Unified, portable Unreal Engine MCP system plugin
Merge of the two project copies into one self-contained plugin (the superset: variable_op + variables.py, full pcg_op runtime/declarative/preset ops, the CreateWidgetFloatAnimation widget tool, and full Voxel graph authoring). Made fully project- and machine-agnostic — no hardcoded paths: - New src/projectPaths.js auto-detects the host .uproject (walk-up), project name, Editor build target, log file, and engine install (EngineAssociation via launcher manifest/registry, else installed-engine scan). All overridable via UE_* env vars. - Rewired buildOrchestrator/insights/launcher/insightsExporter/server.js and the Python workers (cpp_scaffold, live_coding, apply_graph, console) off the old C:/Github/ihy, IHY*, E:/UE_Versions and UE_5.7 literals onto the resolver. - Voxel made optional: Build.cs auto-detects the Voxel plugin (env UE_MCP_WITH_VOXEL override) and the C++ compiles to stubs under WITH_MCP_VOXEL, so the module builds in projects without Voxel; .uplugin marks Voxel optional. - De-branded the agent-gateway and docs; scrubbed a leaked API key; excluded node_modules/Binaries/Intermediate/__pycache__/secrets from the repo. Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
This commit is contained in:
Bonchellon
271
ue_side/niagara.py
Normal file
271
ue_side/niagara.py
Normal file
@ -0,0 +1,271 @@
|
||||
"""Niagara authoring ops. Bridges to unreal.MCPNiagaraLibrary (C++) where
|
||||
editor-only APIs are required, falls back to pure Python where possible.
|
||||
|
||||
Ops:
|
||||
create_system {path}
|
||||
create_emitter_asset {path, template_emitter?} — create empty UNiagaraEmitter asset
|
||||
add_emitter {system, emitter_asset, name?} — add emitter to system, returns handle name
|
||||
remove_emitter {system, emitter_name}
|
||||
list_emitters {system}
|
||||
list_modules {system, emitter_name?, group} — group: EmitterSpawn|EmitterUpdate|ParticleSpawn|ParticleUpdate|SystemSpawn|SystemUpdate
|
||||
add_module {system, emitter_name?, group, module_script}
|
||||
remove_module {system, emitter_name?, group, module_name}
|
||||
add_renderer {system, emitter_name, renderer_class} — e.g. NiagaraSpriteRendererProperties
|
||||
remove_renderer {system, emitter_name, renderer_class}
|
||||
compile {system}
|
||||
set_module_input STUB — see NOTES at bottom.
|
||||
"""
|
||||
from __future__ import annotations
|
||||
|
||||
import json
|
||||
import os
|
||||
import traceback
|
||||
|
||||
try:
|
||||
import unreal # type: ignore
|
||||
except ImportError:
|
||||
unreal = None
|
||||
|
||||
|
||||
# ---------- loaders ----------
|
||||
|
||||
def _load_asset(path: str):
|
||||
if not path:
|
||||
return None
|
||||
return unreal.EditorAssetLibrary.load_asset(path)
|
||||
|
||||
|
||||
def _load_class(p: str):
|
||||
if not p:
|
||||
return None
|
||||
if "/" in p:
|
||||
return unreal.load_class(None, p)
|
||||
# Try common Niagara paths
|
||||
for prefix in ("/Script/Niagara.", "/Script/NiagaraEditor."):
|
||||
c = unreal.load_class(None, prefix + p)
|
||||
if c is not None:
|
||||
return c
|
||||
return unreal.load_class(None, p)
|
||||
|
||||
|
||||
def _lib():
|
||||
if not hasattr(unreal, "MCPNiagaraLibrary"):
|
||||
raise RuntimeError("MCPNiagaraLibrary not found — rebuild the UEBlueprintMCPEditor C++ module")
|
||||
return unreal.MCPNiagaraLibrary
|
||||
|
||||
|
||||
# ---------- ops ----------
|
||||
|
||||
def create_system(p):
|
||||
path = p["path"]
|
||||
ok = _lib().create_niagara_system(path)
|
||||
return {"ok": bool(ok), "path": path}
|
||||
|
||||
|
||||
def create_emitter_asset(p):
|
||||
"""Create an empty UNiagaraEmitter asset. Niagara typically doesn't support
|
||||
fully empty emitters via UI — users start from a template. We create the bare
|
||||
asset; for fully usable emitters duplicate an existing template via asset_op.
