archit-app 0.3.1

A general-purpose, extensible floorplan library for architects and developers.

A general-purpose, extensible Python library for architectural floorplan design and analysis.

pip install archit-app

---

Overview

archit_app provides a clean, layered data model for working with architectural floorplans in Python. It supports non-Manhattan shapes, curve walls, multi-level buildings, and exports to SVG, DXF, GeoJSON, and a canonical JSON format — all built on immutable, type-safe objects.

Key features:

• Geometry primitives with coordinate system (CRS) tagging — mixing spaces raises an error immediately
• Linear primitives — Segment2D (finite directed segment), Ray2D (half-line), Line2D (infinite line with parallel_offset, side_of, intersect), Polyline2D (ordered point sequence with segments(), bbox(), close(), to_polygon(), intersections())
• CoordinateConverter — graph-based multi-CRS path-finding; Point2D.to(target, conv); build_default_converter() for screen/image/world viewports
• Full NURBS evaluator — NURBSCurve uses the Cox–de Boor algorithm (exact rational evaluation, not linear interpolation); clamped_uniform() factory for smooth curves through endpoints; supports exact conic sections via rational weights
• Architectural elements: walls (straight, arc, spline), rooms, openings (doors/windows), columns, staircases, slabs, ramps, elevators, beams, furniture (20 categories, 18 named factories — sofa, beds, tables, desk, bathtub, toilet, sink, etc.), annotations (TextAnnotation with room-label factory, DimensionLine with auto-computed labels, SectionMark with view-direction arrows)
• Wall joining — miter_join(), butt_join(), join_walls() for clean corner geometry
• Structural grid — named axes (A–H, 1–8), intersection queries, and point snapping
• Multi-level building structure: Level → Building, with elevators and a grid attached at building level
• Land parcel model — GPS coordinates, setbacks, buildable envelope, and an AI-agent context hook; Land.minimal() for orientation-only use; SiteContext is a backward-compatible alias for Land
• Spatial analysis (archit_app.analysis):
  • Room adjacency graph and connected components (networkx)
  • Egress path finding and compliance reporting
  • Area program validation against design targets
  • Zoning compliance checker (FAR, lot coverage, height, setbacks)
  • Daylighting and solar orientation report per room
  • Isovist (visibility polygon) from any viewpoint
• I/O: JSON (fully round-trippable), SVG, GeoJSON, DXF round-trip (read + write, optional), IFC 4.x export (optional), PNG raster (Pillow, optional), PDF (reportlab, multi-page, optional)
• Layer registry — Layer model with color, visibility, and lock state; Building.add_layer() / is_layer_visible(); SVG/PDF/PNG renderers honour visible_layers filter; material-linked fill colours in SVG output
• Unit conversion (archit_app.units) — to_feet, from_feet, to_inches, from_inches, to_mm, from_mm, to_cm, from_cm; parse_dimension() accepts "12'-6\"", "3800mm", "10ft", "36\"", or bare floats (meters)
• Element transform utilities — copy_element(el, dx, dy), mirror_element(el, axis_x=…, axis_y=…), array_element(el, count, dx, dy) — all return new elements with fresh UUIDs
• Building validation — Building.validate() → ValidationReport with errors, warnings, and has_errors; Building.to_agent_context() for AI-agent handoff; Building.duplicate_level(src, new_index, new_elevation)
• GeoJSON import — level_from_geojson() / level_from_geojson_str() for full round-trip
• Level spatial index — Level.spatial_index() returns a Shapely STRtree over all spatially-aware elements for fast spatial queries
• Plugin registry for extending the library without touching core code
• Immutable Pydantic models throughout — every "mutation" returns a new object

---

Installation

pip install archit-app

For DXF and SVG export support:

pip install "archit-app[io]"

For IFC export (open BIM standard — Revit, ArchiCAD, FreeCAD compatible):

pip install "archit-app[ifc]"

For PNG raster export (Pillow):

pip install "archit-app[image]"

For PDF export (reportlab):

pip install "archit-app[pdf]"

