An HDRI, which stands for High Dynamic Range Image, is a 360° image that is wrapped around our 3D scene for lighting and background purposes.

For example, it allows you replace the default sky with a sky texture that surrounds the scene.

Firstly, please open the HDRI tab in Actif3D Editor.

Imported the HDRI texture with the button at the HDRI texture.

The HDRI texture should be a 360 x 180° equirectangular panorama, otherwise it will have visible stitches. You can also directly use an HDR or EXR file downloaded from some internet source like https://polyhaven.com/hdris

The rotation of the sky texture relative to the scene.

These settings apply fog to the scene and control the fog parameters.

Enable exponential distance fog that will affect objects based on distance from the camera.

• Density - controls the density of the fog. The higher the value, the thicker the fog.
• Start - define how far from the camera the fog effect should start.

Enable exponential height fog, which affects objects based on their position on the Z-axis.

• Density - controls the density of the fog. The higher the value, the thicker the fog.
• Level - set the position on the Z-axis where the fog should start.

Specify the colour of the fog - this applies to both distance fog and altitude fog.