|
||||
"""
|
||||
path = p["path"]
|
||||
package_name, _, asset_name = path.rpartition("/")
|
||||
factory = unreal.NiagaraEmitterFactoryNew() if hasattr(unreal, "NiagaraEmitterFactoryNew") else None
|
||||
tools = unreal.AssetToolsHelpers.get_asset_tools()
|
||||
if factory is None:
|
||||
return {"ok": False, "error": "NiagaraEmitterFactoryNew not exposed to Python — duplicate a template emitter via asset_op instead"}
|
||||
asset = tools.create_asset(asset_name, package_name, unreal.NiagaraEmitter, factory)
|
||||
return {"ok": asset is not None, "path": path}
|
||||
|
||||
|
||||
def add_emitter(p):
|
||||
system = _load_asset(p["system"])
|
||||
emitter = _load_asset(p["emitter_asset"])
|
||||
if system is None or emitter is None:
|
||||
return {"ok": False, "error": "system or emitter_asset not found"}
|
||||
name = p.get("name", "")
|
||||
handle_name = _lib().add_emitter_to_system(system, emitter, name)
|
||||
if not handle_name:
|
||||
return {"ok": False, "error": "AddEmitterToSystem returned empty"}
|
||||
unreal.EditorAssetLibrary.save_asset(p["system"])
|
||||
return {"ok": True, "handle_name": handle_name}
|
||||
|
||||
|
||||
def remove_emitter(p):
|
||||
system = _load_asset(p["system"])
|
||||
if system is None:
|
||||
return {"ok": False, "error": "system not found"}
|
||||
ok = _lib().remove_emitter_from_system(system, p["emitter_name"])
|
||||
if ok:
|
||||
unreal.EditorAssetLibrary.save_asset(p["system"])
|
||||
return {"ok": bool(ok)}
|
||||
|
||||
|
||||
def list_emitters(p):
|
||||
system = _load_asset(p["system"])
|
||||
if system is None:
|
||||
return {"ok": False, "error": "system not found"}
|
||||
names = list(_lib().get_emitter_handle_names(system))
|
||||
return {"ok": True, "emitters": names}
|
||||
|
||||
|
||||
def list_modules(p):
|
||||
system = _load_asset(p["system"])
|
||||
if system is None:
|
||||
return {"ok": False, "error": "system not found"}
|
||||
modules = list(_lib().list_modules(system, p.get("emitter_name", ""), p["group"]))
|
||||
return {"ok": True, "modules": modules}
|
||||
|
||||
|
||||
def add_module(p):
|
||||
system = _load_asset(p["system"])
|
||||
script = _load_asset(p["module_script"])
|
||||
if system is None or script is None:
|
||||
return {"ok": False, "error": "system or module_script not found"}
|
||||
name = _lib().add_module_to_stack(
|
||||
system,
|
||||
p.get("emitter_name", ""),
|
||||
p["group"],
|
||||
script,
|
||||
int(p.get("index", -1)),
|
||||
)
|
||||
if not name:
|
||||
return {"ok": False, "error": "AddModuleToStack returned empty (wrong group or script not a module?)"}
|
||||
unreal.EditorAssetLibrary.save_asset(p["system"])
|
||||
return {"ok": True, "module_name": name}
|
||||
|
||||
|
||||
def remove_module(p):
|
||||
system = _load_asset(p["system"])
|
||||
if system is None:
|
||||
return {"ok": False, "error": "system not found"}
|
||||
ok = _lib().remove_module_from_stack(
|
||||
system,
|
||||
p.get("emitter_name", ""),
|
||||
p["group"],
|
||||
p["module_name"],
|
||||
)
|
||||
if ok:
|
||||
unreal.EditorAssetLibrary.save_asset(p["system"])
|
||||
return {"ok": bool(ok)}
|
||||
|
||||
|
||||
def add_renderer(p):
|
||||
system = _load_asset(p["system"])
|
||||
if system is None:
|
||||
return {"ok": False, "error": "system not found"}
|
||||
cls = _load_class(p["renderer_class"])
|
||||
if cls is None:
|
||||
return {"ok": False, "error": f"renderer class {p['renderer_class']!r} not found"}
|
||||
result = _lib().add_renderer_to_emitter(system, p["emitter_name"], cls)
|
||||
if not result:
|
||||
return {"ok": False, "error": "AddRendererToEmitter returned empty"}
|
||||
unreal.EditorAssetLibrary.save_asset(p["system"])
|
||||
return {"ok": True, "renderer": result}
|
||||
|
||||
|
||||
def remove_renderer(p):
|
||||
system = _load_asset(p["system"])
|
||||
if system is None:
|
||||
return {"ok": False, "error": "system not found"}
|
||||
cls = _load_class(p["renderer_class"])
|
||||
if cls is None:
|
||||
return {"ok": False, "error": f"renderer class {p['renderer_class']!r} not found"}
|
||||
n = int(_lib().remove_renderers_from_emitter(system, p["emitter_name"], cls))
|
||||
if n:
|
||||
unreal.EditorAssetLibrary.save_asset(p["system"])
|
||||
return {"ok": True, "removed": n}
|
||||
|
||||
|
||||
def assign_to_actor(p):
|
||||
"""Assign a UNiagaraSystem to the NiagaraComponent of a NiagaraActor in the
|
||||
current level. Identifies the actor by its label (use `name` field).