For graph-based analysis (room adjacency, egress path-finding):

pip install "archit-app[analysis]"

For all optional dependencies:

pip install "archit-app[io,ifc,image,pdf,analysis]"

Requirements: Python 3.11+, pydantic ≥ 2.0, shapely ≥ 2.0, numpy ≥ 1.26

---

Quick Start

from archit_app import (
    Wall, Room, Level, Building, BuildingMetadata,
    Opening, Column, Point2D, Polygon2D, WORLD,
)

# 1. Create a room
boundary = Polygon2D.rectangle(0, 0, 6, 4, crs=WORLD)
living_room = Room(boundary=boundary, name="Living Room", program="living")

# 2. Create walls
north_wall = Wall.straight(0, 4, 6, 4, thickness=0.2, height=3.0)
south_wall = Wall.straight(0, 0, 6, 0, thickness=0.2, height=3.0)
west_wall  = Wall.straight(0, 0, 0, 4, thickness=0.2, height=3.0)

# Add a door to the west wall
door = Opening.door(x=0, y=1.5, width=0.9, height=2.1)
west_wall = west_wall.add_opening(door)

# 3. Add a structural column
col = Column.rectangular(x=2.8, y=1.8, width=0.3, depth=0.3, height=3.0)

# 4. Assemble a level
ground = (
    Level(index=0, elevation=0.0, floor_height=3.0, name="Ground Floor")
    .add_room(living_room)
    .add_wall(north_wall)
    .add_wall(south_wall)
    .add_wall(west_wall)
    .add_column(col)
)

# 5. Build the building
building = (
    Building()
    .with_metadata(name="My House", architect="A. Architect")
    .add_level(ground)
)

print(building)
# Building(name='My House', levels=1, gross_area=24.0m²)

Export to SVG

from archit_app.io.svg import level_to_svg, save_level_svg

svg_str = level_to_svg(ground, pixels_per_meter=50)
save_level_svg(ground, "ground_floor.svg", pixels_per_meter=50)

Export to JSON and reload

from archit_app.io.json_schema import save_building, load_building

save_building(building, "my_house.archit_app.json")
restored = load_building("my_house.archit_app.json")

Export to GeoJSON

from archit_app.io.geojson import level_to_geojson
import json

fc = level_to_geojson(ground)
print(json.dumps(fc, indent=2))

Define a land parcel and get agent context

from archit_app import Land, Setbacks, ZoningInfo, Building

# 1. Define the parcel from GPS coordinates
land = Land.from_latlon([
    (37.7749, -122.4194),
    (37.7750, -122.4194),
    (37.7750, -122.4183),
    (37.7749, -122.4183),
], address="123 Main St, San Francisco, CA")

print(f"Lot area: {land.area_m2:.1f} m²")

# 2. Export a context dict — pass this to an AI agent to get zoning info
context = land.to_agent_context()
# {
#   "address": "123 Main St, San Francisco, CA",
#   "area_m2": 598.1,
#   "latlon_coords": [...],
#   "centroid_latlon": [...],
#   ...
# }

# 3. Enrich with zoning (manually or from an agent response)
land = (
    land
    .with_zoning(ZoningInfo(
        zone_code="RH-2",
        max_height_m=10.0,
        max_far=1.8,
        max_lot_coverage=0.6,
        allowed_uses=("residential",),
        source="SF Planning Code §207",
    ))
    .with_setbacks(Setbacks(front=3.0, back=6.0, left=1.5, right=1.5))
)

print(f"Buildable area: {land.buildable_area_m2:.1f} m²")
print(f"Max floor area: {land.max_floor_area_m2:.1f} m²")

# 4. Attach the land to a building
building = Building().with_land(land)

DXF round-trip (read + write)

# Requires: pip install "archit-app[io]"
from archit_app.io.dxf import (
    save_building_dxf, building_from_dxf,
    save_level_dxf, level_from_dxf,
)

# Export
save_building_dxf(building, "my_house.dxf")

# Import back — auto-detects archit-app's FP_* layer convention
restored = building_from_dxf("my_house.dxf")

# Import a single level, override defaults
level = level_from_dxf("floor_plan.dxf", wall_height=3.5, wall_thickness=0.25)

# Generic DXF with custom layer names
level = level_from_dxf(
    "autocad_drawing.dxf",
    layer_mapping={"A-WALL": "walls", "A-FLOR-PATT": "rooms"},
)

Recognised element types in layer_mapping: "walls", "rooms", "openings", "columns".

