    model = mesh.build([Skinned(part, part.influences)], (256.0, 256.0, 256.0), tip=None)
     root = Track(
         [
             Channel(0x008, keys((0, 0, 0, 300), (10, 2048, -100, 50), (20, 0))),
@@ -159,7 +159,7 @@ def donor_pac() -> bytes:
     weights = [[(1, 1.0)], [(1, 0.25), (2, 0.75)], [(1, 1.0)], [(2, 1.0)]]
     part = Part(verts, normals, uvs, [], [(0, 1, 2), (2, 1, 3)], weights, 0)
     scale = (256.0, 256.0, 256.0)
-    built = mesh.build([Skinned(part, part.influences)], scale)
+    built = mesh.build([Skinned(part, part.influences)], scale, tip=None)
     model = p3rd.Pmo(
         [p3rd.Mesh(built.groups(), [0], scale=scale)], built.materials, scale, remap_table=False
     )

apps/blender/tests/test_write.py

@@ -9,7 +9,8 @@
 
 import numpy as np
 import pytest
-from mhfu_port import motion
+from mhfu_port import build, manifest, motion, verify
+from mhfu_port.data import Data
 from mhfu_port.model import Model
 from mhp_formats import Pac, Pmo, Tmh, fu
 from mhp_formats.anim import Channel, Clip, Keyframe, Track
@@ -209,6 +210,27 @@ def test_donor(write: ModuleType, donor: bytes) -> None:
         write.place(out.pac, model)
 
 
+@pytest.mark.parametrize("side", ["source", "port"])
+def test_zinogre_tip(write: ModuleType, mhfu_data: Path, mhp3rd_data: Path, side: str) -> None:
+    """An export of the Zinogre, its MHP3rd model or its port edited, keeps the tail tip in mesh
+    record 1, which the Tigrex's dropped tail draws: verify's tip check passes."""
+    if side == "source":
+        model = Model.from_path(mhp3rd_data / "file_05339.bin")
+        groups = None
+    else:
+        games = Data.find(mhfu_data, mhp3rd_data)
+        ports = Path(__file__).parents[3] / "ports"
+        pac = build.build(manifest.load(ports / "zinogre.toml"), games).pac
+        model = Model.from_bytes(pac, "file_06185")
+        groups = held(write, model)
+        groups[0].positions[0] += (3.0, -2.0, 1.5)
+    port = verify.Port(export(write, model, groups).pac)
+    host = verify.Port((mhfu_data / "file_06185.bin").read_bytes())
+    check = verify.tip_check(port, host)
+    assert check.ok, check.detail
+    assert len(port.model.meshes[1].groups) == 6
+
+
 def test_place(write: ModuleType, model: Model, tmp_path: Path) -> None:
     root = tmp_path / "memstick"
     (root / "PSP").mkdir(parents=True)

apps/studio/src/mhfu_studio/monster/clips.py

@@ -179,16 +179,16 @@ def coverage(
     port: AnimPack,
     host: AnimPack | None = None,
     donor: Mapping[int, anim.Clip] | None = None,
-    layout: Mapping[int, int] | None = None,
+    layout: layouts.Layout | None = None,
 ) -> Coverage:
-    """Each entry of a built pack against the donor clip `layout` (entry -> MHP3rd id; by
-    default each entry read as the clip of its own id) puts there and the host's pack; every
-    entry is UNKNOWN without the donor."""
+    """Each entry of a built pack against the donor clip `layout` puts there (by default each
+    entry read as the clip of its own id) and the host's pack; every entry is UNKNOWN without
+    the donor."""
     table = clip_table(port)
     host_table = clip_table(host) if host is not None else {}
     donor = donor or {}
     if layout is None:
-        layout = {cid: cid for cid in donor if cid in table}
+        layout = layouts.Layout({cid: cid for cid in donor if cid in table})
     held = slots.correspondence(port, donor, layout) if donor else {}
     cov = Coverage(has_source=bool(donor), has_host=host is not None)
     for slot, fp in sorted(table.items()):
@@ -201,11 +201,11 @@ def coverage(
             kind = FILLER
         else:
             kind = HOST if host_table.get(slot) == fp else ALTERED
-        cid = layout.get(slot)
+        cid = layout.entries.get(slot)
         fp_src = fingerprint(donor[cid]) if cid is not None and cid in donor else None
         cov.slots[slot] = SlotCoverage(slot, kind, fp[0], fp[1], fp_src, cid)
     if host is not None:
-        placed = set(layout.values())
+        placed = set(layout.entries.values())
         cov.dropped = {cid: fingerprint(c) for cid, c in donor.items() if cid not in placed}
     return cov
 

