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Ilya d0bd47935a docs: mark plan complete and add screenshot to README

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

2026-07-02 23:27:09 +02:00

README.md

docs: mark plan complete and add screenshot to README

2026-07-02 23:27:09 +02:00

README.md

Pipeline Network Diagram Editor — Implementation Plan

A desktop diagram editor for drawing pipeline networks (water lines, power lines, gas, etc.), built with PyQt6 on the QGraphicsView / QGraphicsScene framework.

Tool selection (research outcome)

Candidate	Verdict
QGraphicsView framework (chosen)	Maximum control over custom SVG nodes, typed ports, orthogonal grid routing, arc crossings, flow animation. Mature, high item-count performance.
QtNodes (paceholder/nodeeditor)	Dataflow-centric, fixed node visuals, v3 breaking API — poor fit for grid-routed pipeline networks.
QuickQanava (QML)	Modern but connection routing in QML is the hard part; less control over orthogonal/arc routing.

Bindings: PyQt6 6.10 (apt, works with Python 3.14). Tests: pytest + pytest-qt, headless via QT_QPA_PLATFORM=offscreen.

Sources:

Phase 0 — Project scaffolding

Repo layout, requirements.txt, README.md, .gitignore
pipeline_editor package skeleton + __main__ entry point
pytest config + headless conftest (QApplication fixture)

Phase 1 — Domain model (no UI)

PropertyType enum: string, int, float, bool, enum, color, catalogue_item, catalogue_items, value_list
Property + PropertyGroup (grouped, editable/readonly, validation)
Catalogue / CatalogueItem registry
PortRelation registry (water/power/gas...) with color schemes + compatibility rules
Port (id, name, relation, side/offset, direction)
NodeModel, EdgeModel (ids, geometry, style, property groups)
DiagramDocument — holds nodes/edges, emits change signals
JSON serialization / deserialization (round-trip)

Phase 2 — Node library (feature #1)

Bundled SVG node graphics (pump, tank, valve, junction, source, sink, transformer…)
NodeTemplate = SVG + port configuration, organized into groups
Left dock NodePanel: grouped tree with vector previews
Drag-and-drop node template → canvas creates a node

Phase 3 — Canvas, scene & nodes

CanvasView: zoom (wheel), pan, fit-to-view, rubber-band select
Grid background (dots/lines), configurable size, snap-to-grid
NodeItem: renders SVG, movable, selectable, edges follow on move
Multi-select move, delete

Phase 4 — Ports & edges (features #2, #3, #5)

Focused node reveals PortItem handles
Port relation coloring + connection-compatibility feedback
Drag from port → other node's port (or self) creates an edge
Orthogonal routing along rectangular grid
Config option: draw arc at line intersections/crossings
EdgeItem styles: line style, head/tail decorations (arrow, circle, diamond, none)

Phase 5 — Property panel (feature #4)

Right dock PropertyPanel: grouped property editors
Editor widgets per type (string/int/float/bool/enum/color/catalogue/list)
Two-way binding: edit → model → view refresh
Geometry/title (presentation) group + physics group (length, diameter, flow rate, flow type)

Phase 6 — Mock calculation & flow animation

FlowSolver: mock flow distribution across edges (conservation-ish heuristic)
Per-edge flow value + direction
FlowAnimator: animate direction (marching dashes) and volume (speed/width)
Play/pause/stop controls

Phase 7 — Editing UX & configuration (added features)

Undo/redo via QUndoStack (add/move/delete/connect/edit)
Copy / paste / duplicate / delete
Save / Open / New document (JSON)
Export canvas to PNG / SVG
Config dialog: grid size, snap, arc-on-crossing, color scheme, animation speed
Multiple color schemes (light/dark + relation palettes)
Toolbar + menus + status bar + keyboard shortcuts

Phase 8 — Tests (typical scenarios)

Model: properties, catalogue, relations, serialization round-trip
Routing: orthogonal path + arc-crossing generation
Flow solver: conservation & direction on a small network
Scene: create node via drop, connect ports, move node moves edge, delete cascades
Property panel: edit propagates to model
Undo/redo of add/move/connect/delete

Phase 9 — Polish

README with run/test instructions and screenshots
Final pass: lint, docstrings, sample document