Export to PNG (raster)

# Requires: pip install "archit-app[image]"
from archit_app.io.image import save_level_png, save_building_pngs, level_to_png_bytes

# Single level at 100 px/m, 150 DPI
save_level_png(ground, "ground_floor.png", pixels_per_meter=100, dpi=150)

# All levels — one PNG per level — into a directory
save_building_pngs(building, "output/", pixels_per_meter=100, dpi=150)

# Raw bytes (e.g. for HTTP response or in-memory processing)
png_bytes = level_to_png_bytes(ground, pixels_per_meter=100)

Renders rooms, walls, columns, openings, room labels with area, and a 1 m scale bar. Uses 2× supersampling for clean anti-aliased edges at any scale.

Export to PDF

# Requires: pip install "archit-app[pdf]"
from archit_app.io.pdf import save_level_pdf, save_building_pdf, level_to_pdf_bytes

# Single level — auto-selects landscape if drawing is wider than tall
save_level_pdf(ground, "ground_floor.pdf", paper_size="A3")

# All levels in one multi-page PDF (one page per level)
save_building_pdf(building, "my_house.pdf", paper_size="A3")

# Force portrait, A4
save_level_pdf(ground, "ground_portrait.pdf", paper_size="A4", landscape=False)

# Raw bytes
pdf_bytes = level_to_pdf_bytes(ground, paper_size="A3")

Supported paper sizes: "A1", "A2", "A3" (default), "A4", "letter". Each level is centred and scaled to fill the page.

Export to IFC 4.x

# Requires: pip install "archit-app[ifc]"
from archit_app.io.ifc import building_to_ifc, save_building_ifc

# Get the ifcopenshell model object (for further manipulation)
model = building_to_ifc(building)
print(model.by_type("IfcWall"))       # list all exported walls
print(model.by_type("IfcSpace"))      # list all exported rooms
model.write("my_house.ifc")           # write to disk

# Or use the one-line convenience function
save_building_ifc(building, "my_house.ifc")

Exported to IFC: walls (IfcWall), rooms (IfcSpace), doors/windows (IfcDoor/IfcWindow), columns (IfcColumn), slabs (IfcSlab), staircases (IfcStair), ramps (IfcRamp), beams (IfcBeam), furniture (IfcFurnishingElement), elevators (IfcTransportElement) — all under the full IfcProject → IfcSite → IfcBuilding → IfcBuildingStorey hierarchy. The IFC file can be opened in Revit, ArchiCAD, FreeCAD, and any other IFC 4-compliant viewer.

# Import an IFC file back into archit_app
from archit_app.io.ifc import building_from_ifc, level_from_ifc

building = building_from_ifc("my_house.ifc")
print(len(building.levels))          # number of floors
print(len(building.levels[0].walls)) # walls on ground floor

# Import just one storey
ground = level_from_ifc("my_house.ifc", storey_index=0)

Imported element types: IfcWall → Wall, IfcSpace → Room, IfcDoor/IfcWindow → Opening, IfcColumn → Column, IfcSlab → Slab, IfcStair → Staircase, IfcRamp → Ramp, IfcBeam → Beam, IfcFurnishingElement → Furniture, IfcTransportElement → Elevator.

