Module pipeline

tessera_ui::renderer::compute

Module pipeline 

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GPU compute pipeline system for Tessera UI framework.

This module provides the infrastructure for GPU compute operations in Tessera, enabling advanced visual effects and post-processing operations that would be inefficient or impossible to achieve with traditional CPU-based approaches.

§Architecture Overview

The compute pipeline system is designed to work seamlessly with the rendering pipeline, using a ping-pong buffer approach for efficient multi-pass operations. Each compute pipeline processes a specific type of compute command and operates on texture data using GPU compute shaders.

§Key Components

§Design Philosophy

The compute pipeline system embraces WGPU’s compute shader capabilities to enable:

  • Advanced Post-Processing: Blur, contrast adjustment, color grading, and other image effects
  • Parallel Processing: Leverage GPU parallelism for computationally intensive operations
  • Real-Time Effects: Achieve complex visual effects at interactive frame rates
  • Memory Efficiency: Use GPU memory directly without CPU roundtrips

§Ping-Pong Rendering

The system uses a ping-pong approach where:

  1. Input Texture: Contains the result from previous rendering or compute pass
  2. Output Texture: Receives the processed result from the current compute operation
  3. Format Convention: All textures use wgpu::TextureFormat::Rgba8Unorm for compatibility

This approach enables efficient chaining of multiple compute operations without intermediate CPU involvement.

§Implementation Guide

§Creating a Custom Compute Pipeline

To create a custom compute pipeline:

  1. Define your compute command struct implementing ComputeCommand
  2. Create a pipeline struct implementing ComputablePipeline<YourCommand>
  3. Write a compute shader in WGSL
  4. Register the pipeline with ComputePipelineRegistry::register

§Performance Considerations

  • Workgroup Size: Choose workgroup sizes that align with GPU architecture (typically 8x8 or 16x16)
  • Memory Access: Optimize memory access patterns in shaders for better cache utilization
  • Resource Reuse: Use the ComputeResourceManager to reuse buffers across frames
  • Batch Operations: Combine multiple similar operations when possible

§Texture Format Requirements

Due to WGPU limitations, compute shaders require specific texture formats:

  • Input Textures: Can be any readable format, typically from render passes
  • Output Textures: Must use wgpu::TextureFormat::Rgba8Unorm for storage binding
  • sRGB Limitation: sRGB formats cannot be used as storage textures

The framework automatically handles format conversions when necessary.

Structs§

ComputeBatchItem
Strongly typed metadata describing a compute command within a batch.
ComputeContext
Provides comprehensive context for compute operations within a compute pass.
ComputePipelineRegistry
Registry for managing and dispatching compute pipelines.
ErasedComputeBatchItem
Type-erased metadata describing a compute command within a batch.

Traits§

ComputablePipeline
Core trait for implementing GPU compute pipelines.