ASMBLR

DAG-based Representation for Symbolic Geometry (GeoLIPI, SySL, Migumi, and others).

ASMBLR provides a node-based programming interface for symbolic expressions. It allows you to build, manipulate, and evaluate directed acyclic graphs (DAGs) that represent geometric and material expressions.

Quick Start | Generating Node Files | API Reference

Features

• Node-based DAG construction - Build complex expressions by connecting nodes
• Auto-generated nodes - Automatically generates node wrappers for GeoLIPI, SySL, and Migumi symbols
• Bidirectional conversion - Convert between GeoLIPI expressions and ASMBLR DAGs
• Serialization - Save/load DAGs to/from JSON format
• Frontend export - Generate nodes.json for visual node editors

Installation

From source

cd asmblr
pip install -e .

Dependencies

Required:

• geolipi - Symbolic geometry library
• sysl - Symbolic shading language

Optional:

• migumi - Extended geometry primitives (nodes generated only if available)

Quick Start

1. Direct Node Instantiation

import asmblr.nodes as anode
import asmblr

# Create nodes directly
sphere = anode.Sphere3D(radius=1.5)
box = anode.Box3D(size=(2, 2, 2))
union = anode.Union(sphere, box)

# Evaluate to get the expression
union.evaluate()
result_expr = union.outputs['expr']
print(result_expr)  # Union(Sphere3D(1.5), Box3D((2, 2, 2)))

2. Convert GeoLIPI Expressions to ASMBLR DAGs

import asmblr
import geolipi.symbolic as gls

# Create a GeoLIPI expression
geolipi_expr = gls.Union(gls.Sphere3D(1.0), gls.Box3D((1, 1, 1)))

# Convert to ASMBLR DAG
asmblr_dag = asmblr.converter.convert_to_asmblr(geolipi_expr)

# Evaluate the DAG to recover the expression
asmblr_dag.evaluate()
recovered_expr = asmblr_dag.outputs['expr']

3. Building Complex DAGs with Connections

import asmblr.nodes as anode

# Create primitives
sphere1 = anode.Sphere3D(radius=0.8)
sphere2 = anode.Sphere3D(radius=0.6)
box = anode.Box3D(size=(0.5, 0.5, 0.5))

# Build the DAG
translated = anode.Translate3D(sphere2, translation=(1.0, 0.0, 0.0))
union = anode.Union(sphere1, translated)
final = anode.Difference(union, box)

# Evaluate
final.evaluate()
print(final.outputs['expr'])

4. Serialization

import json
from asmblr.base import BaseNode

# Serialize to dictionary
dag_dict = final.to_dict()

# Save to JSON file
with open("my_dag.json", "w") as f:
    json.dump(dag_dict, f, indent=2)

# Load from JSON file
with open("my_dag.json", "r") as f:
    loaded_dict = json.load(f)

# Reconstruct the DAG
restored_dag = BaseNode.from_dict(loaded_dict)

Node Discovery

import asmblr

# List all available nodes
all_nodes = asmblr.list_nodes()
print(f"Total nodes: {len(all_nodes)}")

# Search for specific nodes
sphere_nodes = asmblr.search_nodes("sphere")
material_nodes = asmblr.search_nodes("material")

# Inspect a node's inputs and outputs
asmblr.inspect_node(anode.Sphere3D)
# Output:
# Sphere3D
#   Inputs: [radius:float]
#   Outputs: ['expr']
#   Expression: Sphere3D

Generating Node Files

ASMBLR can auto-generate Python node files from symbolic libraries. Use this whenever the underlying libraries get updated to generate nodes corresponding to updated symbols.

# Generate all node files (GeoLIPI, SySL, Migumi if available)
python generate_nodes.py

# Force regenerate (overwrite existing)
python generate_nodes.py --force

# Generate specific libraries only
python generate_nodes.py --geolipi
python generate_nodes.py --sysl
python generate_nodes.py --migumi

Generated files are saved to asmblr/auto_nodes/.

Frontend JSON Export

Generate a nodes.json file for visual node editors:

python scripts/asmblr_frontend_json.py --out nodes.json

This creates a JSON file with node definitions including:

• Input/output socket definitions
• Control configurations (for non-expression parameters)
• Category metadata

Project Structure

asmblr/
├── asmblr/
│   ├── __init__.py          # Main exports
│   ├── base.py              # BaseNode, Connection, Socket classes
│   ├── expr_node.py         # GLNode base for expression nodes
│   ├── nodes.py             # Dynamic node access (anode.NodeName)
│   ├── converter.py         # GeoLIPI ↔ ASMBLR conversion
│   ├── serialize.py         # Serialization utilities
│   ├── simple_registry.py   # Node registry
│   ├── auto_loader.py       # Auto-generation of node files
│   ├── auto_nodes/          # Auto-generated node classes
│   │   ├── geolipi_nodes.py
│   │   ├── sysl_nodes.py
│   │   └── migumi_nodes.py
│   └── custom_nodes/        # Manually defined custom nodes
│       ├── custom_geolipi.py
│       └── custom_mxg.py
├── scripts/
│   ├── asmblr_frontend_json.py  # Frontend JSON generator
│   ├── examples.py              # Usage examples
│   └── test_serialization.py    # Serialization tests
├── generate_nodes.py        # Node generation CLI
└── README.md

Environment Variables

• ASMBLR_DISABLE_AUTO_LOAD=1 - Disable automatic node loading on import

API Reference

Core Classes

• BaseNode - Abstract base class for all DAG nodes
• GLNode - Base class for expression-wrapping nodes
• Connection - Represents a connection between node sockets
• InputSocket / OutputSocket - Node socket classes

Key Functions

• asmblr.list_nodes() - List all registered node names
• asmblr.search_nodes(pattern) - Search nodes by regex pattern
• asmblr.inspect_node(node) - Print node information
• asmblr.converter.convert_to_asmblr(expr) - Convert GeoLIPI expression to DAG

Node Registry

from asmblr import NODE_REGISTRY

# Access registered nodes
node_class = NODE_REGISTRY['Sphere3D']

# Register custom nodes
from asmblr import register_node

@register_node
class MyCustomNode(GLNode):
    ...

License

Research code - see repository license.