HAPI System Overview

Purpose

This note defines what HAPI is and how the foundation concepts fit together.

Source Priority

HAPI User Manual.pdf
HAPI Quick Start Guide.pdf
FeatureCatalogue.json
GlobalConfiguration.json
Old implementation Markdown notes

Definition

HAPI stands for HyD Automated Plotting Interface. It is a collection of Dynamo scripts for Autodesk Civil 3D that supports survey data exchange, plan drafting, plan production, and Existing Conditions Modelling (ECM).

HAPI is not only a plotting tool. It is a structured Civil 3D workflow built around standardised survey records, Point Codes, Feature Codes, Style Codes, object catalogues, and drafting configuration.

Main Workflow Families

Workflow Family	Purpose	Typical Outputs
Data Exchange	Import, export, and migrate survey data.	COGO Points, Feature Lines, blocks, point data files.
Drafting Aids	Improve drawing clarity and manage presentation.	Spot text visibility changes, LIC basemap overlays, topographic patterns.
Plan Production	Prepare layout-level drawing outputs.	Grid references, legends, title block support.
ECM Modelling	Convert 2D survey drawings into ECM deliverables.	Standalone ECM objects, linear ECM objects, stair tread objects.

Script Directory Model

Directory	Purpose
`HAPI-2D`	Survey data exchange and plan drafting scripts.
`HAPI-ECM`	BIM modelling and Existing Conditions Modelling scripts.

Key Foundation Concepts

Concept	Role
Point_Code	Field-data descriptor controlling how surveyed records are interpreted.
Feature_Code	Primary identifier for the surveyed feature.
Feature_Type	Mathematical routing channel: `1POINT`, `2POINT`, `LINEAR`, or `POLYGON`.
Style_Code	ECM descriptor defining physical appearance of real-world objects.
Feature_Catalogue	Central rulebook for routing, drafting behaviour, block references, styles, and object availability.
Global_Configuration	Project-wide defaults and mathematical thresholds.

Conceptual Workflow

Point Data / Drawing Entity
        ↓
Raw Description
        ↓
Point Code + optional Style Code
        ↓
Feature Code resolution
        ↓
Feature Catalogue lookup
        ↓
Feature Type routing
        ↓
Civil 3D drafting object / ECM object

Positioning of Obsidian

Obsidian is the knowledge-management layer. It should organise, link, and preserve HAPI logic, but it does not execute the HAPI automation itself.

Open Questions

Confirm whether future HAPI-NxtGen documentation should use the same script family names as the Dynamo-era manual, or introduce separate names for PythonNet3/C# modules.