isaac-sim · qianl-nv · Jun 16, 2026 · Jun 16, 2026 · Jun 16, 2026 · Jun 16, 2026
@@ -9,7 +9,7 @@
 from pathlib import Path
 from typing import TYPE_CHECKING, Any, Self
 
-from pydantic import BaseModel, Field, SerializeAsAny, field_validator, model_validator
+from pydantic import BaseModel, Field, SerializeAsAny, ValidationInfo, field_validator, model_validator
 
 from isaaclab_arena.assets.registries import TaskRegistry
 from isaaclab_arena.environments.arena_env_graph_types import (
@@ -158,8 +158,10 @@ class ArenaEnvInitialGraphSpec(ArenaEnvGraphSpecBase):
     initial_state_spec: ArenaEnvGraphStateSpec
 
     @model_validator(mode="after")
-    def validate(self) -> Self:
+    def validate(self, info: ValidationInfo) -> Self:
         """Check unique IDs, constraint references, and spatial constraint shapes."""
+        if info.context and info.context.get("skip_registry"):
+            return self
         assert_unique_ids(self.nodes, [], [self.initial_state_spec])
         assert_constraint_references(self.nodes, [self.initial_state_spec])
         assert_spatial_constraint_shapes([self.initial_state_spec])

@@ -16,7 +16,7 @@
 from enum import Enum
 from typing import Any
 
-from pydantic import BaseModel, Field, field_validator, model_validator
+from pydantic import BaseModel, Field, ValidationInfo, field_validator, model_validator
 
 from isaaclab_arena.assets.object_type import ObjectType
 from isaaclab_arena.assets.registries import ObjectRelationLibraryRegistry, TaskRegistry
@@ -115,7 +115,9 @@ class TaskSpec(BaseModel):
 
     @field_validator("kind")
     @classmethod
-    def _validate_registered_task_type(cls, value: str) -> str:
+    def _validate_registered_task_type(cls, value: str, info: ValidationInfo) -> str:
+        if info.context and info.context.get("skip_registry"):
+            return value
         registry = TaskRegistry()
         assert registry.is_registered(value), f"Unknown task kind '{value}'"
         return value
@@ -169,7 +171,9 @@ class SpatialRelationSpec(BaseModel):
     )
 
     @model_validator(mode="after")
-    def _validate_kind_and_arity(self) -> SpatialRelationSpec:
+    def _validate_kind_and_arity(self, info: ValidationInfo) -> SpatialRelationSpec:
+        if info.context and info.context.get("skip_registry"):
+            return self
         registry = ObjectRelationLibraryRegistry()
         assert registry.is_registered(self.kind), f"Unknown relation kind '{self.kind}'"
         relation_cls = registry.get_object_relation_by_name(self.kind)

@@ -17,9 +17,10 @@
 from isaaclab_arena_examples.agentic_environment_generation.review_gui.render.styles import DASHBOARD_CSS
 
 
-def render_dashboard_html(spec: ArenaEnvInitialGraphSpec) -> str:
+def render_dashboard_html(spec: ArenaEnvInitialGraphSpec, thumbnails: dict[str, bytes] | None = None) -> str:
     """Render the self-contained review dashboard HTML for ``spec``."""
     initial_state = spec.initial_state_spec
+    thumbnails = thumbnails or {}
     return f"""<!DOCTYPE html>
 <html lang="en">
 <head>
@@ -36,7 +37,7 @@ def render_dashboard_html(spec: ArenaEnvInitialGraphSpec) -> str:
 <main>
   <section class="panel nodes-panel">
     <h2>Nodes</h2>
-    <div class="node-grid">{render_node_cards(spec)}</div>
+    <div class="node-grid">{render_node_cards(spec, thumbnails)}</div>
   </section>
   <section class="panel graph-panel">
     <h2>Spatial graph <span class="muted">(initial state: <code>{html_lib.escape(initial_state.id)}</code>)</span></h2>

@@ -10,9 +10,7 @@
 
 from isaaclab_arena.environments.arena_env_graph_spec import ArenaEnvInitialGraphSpec
 from isaaclab_arena.environments.arena_env_graph_types import ArenaEnvGraphNodeSpec, ArenaEnvGraphStateSpec
-from isaaclab_arena_examples.agentic_environment_generation.review_gui.render.thumbnails import (
-    render_placeholder_thumbnail,
-)
+from isaaclab_arena_examples.agentic_environment_generation.review_gui.render.thumbnails import render_node_thumbnail
 
 
 def render_unary_constraints(state: ArenaEnvGraphStateSpec) -> str:
@@ -63,16 +61,17 @@ def render_tasks_table(spec: ArenaEnvInitialGraphSpec) -> str:
     )
 
 
-def render_node_cards(spec: ArenaEnvInitialGraphSpec) -> str:
+def render_node_cards(spec: ArenaEnvInitialGraphSpec, thumbnails: dict[str, bytes] | None = None) -> str:
     """Render one card per graph node for the dashboard nodes panel."""
-    return "\n".join(render_node_card(node) for node in spec.nodes)
+    thumbnails = thumbnails or {}
+    return "\n".join(render_node_card(node, thumbnails.get(node.id)) for node in spec.nodes)
 
 
-def render_node_card(node: ArenaEnvGraphNodeSpec) -> str:
-    """Render a single node card with placeholder thumbnail and YAML dump."""
+def render_node_card(node: ArenaEnvGraphNodeSpec, png_bytes: bytes | None = None) -> str:
+    """Render a single node card with USD snapshot or placeholder thumbnail and YAML dump."""
     node_dict = node.model_dump(mode="json", exclude_none=True)
     node_yaml = yaml.safe_dump(node_dict, sort_keys=False).rstrip()
-    thumb = render_placeholder_thumbnail(node)
+    thumb = render_node_thumbnail(node, png_bytes)
     return f"""<article class="node-card type-{html_lib.escape(node.type.value)}">
   {thumb}
   <div class="node-meta">

@@ -5,14 +5,22 @@
 
 from __future__ import annotations
 
+import base64
 import html as html_lib
 
 from isaaclab_arena.environments.arena_env_graph_types import ArenaEnvGraphNodeSpec
 
 
-# TODO(qianl): Replace placeholder thumbnails with sim-rendered snapshots .
-def render_placeholder_thumbnail(node: ArenaEnvGraphNodeSpec) -> str:
-    """Per-node placeholder thumbnail — two-letter initial."""
+def render_node_thumbnail(node: ArenaEnvGraphNodeSpec, png_bytes: bytes | None = None) -> str:
+    """Per-node thumbnail: USD capture if available, else two-letter placeholder."""
+    if png_bytes:
+        b64 = base64.b64encode(png_bytes).decode("ascii")
+        return (
+            '<div class="thumb thumb-rendered">'
+            f'<img src="data:image/png;base64,{b64}" alt="{html_lib.escape(node.name)} thumbnail">'
+            f'<span class="thumb-name">{html_lib.escape(node.name)}</span>'
+            "</div>"
+        )
     initial = (node.name[:2] if node.name else "?").upper()
     return f"""<div class="thumb">
     <span class="thumb-initial">{html_lib.escape(initial)}</span>