Vertical circulation and structural elements

import math
from archit_app import (
    Staircase, Slab, Ramp, Elevator, ElevatorDoor,
    Beam, BeamSection, Level, Building,
)

# Staircase — 12 risers connecting ground floor to first floor
stair = Staircase.straight(
    x=6, y=0, width=1.2, rise_count=12,
    rise_height=0.175, run_depth=0.28,
    bottom_level_index=0, top_level_index=1,
)
print(f"Total rise: {stair.total_rise:.2f} m")   # 2.10 m

# Slab — 200 mm concrete floor deck
slab = Slab.rectangular(x=0, y=0, width=10, depth=8,
                         thickness=0.2, elevation=0.0)

# Ramp — 1:12 accessible ramp (≈ 4.8° slope)
ramp = Ramp.straight(x=0, y=0, width=1.5, length=3.6,
                      slope_angle=math.radians(4.76),
                      bottom_level_index=0, top_level_index=1)

# Elevator — 1.1 × 1.4 m cab, 0 → 3
elevator = Elevator.rectangular(x=8, y=0, cab_width=1.1, cab_depth=1.4,
                                 bottom_level_index=0, top_level_index=3)

# Structural beam — 300 mm wide, 500 mm deep, top at 3.5 m
beam = Beam.straight(x1=0, y1=0, x2=6, y2=0,
                     width=0.3, depth=0.5, elevation=3.5,
                     section=BeamSection.RECTANGULAR)
print(f"Span: {beam.span:.1f} m, soffit: {beam.soffit_elevation:.2f} m")

# Assemble
ground = (
    Level(index=0, elevation=0.0, floor_height=3.0)
    .add_staircase(stair)
    .add_slab(slab)
    .add_ramp(ramp)
    .add_beam(beam)
)
building = Building().add_level(ground).add_elevator(elevator)

Structural grid and wall joining

from archit_app import StructuralGrid, Wall, join_walls, miter_join, Point2D, WORLD

# Create a 3 × 3 regular grid at 6 m spacing
grid = StructuralGrid.regular(
    x_spacing=6.0, y_spacing=6.0,
    x_count=3, y_count=3,
)

# Query intersections
pt = grid.intersection("2", "B")   # grid point at column 2, row B
print(pt)                           # Point2D(x=6.0, y=6.0, ...)

# Snap a point to the nearest grid intersection
p = Point2D(x=5.95, y=6.1, crs=WORLD)
snapped = grid.snap_to_grid(p, tolerance=0.2)

# Attach grid to a building
building = Building().with_grid(grid)

# Clean up wall corners with miter joins
wall_h = Wall.straight(0, 0, 5, 0, thickness=0.2, height=3.0)
wall_v = Wall.straight(5, 0, 5, 4, thickness=0.2, height=3.0)

wall_h_trimmed, wall_v_trimmed = miter_join(wall_h, wall_v)

# Or join a whole room's worth of walls at once
walls = [
    Wall.straight(0, 0, 5, 0, thickness=0.2, height=3.0),
    Wall.straight(5, 0, 5, 4, thickness=0.2, height=3.0),
    Wall.straight(5, 4, 0, 4, thickness=0.2, height=3.0),
    Wall.straight(0, 4, 0, 0, thickness=0.2, height=3.0),
]
joined_walls = join_walls(walls)

NURBS curved walls

import math
from archit_app import Point2D, WORLD
from archit_app.geometry.curve import NURBSCurve
from archit_app import Wall

# Smooth cubic curve through 5 control points (clamped — passes through endpoints)
ctrl = (
    Point2D(0, 0, crs=WORLD),
    Point2D(1, 2, crs=WORLD),
    Point2D(2, 0, crs=WORLD),
    Point2D(3, 2, crs=WORLD),
    Point2D(4, 0, crs=WORLD),
)
curve = NURBSCurve.clamped_uniform(ctrl, degree=3)

# Sample 64 points along the curve (exact, not linear interpolation)
polyline = curve.to_polyline(resolution=64)
print(f"Arc length ≈ {curve.length():.3f} m")

# Exact quarter-circle arc via rational NURBS (w = cos(π/4) on the middle point)
w = math.cos(math.pi / 4)
circle_pts = (
    Point2D(1, 0, crs=WORLD),
    Point2D(1, 1, crs=WORLD),
    Point2D(0, 1, crs=WORLD),
)
quarter_circle = NURBSCurve.clamped_uniform(circle_pts, degree=2, weights=(1.0, w, 1.0))