apps/studio/src/mhfu_studio/monster/commands.py

@@ -117,6 +117,7 @@ def _render(groups: Groups) -> None:
     p.add_argument("--no-grid", action="store_true", help="hide the ground plane")
     p.add_argument("--hilite", type=_ints, default=(), metavar="J,J,..", help="paint joints red")
     p.add_argument("--only", choices=("tagged", "rest"), help="draw only --hilite, or the rest")
+    p.add_argument("--severed", action="store_true", help="the stump: the tail tip hidden")
     data.add_arguments(p)
     flags.add_flags(p)
     p.set_defaults(run=run_render)
@@ -168,6 +169,7 @@ def run_render(args: argparse.Namespace) -> int:
         grid=not args.no_grid,
         hilite=args.hilite,
         only=args.only,
+        severed=args.severed,
     )
     return flags.finish(args, shots.render(sc, o, args.size, args.samples))
 
@@ -267,7 +269,7 @@ def run_clips(args: argparse.Namespace) -> int:
     port = slots.anim_of(b.pac)
     table = clips.clip_table(port)
     host, donor = inputs.host_anim(m, games), inputs.donor_clips(m, games)
-    cov = clips.coverage(port, host, donor, layout.of(m, donor, host).entries)
+    cov = clips.coverage(port, host, donor, layout.of(m, donor, host))
     if args.import_labels:
         labels = slots.read_labels(args.import_labels.read_text(encoding="utf-8"))
         provenance = args.labels_from or clips.UNRECORDED.format(args.import_labels.name)

apps/studio/src/mhfu_studio/monster/core/scene.py

@@ -1,15 +1,16 @@
 # SPDX-License-Identifier: GPL-3.0-or-later
 # SPDX-FileCopyrightText: 2026 sp00ktober
 """A monster PAC as the studio opens it: `mhfu_port.model.Model` with a port manifest's clip
-names, the file's build id and `pose()`."""
+names, the file's build id and `pose()`, its tail tip on the tail unless `severed`."""
 
 from __future__ import annotations
 
 from collections.abc import Sequence
+from functools import cached_property
 from pathlib import Path
 from typing import Any, Self
 
-from mhfu_port import build, layout
+from mhfu_port import build, fk, layout, mesh, rig
 from mhfu_port.data import Data
 from mhfu_port.manifest import Manifest
 from mhfu_port.model import MHP3RD, Clip, Model
@@ -32,6 +33,8 @@ def __init__(self, *args: Any, **kw: Any) -> None:
             None if self.path is None or self.pac is None else build_id(self.path.name, self.pac)
         )
         """`name@digest` of the file, what clip labels are keyed to."""
+        self.severed = False
+        """Draw the stump: the tail tip hidden, not posed on the tail."""
 
     @classmethod
     def from_bytes(
@@ -97,17 +100,51 @@ def attach_manifest(self, m: Manifest) -> None:
                 by_slot.setdefault(at, []).append(name)
         self.rename(by_slot)
 
