render-features.md 2.3 KB
Render features
A @'Stride.Rendering.RenderFeature' is responsible for drawing a given type of @'Stride.Rendering.RenderObject'.
Render phases
Render features have several phases.
Collect
The collect phase determines what needs to be processed and rendered. It's usually driven by the graphics compositor.
The collect phase:
- creates render views, and updating them with the most recent data such as view and projection matrices
- creates and setting up render stages
- performes visibility culling and sorting
Extract
The extract phase copies data from game states of previously collected objects to short-lived render-specific structures. It's usually driven by the @'Stride.Rendering.RenderSystem' and @'Stride.Rendering.RenderFeature's.
This should be as fast as possible and avoid heavy computations since game update and scripts are blocked. Heavy computations should be deferred to Prepare.
[!Note] Currently, Stride doesn't parallelize game updates and scripts, so they won't be resumed until the prepare and draw phases are finished.
Example tasks:
- copying object matrices
- copying material parameters
Prepare
The prepare phase prepares GPU resources and performs heavy computations. This is usually driven by the @'Stride.Rendering.RenderSystem' and @'Stride.Rendering.RenderFeature's.
Example tasks:
- computing lighting data and structures
- filling constant buffers and resource tables
Draw
The draw phase fills the GPU command list.
Example tasks:
- setting up render textures
- drawing combinations of render stage with render view.
Example
A typical example of views and stages created during collect phase, used during the draw phase:
Pipeline processors
Pipeline processors are classes called when creating the pipeline state. This lets you do things such as enable alpha blending or wireframe rendering in a specific render stage.
Stride includes several predefined pipeline processors. You can also create your own.