Setting Up a PBR Scene
The PBR material system in NGE uses Image-Based Lighting (IBL) to enable advanced features like environment reflections, refractions, global illumination, and more.
This allows for highly realistic rendering of materials under various lighting conditions. However, it requires additional setup in the scene. Specifically, a LightProbe must be configured to provide the necessary lighting information.
The LightProbe can be pre-baked or dynamically generated based on the scene’s environment.
In this guide, we'll cover the basic and most straightforward way to set up a PBR scene using a Sky or other supporting environment geometry, along with the NGE Accelerated Baker to generate the required LightProbe in near real-time.
Step-by-Step Setup¶
Attach a Sky (or Supporting Geometry) to the rootNode¶
This geometry provides the visual environment used during the LightProbe bake.
Spatial sky = SkyFactory.createSky(assetManager, skyTexture, SkyFactory.EnvMapType.EquirectMap);
rootNode.attachChild(sky);
Add EnvironmentProbeControl to the Scene¶
This control manages the generation and assignment of the LightProbe for the node it's attached to and all its children.
int resolution = 256; // Resolution of the environment probe
rootNode.addControl(new EnvironmentProbeControl(assetManager, resolution));
Tag the Supporting Scene Geometry¶
To ensure the environment is used during LightProbe baking, tag it using EnvironmentProbeControl.tagGlobal():
EnvironmentProbeControl.tagGlobal(sky);
That’s It!¶
On the first frame, the EnvironmentProbeControl will bake the LightProbe and apply it automatically to all PBR materials in the scene.
No further setup is required: materials will pick up the probe lighting automatically.
Advanced Usage¶
You can use multiple EnvironmentProbeControl instances within a scene. Their generated LightProbes will blend together using their position and radius as weights.
To assign specific environment geometries to individual probes, use the instance method tag(spatial) instead of the global one:
environmentProbeControl.tag(myCustomEnvironmentSpatial);
This gives you finer control over which parts of the scene contribute to each LightProbe.