# Use a NURBS curve as wall geometry
wall = Wall(geometry=curve.to_polygon(resolution=32), thickness=0.2, height=3.0)

Coordinate conversion

from archit_app import build_default_converter, SCREEN, WORLD, IMAGE, Point2D

# Build the standard viewport converter (800×600 canvas, 50 px/m)
conv = build_default_converter(
    viewport_height_px=600.0,
    pixels_per_meter=50.0,
    canvas_origin_world=(0.0, 0.0),   # world coords of canvas bottom-left
)

# Convert a screen click to a world position
screen_click = Point2D(x=400.0, y=300.0, crs=SCREEN)
world_pos = screen_click.to(WORLD, conv)
print(world_pos)   # Point2D(x=8.0, y=6.0, crs='world')

# Round-trip back to screen
back = world_pos.to(SCREEN, conv)

# IMAGE → WORLD works too — resolved via BFS through SCREEN
import numpy as np
world_pts = conv.convert(np.array([[400.0, 300.0]]), IMAGE, WORLD)

# Extend with custom spaces: register any transform and multi-hop paths
# are found automatically
from archit_app import CoordinateConverter, WGS84
conv.register(WORLD, WGS84, some_georeference_transform)
# Now IMAGE → WGS84 resolves as IMAGE → SCREEN → WORLD → WGS84

Layer visibility and material-linked rendering

from archit_app import Building, Level, Wall, Room, Polygon2D, WORLD
from archit_app.building.layer import Layer
from archit_app.io.svg import level_to_svg

# 1. Register layers on the building
building = (
    Building()
    .add_layer(Layer(name="structure", color_hex="#808080", visible=True))
    .add_layer(Layer(name="finishes",  color_hex="#C8A080", visible=False))
    .add_level(ground)
)

# 2. SVG only renders elements whose layer is in the visible set
svg = level_to_svg(ground, visible_layers={"structure"})   # "finishes" hidden

# 3. Material-linked colours in SVG
from archit_app.materials import default_library
svg = level_to_svg(ground, material_library=default_library)
# Walls use their material's colour; falls back to default palette

Unit conversion

from archit_app.units import (
    to_feet, from_feet, to_inches, from_inches,
    to_mm, from_mm, to_cm, from_cm,
    parse_dimension,
)

# Metric ↔ Imperial
print(to_feet(3.048))        # 10.0
print(from_feet(10.0))       # 3.048
print(to_inches(0.0254))     # 1.0
print(to_mm(1.0))            # 1000.0

# parse_dimension accepts mixed strings
print(parse_dimension("12'-6\""))   # 3.81  (meters)
print(parse_dimension("3800mm"))    # 3.8
print(parse_dimension("10ft"))      # 3.048
print(parse_dimension("36\""))      # 0.9144
print(parse_dimension("3.5"))       # 3.5   (bare float → meters)

Element transform utilities

from archit_app.elements.transform_utils import copy_element, mirror_element, array_element
from archit_app import Wall

wall = Wall.straight(0, 0, 5, 0, thickness=0.2, height=3.0)

# Translate — new element with fresh UUID
wall2 = copy_element(wall, dx=0, dy=3.0)

# Mirror about y = 2.5
mirrored = mirror_element(wall, axis_y=2.5)

# Linear array — returns [original, copy1, copy2, …]
row = array_element(wall, count=4, dx=6.0, dy=0)
# produces 4 walls spaced 6 m apart

Building validation and agent context

from archit_app import Building

building = Building().add_level(ground)

# Validate for common issues
report = building.validate()
if report.has_errors:
    for issue in report.issues:
        print(f"[{issue.severity.upper()}] {issue.message}")

# Export a flat dict for AI-agent handoffs
ctx = building.to_agent_context()
# {
#   "name": "My House",
#   "level_count": 1,
#   "total_gross_area_m2": 24.0,
#   "levels": [...],
#   ...
# }

# Duplicate a level (fresh UUIDs for all elements)
building2 = building.duplicate_level(src_index=0, new_index=1, new_elevation=3.0)

Spatial index

# Requires: pip install shapely
from shapely.geometry import box

tree, elements = ground.spatial_index()

# Fast rectangular query — returns matching elements
hits = tree.query(box(0, 0, 3, 3))
nearby = [elements[i] for i in hits]
print([type(e).__name__ for e in nearby])   # ["Wall", "Room", ...]

