ROMGEO Demo Guide

The ROMGEO Demo Page at https://api.romgeo.ro/api/v1/demo.html is a modern web interface intended for geodesy specialists and field operators to convert ETRS89 geographic coordinates (EPSG:4258 – Latitude, Longitude, Altitude) into EPSG:3844 projected coordinates (Romania – STEREO70). This tool replaces and improves upon the legacy desktop app TransDAT RO.

TransDAT RO, a 32-bit Windows app, was long a reference tool for coordinate transformation. However, it has some limitations:

TransDAT RO Limitations	ROMGEO Advantages
Windows-only (EXE)	Web access, multiplatform
Rigid input/output formats	Flexible data parser
File-only input; no textbox	Textbox + export to CSV, DXF, SHP
No support for large datasets	Fast transformations on large batches
CPU-only	Optional GPU acceleration
Outdated interface	Modern and intuitive web interface

ROMGEO uses modern geospatial libraries and reproduces the exact same geodetic transformations as TransDAT RO, including the same official grid models (.spg). Results are identical between the two for any given input.

This demo page is designed for:

• Field survey operators
• GIS and geodesy specialists
• Engineers needing fast transformations in Romania

It allows instant conversion of ETRS89 geographic coordinates into EPSG:3844 projected coordinates, with no software installation or preprocessing required.

The ROMGEO Demo Page is divided into intuitive sections:

🔹 Input Panel

• Text field to paste or input coordinates line by line
• Supports up to 50,000 characters of raw data
• Click Transform to process
• Invalid or out-of-grid lines are marked as Input error or Out of bounds

🔹 Results Table

Displays transformed coordinates per valid point, in the order:

• X (North) – STEREO70 coordinate
• Y (East) – STEREO70 coordinate
• Hmn – Normal height (Black Sea 1975)

Displayed columns include:

Column	Description
Point Name	Label, if specified
Latitude	Interpreted latitude (ETRS89)
Longitude	Interpreted longitude (ETRS89)
Altitude	Ellipsoidal altitude
X	North (EPSG:3844 – STEREO70)
Y	East (EPSG:3844 – STEREO70)
Hmn	Normal height (Black Sea 1975)
Status	OK / Input Error / Out of Bounds
	📌 Center map on point

🔹 Export Options

• Buttons to download results:
• CSV – Excel/database compatible
• DXF – 3D points for AutoCAD
• SHP – ESRI Shapefile for GIS apps
• Error lines are excluded from export files

🔹 Interactive Map

• Dynamic map of transformed points
• Includes:
• Zoom In / Zoom Out
• “Center all points” button
• Measurement tool
• Location button

One of ROMGEO’s key strengths is its flexible input parser. You can paste coordinates in a wide range of human-readable formats, as long as the following structure is respected:

✅ Per Line Format:

[PointName]  [Separator]  Latitude  [Separator]  Longitude  [Separator]  Altitude

• PointName: optional (alphanumeric)
• Separators: space, tab, comma, semicolon, vertical bar "|" – can be mixed
• Latitude: must be between ~43.5° and 48.5°
• Longitude: between 20° and 30°
• Altitude: required; positive or negative in meters

💡 Accepted Examples:

P01 45.123456 25.123456 120.5
45.123456,25.123456,112
Alpha|46.345;26.999;134.2
45 12 34 N 25 12 34 E 100
45°12′34″N, 25°12′34″E, 100
45 12.3456 N; 25 34.5678 E; 105

• Supports decimal degrees and DMS (degrees, minutes, seconds)
• Minute/second overflow handled automatically (e.g., 100 minutes = 1 degree 40 minutes)

Results are returned in the following order and format:

Field	Description
X	North (EPSG:3844 – STEREO70)
Y	East (EPSG:3844 – STEREO70)
Hmn	Normal height (Black Sea 1975)

• Coordinates are converted from EPSG:4258 → EPSG:3844
• Easy to copy or export in CSV, DXF, SHP

ROMGEO is optimized for speed and scalability:

• Backend engine: FastAPI + Numba
• Bicubic interpolation on 3D grids (.spg)
• Real-time batch processing:
• ~1 million points/sec on typical CPU
• 4–6 million points/sec on high-end CPU
• Over 15 million points/sec with GPU (server)

• 🔢 Input limit: max 50,000 characters in textbox (browser compatibility)
• 📂 No file uploads: paste-only in demo; for large datasets, use the API directly
• 🕒 Potential delays: may take a few seconds depending on data size and server load
• 🔁 Inverse transforms (e.g., STEREO70 → ETRS89) will be added in a future update
• 🧮 Large minute/second values: automatically normalized (100 minutes = 1° 40’)
• 🗺️ 📌 in table: centers the map on the respective point
• ⚠️ Input/Out of Bounds errors: auto-marked per line
• 🧹 Export filtering: error lines are excluded from CSV, DXF, SHP

ROMGEO is a modern, accurate, and fast alternative to classic geodetic coordinate transformation apps. It’s field-ready, browser-based, with no installs or complex setup.

• Uses the same official grid models as TransDAT RO
• Accepts flexible input formats
• Enables quick result export
• Compatible with modern GIS and CAD workflows

Visit: https://api.romgeo.ro/api/v1/demo.html

Paste your coordinates, click Transform, and download the results.

📌 Same geodetic science, with a modern interface.