Ground Truth Generation
=======================

ACSim provides ground truth generation functions for **mask**, **3D depth**, and **optical flow**.

Overview
--------

To activate ground truth saving, use the built-in version of ACSim and enable one or more of the following options:

- **mask**
- **depth**
- **ele** (elevation angle)

By default:
- **mask** and **ele** are saved as `.png` files
- **depth** is saved as a `.npy` file

> ⚠️ When setting the output path, please make sure the file extension matches the expected format (e.g., `.png` for mask, `.npy` for depth).

.. image:: _static/gt.PNG
   :alt: Ground truth sample
   :align: center

For **optical flow**, since it requires two different poses, it is recommended to use a Python script to generate the output as follows.

Flow
----

To generate optical flow ground truth, ACSim provides a dedicated setup.

1. Open the ``of.blend`` file located in the built-in folder.
2. Go to the **Scripting** workspace in Blender.
3. Run the provided flow script to generate and save the flow data.