GeoJSON import

from archit_app.io.geojson import (
    level_to_geojson, level_from_geojson,
    level_to_geojson_str, level_from_geojson_str,
)

# Export
fc = level_to_geojson(ground)

# Import back — full round-trip
restored = level_from_geojson(fc, index=0, elevation=0.0, floor_height=3.0)
assert len(restored.rooms) == len(ground.rooms)

# From/to JSON string
json_str  = level_to_geojson_str(ground)
restored2 = level_from_geojson_str(json_str)

Spatial analysis

from archit_app.analysis.topology import build_adjacency_graph, connected_components
from archit_app.analysis.circulation import egress_report
from archit_app.analysis.area import area_by_program, area_report, AreaTarget
from archit_app.analysis.compliance import check_compliance
from archit_app.analysis.daylighting import daylight_report
from archit_app.analysis.visibility import compute_isovist, mutual_visibility

# --- Room adjacency graph (requires pip install archit-app[analysis]) ---
G = build_adjacency_graph(ground)
# G.nodes[room.id] = {room, centroid, area_m2, program, level_index}
# G.edges[a, b]    = {shared_length_m, distance_m, opening_ids}

components = connected_components(G)   # list of connected room groups

# --- Egress compliance ---
exit_ids = {stair_room.id, lobby_room.id}
report = egress_report(ground, exit_ids=exit_ids, max_distance_m=30.0)
# [{"room_id", "egress_distance_m", "path", "compliant"}, ...]

# --- Area program validation ---
totals = area_by_program(building)
# {"bedroom": 32.0, "kitchen": 8.0, ...}

results = area_report(building, targets=[
    AreaTarget(program="bedroom", target_m2=30.0, tolerance_fraction=0.10),
    AreaTarget(program="kitchen", target_m2=10.0),
])
# [ProgramAreaResult(program, actual_m2, target_m2, deviation_fraction, compliant), ...]

# --- Zoning compliance ---
compliance = check_compliance(building, land)
print(compliance.summary())
# Compliance report — PASS
#   [PASS] Floor Area Ratio (FAR): 0.16  (limit: 0.5)
#   [PASS] Building height: 3.0 m  (limit: 10.0 m)
#   [PASS] Footprint within lot boundary: yes
#   [PASS] Footprint within setback envelope: yes

# --- Daylighting ---
daylight = daylight_report(ground, north_angle_deg=15.0)
for r in daylight:
    print(f"{r.room_name}: WFR={r.window_to_floor_ratio:.2f}, "
          f"solar_score={r.avg_solar_score:.2f}")

# --- Isovist (visibility polygon) ---
from archit_app import Point2D, WORLD
vp = Point2D(x=5.0, y=3.0, crs=WORLD)
result = compute_isovist(vp, ground, resolution=360, max_range=20.0)
print(f"Visible area: {result.area_m2:.1f} m²")

# Line-of-sight check
can_see = mutual_visibility(Point2D(x=2, y=2, crs=WORLD),
                             Point2D(x=8, y=2, crs=WORLD), ground)

---

Coordinate System

archit_app uses a Y-up, meters world coordinate system — the standard for architecture. Screen and image layers are Y-down; the library handles the flip at export time so your geometry code never sees it.

Space	Origin	Y direction	Unit	Use
WORLD	site datum	up	meters	all architectural geometry
SCREEN	top-left	down	pixels	rendering, UI events
IMAGE	top-left	down	pixels	raster images, panoramas
WGS84	lat/lon	up	meters	GIS / site georeferencing

Every Point2D and Vector2D carries its CRS. Arithmetic between mismatched spaces raises CRSMismatchError immediately.