+    # the tail tip
+
+    @cached_property
+    def tip(self) -> rig.Tip | None:
+        """`rig.tip_of` the skeleton; None, with a note, where no offset pairs the chain."""
+        try:
+            return rig.tip_of(self.skeleton)
+        except ValueError as e:
+            self.notes.append(f"the tail tip stays where it is stored: {e}")
+            return None
+
+    def tip_groups(self) -> list[int]:
+        """The groups riding only the tip's chain (`mesh.tip_parts`)."""
+        if self.tip is None:
+            return []
+        rows = [
+            [
+                list(zip(js, ws, strict=True))
+                for js, ws in zip(g.skin.joints.tolist(), g.skin.weights.tolist(), strict=True)
+            ]
+            for g in self.groups
+        ]
+        return mesh.tip_parts(rows, self.tip.joints)
+
+    def hidden(self) -> set[int]:
+        """The groups not drawn: the tip's, when `severed`."""
+        return set(self.tip_groups()) if self.severed else set()
+
+    def world(self, rot: fk.Floats | None = None, loc: fk.Floats | None = None) -> fk.Floats:
+        """`fk.Rig.world`, the tip's chain posed as its carriers unless `severed`, as the game
+        does while the tail is whole."""
+        world = self.rig.world(rot, loc)
+        return world if self.severed or self.tip is None else fk.attach(world, self.tip.pairs)
+
     def clip_table(self) -> dict[int, tuple[int, bool]]:
         return {c.slot: (c.frames, c.loop) for c in self.clips}
 
     def pose(self, key: int | str | Clip, frame: float = 0.0) -> Pose:
         """Frames outside the clip hold per channel."""
         c = self.clip(key)
         rot, loc = self.curves(c).at(float(frame))
-        return Pose(self.rig, float(frame), self.rig.world(rot, loc), c.slot)
+        return Pose(self.rig, float(frame), self.world(rot, loc), c.slot)
 
     def bind_pose(self) -> Pose:
-        return Pose(self.rig, 0.0, self.rig.bind_world)
+        return Pose(self.rig, 0.0, self.world())
 
     # reporting
 

apps/studio/src/mhfu_studio/monster/render/mesh.py

@@ -258,10 +258,12 @@ def _upload_textures(ctx: moderngl.Context, scene: Scene) -> dict[int, moderngl.
 
 
 def _index_batches(ctx: moderngl.Context, scene: Scene) -> dict[int | None, moderngl.Buffer]:
-    """One index buffer per texture position; None holds the untextured groups."""
+    """One index buffer per texture position, `Scene.hidden` left out; None holds the
+    untextured groups."""
     parts: dict[int | None, list[npt.NDArray[np.int64]]] = {}
+    hidden = scene.hidden()
     for i, g in enumerate(scene.groups):
-        if g.n_faces:
+        if g.n_faces and i not in hidden:
             lo, _ = scene.group_range(i)
             parts.setdefault(g.texture, []).append(g.triangles.astype(np.int64) + lo)
     return {t: ctx.buffer(np.concatenate(p).astype("i4").tobytes()) for t, p in parts.items()}

apps/studio/src/mhfu_studio/monster/render/playback.py

@@ -191,7 +191,7 @@ def pose_at(
         if js:
             loc = loc.copy()
             loc[js] = curves.at(0.0)[1][js]
-    world = scene.rig.world(rot, loc)
+    world = scene.world(rot, loc)
     th = yaw_at(scene, clip, frame, steer, speed)
     if th:
         world = yaw_matrix(th) @ world

apps/studio/src/mhfu_studio/monster/render/shots.py

@@ -36,6 +36,8 @@ class Options:
     grid: bool = True
     hilite: Sequence[int] = ()
     only: str | None = None
+    severed: bool = False
+    """The stump: the tail tip hidden (`Scene.severed`)."""
 
 
 def configure(vp: MonsterViewport, o: Options) -> None:
@@ -77,6 +79,7 @@ def render(
     """`<clip>_f<frame>_<view>` per frame and view (`bind_<view>` for the bind pose), each framed
     on its own pose."""
     images: dict[str, Image8] = {}
+    scene.severed = o.severed
     with offscreen(lambda c: MonsterViewport(c, size, samples), ctx) as vp:
         vp.set_scene(scene)
         configure(vp, o)

apps/studio/src/mhfu_studio/monster/render/viewport.py

@@ -76,7 +76,7 @@ def pose(self, clip: Clip | None, frame: float = 0.0) -> None:
             steer=self.steer,
             speed=self.playback.speed,
         )
-        self.mesh.set_pose(None if clip is None else p)
+        self.mesh.set_pose(p)  # bind included: the tail tip moves onto the tail
         self.skeleton.set_positions(p.joints)
         for ov in (self.hitboxes, self.attacks):
             if ov is not None: