---
title: "Opposite Driving Side Converter"
slug: "opposite-driving-side-converter"
updated: 2026-08-20T14:53:46Z
published: 2026-08-20T14:53:46Z
canonical: "docs.safetypooldb.ai/opposite-driving-side-converter"
---

> ## Documentation Index
> Fetch the complete documentation index at: https://docs.safetypooldb.ai/llms.txt
> Use this file to discover all available pages before exploring further.

# Opposite Driving Side Converter

## **Overview**

The **Convert Driving Side** option transforms paired ASAM OpenDRIVE (.xodr) and OpenSCENARIO (.xosc) files between **Right-Hand Traffic (RHT)** and **Left-Hand Traffic (LHT)**.

By performing a full spatial mirror across road geometries, lane structures, vehicle spawn points, trajectories, and traffic rules, it ensures complete behavioral consistency without requiring manual scenario re-authoring. All converted datasets undergo automated ASAM schema re-validation and include synchronized OpenLABEL ground-truth metadata ready for immediate simulation.

---

## **Steps to Convert and Download Scenarios![Download Opposite Driving Side Converter](https://cdn.document360.io/d9bf0084-0d5b-468a-971b-537dce7153b6/Images/Documentation/Download_Left_right(1).png)**

1. Open any **OpenX Scenario** from your workspace.
2. In the top-right toolbar, click the **Download** dropdown button.
3. Select **Download Left-Hand Drive Scenario** (or **Download Right-Hand Drive Scenario**) from the available options.

**Note:** The downloaded `.zip` file contains 3 synchronized files: OpenDRIVE (.xodr), OpenSCENARIO (.xosc), and OpenLABEL (.json).

## **Handedness Transformation Mechanics & Conversion Logic**

When switching between Right-Hand Traffic (RHT) and Left-Hand Traffic (LHT), the platform applies a coordinate-level spatial reflection across a vertical mirror axis (x = 0 in world coordinates). The transformation guarantees geometric continuity, valid lane topology, and consistent vehicle maneuvers.

### **1. OpenDRIVE (Map & Infrastructure) Transformations**

- **Traffic Rule Definition:** Updates the road rule attribute to the target standard (RHT to LHT, or LHT to RHT).
- **Lane Groups & IDs:** Swaps left and right lane groups. All lane IDs are negated (for example, Lane +1 becomes Lane -1), ensuring driving directions align with the target traffic rules.
- **Plan-View Geometry:**
  - Reflects initial Cartesian positions: x' = -x
  - Adjusts heading angles: hdg' = π - hdg
  - Negates curve parameters (such as arc and spiral curvatures).
- **Superelevation & Crossfall:** Inverts lateral slope coefficients across the road profile (t-axis) from (a, b, c, d) to (-a, -b, -c, -d).
- **Objects & Road Signals:** Inverts lateral distances (t to -t) and orientations; remaps lane validity ranges (fromLane to toLane) to the mirrored lane IDs.
- **Junction Connections:** Updates all incoming and outgoing lane connection IDs to match the newly assigned lane IDs.

### **2. OpenSCENARIO (Vehicles, Positions & Actions) Transformations**

Vehicle behaviors, routes, and coordinate references are converted across all supported OpenSCENARIO positioning formats:

- **World Positions (WorldPosition):**
  - Horizontal position is reflected: x' = -x
  - Absolute yaw heading is transformed: hdg' = π - hdg
  - Roll angle is inverted: r' = -r (preserving vehicle bank in corners).
- **Lane Positions (LanePosition / RelativeLanePosition):**
  - Lane identifier is negated: laneId becomes -laneId
  - Lateral lane offset is negated: offset becomes -offset
  - Longitudinal distance along the road (s) remains unchanged.
- **Road Positions (RoadPosition / RelativeRoadPosition):**
  - Lateral offset t from the reference line is inverted: t becomes -t.
- **Relative Object Positions (RelativeObjectPosition):**
  - Entity-local lateral offset is inverted: dy becomes -dy while longitudinal distance (dx) and vertical distance (dz) remain intact.
- **Geographic Coordinates (GeoPosition):**
  - Longitude coordinates are reflected using tangent-plane projection relative to the map's geodetic reference origin (+lon_0, +lat_0).
- **Trajectories & Maneuvers:**
  - Clothoid/spiral curvature and curvature rate of change are inverted to mirror turning maneuvers accurately.
  - Linked road logic file paths are updated to point to the newly generated OpenDRIVE file.

### **3. Automated Validation & OpenLABEL Generation**

1. **ASAM Schema Compliance:** Both transformed XML files are validated against official **ASAM OpenDRIVE (v1.6.0)** and **ASAM OpenSCENARIO (v1.1.0)** XSD schemas prior to export.
2. **OpenLABEL Ground Truth:** An updated OpenLABEL JSON file is automatically compiled, containing full scene categorization, mirrored entity paths, and scenario tags.