|
||||
"""
|
||||
system_path = p["system"]
|
||||
actor_name = p["name"]
|
||||
system = _load_asset(system_path)
|
||||
if system is None:
|
||||
return {"ok": False, "error": f"system {system_path!r} not found"}
|
||||
ess = unreal.get_editor_subsystem(unreal.EditorActorSubsystem)
|
||||
target = None
|
||||
for a in ess.get_all_level_actors():
|
||||
if a and (a.get_actor_label() == actor_name or a.get_name() == actor_name):
|
||||
target = a
|
||||
break
|
||||
if target is None:
|
||||
return {"ok": False, "error": f"actor {actor_name!r} not found"}
|
||||
comp = target.get_component_by_class(unreal.NiagaraComponent)
|
||||
if comp is None:
|
||||
return {"ok": False, "error": "actor has no NiagaraComponent"}
|
||||
comp.set_asset(system)
|
||||
comp.activate(reset=True)
|
||||
return {"ok": True, "actor": actor_name, "system": system_path}
|
||||
|
||||
|
||||
def compile_system(p):
|
||||
system = _load_asset(p["system"])
|
||||
if system is None:
|
||||
return {"ok": False, "error": "system not found"}
|
||||
ok = _lib().request_compile(system)
|
||||
return {"ok": bool(ok)}
|
||||
|
||||
|
||||
def set_module_input(p):
|
||||
return {
|
||||
"ok": False,
|
||||
"error": (
|
||||
"set_module_input not implemented yet — requires "
|
||||
"FNiagaraStackFunctionInputBinder + NiagaraClipboard plumbing. "
|
||||
"Workaround: open the system in editor and use UI, or extend "
|
||||
"MCPNiagaraLibrary with SetModuleInput(scalar|vector|enum) wrappers."
|
||||
),
|
||||
}
|
||||
|
||||
|
||||
OPS = {
|
||||
"create_system": create_system,
|
||||
"create_emitter_asset": create_emitter_asset,
|
||||
"add_emitter": add_emitter,
|
||||
"remove_emitter": remove_emitter,
|
||||
"list_emitters": list_emitters,
|
||||
"list_modules": list_modules,
|
||||
"add_module": add_module,
|
||||
"remove_module": remove_module,
|
||||
"add_renderer": add_renderer,
|
||||
"remove_renderer": remove_renderer,
|
||||
"compile": compile_system,
|
||||
"assign_to_actor": assign_to_actor,
|
||||
"set_module_input": set_module_input,
|
||||
}
|
||||
|
||||
|
||||
def entrypoint(payload_json: str) -> str:
|
||||
try:
|
||||
p = json.loads(payload_json)
|
||||
except Exception as e: # noqa: BLE001
|
||||
return _tee({"ok": False, "error": f"bad json: {e}"}, {})
|
||||
op = p.get("op")
|
||||
fn = OPS.get(op)
|
||||
if not fn:
|
||||
return _tee({"ok": False, "error": f"unknown op {op!r}", "available": list(OPS)}, p)
|
||||
try:
|
||||
return _tee(fn(p), p)
|
||||
except Exception as e: # noqa: BLE001
|
||||
return _tee({"ok": False, "error": str(e), "traceback": traceback.format_exc()}, p)
|
||||
|
||||
|
||||
def _tee(result: dict, p: dict) -> str:
|
||||
txt = json.dumps(result)
|
||||
try:
|
||||
if unreal is not None:
|
||||
sd = unreal.Paths.project_saved_dir() + "MCP/"
|
||||
os.makedirs(sd, exist_ok=True)
|
||||
rid = p.get("__rid") or "last"
|
||||
with open(sd + "last.json", "w", encoding="utf-8") as f:
|
||||
f.write(txt)
|
||||
if rid != "last":
|
||||
with open(sd + f"{rid}.json", "w", encoding="utf-8") as f:
|
||||
f.write(txt)
|
||||
unreal.log("[MCP-NIAGARA] " + txt[:1500])
|
||||
except Exception:
|
||||
pass
|
||||
return txt
|
||||
Reference in New Issue
Block a user