01 Foundation - Rasterization Base¶

01 Foundation - rasterization base result

This tutorial demonstrates a modern Vulkan 1.4 raster-based renderer that serves as the foundation for all subsequent ray tracing tutorials. It showcases a complete glTF scene renderer using Shader Objects, Push Descriptors, and Dynamic Rendering - the same modern Vulkan features that make ray tracing conversion straightforward and efficient.

Key Features¶

Modern Vulkan Pipeline: Shader Objects and Push Descriptors for flexible rendering
glTF Scene Loading: Complete glTF 2.0 support with tinyGLTF integration
GPU Resource Management: Efficient mesh and texture handling with nvsamples::GltfMeshResource
Dynamic Rendering: Modern Vulkan 1.4 features for simplified pipeline management
Post-Processing: Tonemapping and sky rendering capabilities
Ray Tracing Ready: Architecture designed for minimal changes when converting to ray tracing

Architecture Overview¶

This implementation uses a traditional graphics pipeline with vertex and fragment shaders, but leverages modern Vulkan 1.4 features that simplify the transition to ray tracing. The pipeline processes glTF scenes through vertex transformation, material shading, and post-processing stages.

Pipeline Type: Traditional graphics pipeline with vertex/fragment shaders
Modern Vulkan Features: Shader Objects, Push Descriptors, Dynamic Rendering
Scene Management: glTF loading and GPU resource management
Rendering Method: vkCmdDrawIndexed with modern descriptor binding

Key Components¶

Scene Loading: tinyGLTF integration with complete glTF 2.0 support
Resource Management: nvsamples::GltfMeshResource and shaderio::GltfSceneInfo
Modern Pipeline: Shader Objects and Push Descriptors for flexible binding
Shader Language: Slang shaders for modern cross-platform compatibility
Post-Processing: Tonemapping and sky rendering with dedicated shaders

Shader Structure¶

Vertex Shader¶

[shader("vertex")]
VSout vertexMain(VSin input, uint vertexIndex: SV_VertexID)
{
  // Transform vertex position and normal to world space
  float4 pos = mul(float4(posMesh, 1.0), instance.transform);
  output.sv_position = mul(pos, sceneInfo.viewProjMatrix);
  output.worldPos = pos.xyz;
  return output;
}

Fragment Shader¶

[shader("pixel")]
PSout fragmentMain(VSout stage)
{
  // PBR material shading with light calculation
  float3 color = pbrMetallicRoughness(albedo, metallic, roughness, N, V, L);
  color *= light.color * light.intensity;
  return float4(clamp(color, 0.0, 1.0), 1.0);
}

Key Differences from Ray Tracing¶

Pipeline Type: Graphics pipeline → Ray tracing pipeline
Shader Types: Vertex/Fragment → Ray generation/Closest hit/Miss
Geometry: Vertex buffers → Acceleration structures
Rendering: vkCmdDrawIndexed → vkCmdTraceRaysKHR
Descriptors: Added TLAS and output image bindings
Memory: Added SBT buffer for shader binding table

Implementation Highlights¶

This foundation enables: - Modern Vulkan Features: Shader Objects and Push Descriptors simplify ray tracing conversion - Efficient Resource Management: glTF loading and GPU resource handling remain unchanged - Flexible Shader System: Slang shaders provide cross-platform compatibility - Post-Processing Pipeline: Tonemapping and sky rendering work with both raster and ray tracing

Usage¶

Controls¶

Mouse: Rotate camera around the scene
WASD / Arrow Keys: Move camera
Q / E: Move camera up/down
Right Mouse + Drag: Pan camera
Scroll Wheel: Zoom in/out
UI Panel: Adjust tonemapper, sky, and material parameters

Scene Format¶

Supports glTF 2.0 scenes (embedded or binary)
Place textures and models in the working directory or provide a path

Next Steps¶

For conversion to ray tracing, see 02_basic which demonstrates the step-by-step transformation from this raster foundation to a complete ray tracing implementation.

This foundation can be extended with: - 02_basic - Convert to ray tracing with BLAS/TLAS and ray generation - 03_any_hit - Add transparency and alpha testing - 04_jitter_camera - Implement temporal anti-aliasing - 05_shadow_miss - Add efficient shadow rays - 06_reflection - Introduce reflection and global illumination

For detailed conversion information: - Ray Tracing Tutorial - Step-by-step conversion guide - Acceleration Structures Guide - BLAS/TLAS construction and management - Shader Binding Table Guide - SBT creation and alignment