---

Architecture

The library is structured in layers:

archit_app/
├── geometry/     Layer 1 — CRS, points, vectors, transforms, polygons, curves,
│                            Segment2D/Ray2D/Line2D/Polyline2D, CoordinateConverter
├── elements/     Layer 2 — Wall, Room, Opening, Column, Staircase, Slab,
│                            Ramp, Elevator, Beam, Furniture, TextAnnotation,
│                            DimensionLine, SectionMark, wall_join utilities
├── building/     Layer 3 — Land, Setbacks, ZoningInfo, Level, Building,
│                            BuildingMetadata, StructuralGrid, Layer registry,
│                            ValidationReport, duplicate_level, to_agent_context,
│                            spatial_index
├── analysis/     Layer 6 — topology, circulation, area, compliance,
│                            daylighting, visibility
├── io/           Layer 5 — JSON, SVG, GeoJSON (read+write), DXF (read+write),
│                            IFC 4.x, PNG, PDF
├── core/         Registry — plugin/extension system
├── units.py      Unit conversion — parse_dimension, to/from feet/inches/mm/cm
└── utils/        Shared helpers; element transform utilities

All models are immutable. Every "mutation" method (e.g. level.add_wall(w), wall.add_opening(o)) returns a new object.

---

Documentation

Full API reference and guides are in the docs/ directory:

• Getting Started
• Core Concepts
• API Reference — Geometry
• API Reference — Elements
• API Reference — Building
• API Reference — I/O
• API Reference — Registry
• Contributing

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Roadmap

Phase	Status	Description
Layer 1 — Geometry	Done	CRS, Point, Vector, BBox, Polygon, Curve, Transform, Segment2D/Ray2D/Line2D/Polyline2D
Layer 2 — Elements (core)	Done	Wall, Room, Opening, Column, Furniture, TextAnnotation, DimensionLine, SectionMark
Layer 2 — Elements (circulation/structural)	Done	Staircase, Ramp, Elevator, Slab, Beam, StructuralGrid, wall joining
Layer 3 — Building	Done	Level, Building, Land, Setbacks, ZoningInfo
Layer 5 — I/O	Done	JSON, SVG, GeoJSON, DXF (read+write), IFC 4.x, PNG, PDF
Layer 6 — Analysis	Done	Topology graph, egress, area validation, zoning compliance, daylighting, isovist
CoordinateConverter	Done	Graph-based multi-CRS path-finding; Point2D.to()
NURBS evaluator	Done	Cox–de Boor; clamped_uniform() factory; exact conic sections
Layer 4 — App infrastructure	Done	ElementQuery (select/filter), History (undo/redo), Viewport (view state)
Material registry	Done	Material, MaterialLibrary, 12 builtin presets, default_library
Level / Building utilities	Done	Level.replace_element(), Building.stats() → BuildingStats
Analysis completeness	Done	Accessibility checker, room-from-walls auto-detection
JSON migration	Done	migrate_json() — upgrades 0.1.0 → 0.2.0 snapshots
I/O completeness	Done	SVG/PDF/PNG render furniture, beams, ramps, annotations, dimensions, section marks, staircases, slabs, archways; material-linked SVG fill colours; DXF annotation/dimension/section-mark layers; IFC extended export (ramp, beam, furniture, elevator)
GeoJSON round-trip	Done	level_from_geojson() / level_from_geojson_str() import
IFC round-trip	Done	building_from_ifc() / level_from_ifc() import; full element type coverage
Layer registry	Done	Layer model; building-level layer registry; renderer visibility filtering
Unit conversion	Done	parse_dimension(), to_feet/inches/mm/cm, from_feet/inches/mm/cm
Element transforms	Done	copy_element, mirror_element, array_element
Building utilities	Done	validate() → ValidationReport, to_agent_context(), duplicate_level()
Spatial index	Done	Level.spatial_index() → Shapely STRtree over all elements

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Contributing

Contributions are welcome. See CONTRIBUTING for setup instructions and coding standards.

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License

MIT