Tom Sirdevan, look developer and lighting artist, explains what deferred shading is and how Unreal utilizes this approach to rendering to improve performance and more easily make available screen-space effects. He demonstrates this with screen-space reflections as well as screen-space ambient occlusion.
- [Voiceover] Unreal is primarily…a deferred rendering engine.…Before deferred shading, every material…in the scene had the job of calculating…how the material behaves…and interacts with light in a 3D context.…With deferred shading, things are done a little differently.…All of the components needed needed to calculate…a material are written to frame buffers.…A frame buffer is essentially an image,…a 2D array of pixels.…The components include the color,…specular, roughness,…normals,…depth data, and probably more.…And they're written to the frame buffer…and was called screen space,…which is to say…placed in their…final position for the camera.…
These frame buffers are then sampled…by each material to calculate the material's behavior…and interaction with light.…As a result of being able to quickly…sample these frame buffers,…rendering engineers began to realize…that they could also sample these frame buffers…to approximate dynamic lighting features…like reflections and occlusion,…and do so much more quickly than in 3D space.…
Author
Tom Sirdevan
Released
7/6/2016- Direct lighting
- Indirect lighting
- Creating a sky with Blueprint
- Deferred shading
- Dynamic sky and sun
Share this video
Embed this video
Video: Deferred shading effects