Crafter.Graphics/examples
catbot 574242dd30 perf(ui): add additive DispatchFused to collapse consecutive UI passes (#47)
Add a fifth UI compute path — DispatchFused — alongside the four
per-element Dispatch* calls. It composites quads → circles → images →
text (canonical back-to-front order) in ONE dispatch that loads the
destination image once and stores once, eliminating the per-pass
load+store and the inter-pass VkMemoryBarriers a run of consecutive
Dispatch* calls would pay. The win materialises at >= 2 non-empty
categories; an absent category is a zero-trip, push-constant-uniform
loop (~free).

The new uber-kernel (shaders/ui-fused.comp.glsl) reuses each category's
exact cooperative shared-memory tile-cull + per-pixel accumulate, so a
fused category is pixel-identical to its standalone pass. Categories run
sequentially per thread and share one set of shared-memory scratch, so
the VGPR/shared high-water mark stays at the per-category level, not the
sum.

Additive and non-breaking: the per-element Dispatch* calls and the
frozen 48-byte UIDispatchHeader are untouched. DispatchFused gets its own
128-byte push-constant layout (UIFusedHeader: four uvec4 headers + four
per-category clip vec4s). To interleave a custom ui.Dispatch() between
standard passes, bracket it with two DispatchFused calls — the dispatch
boundary is the explicit, app-declared flush point.

WebGPU (Vulkan-second): DispatchFused falls back to the per-element
Dispatch* calls in canonical order — one texture/sampler per dispatch
there can't feed the bindless image phase — so the result matches; only
the load/store fusion is Vulkan-only.

HelloUI now composites its background quads, mouse circle, and label
text in a single DispatchFused. Verified rendering identical on a live
Vulkan/Wayland session.

Resolves #47

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
2026-06-16 17:03:24 +00:00
..
CustomShader custom shader webgpu 2026-05-18 05:39:17 +02:00
Decompression compression example 2026-05-12 00:27:55 +02:00
HDRBloom test(webgpu): HDRBloom example exercising the HDR post-process primitives (#27) 2026-06-09 12:55:14 +00:00
HelloDom webgpu support 2026-05-18 04:58:52 +02:00
HelloUI perf(ui): add additive DispatchFused to collapse consecutive UI passes (#47) 2026-06-16 17:03:24 +00:00
HelloWindow crafter-build V2 2026-04-30 01:29:17 +02:00
InputSystem new input system 2026-05-12 00:24:48 +02:00
RayQueryPick feat(webgpu): HDR post-process primitives — float textures, storage-texture bindings, RESOLVE→HDR target (#27) 2026-06-09 12:55:14 +00:00
RTMultiShadow test(webgpu-rt): RTMultiShadow example exercising N shadow rays/pixel/bounce (#30) 2026-06-09 22:45:33 +00:00
RTStress feat(webgpu): HDR post-process primitives — float textures, storage-texture bindings, RESOLVE→HDR target (#27) 2026-06-09 12:55:14 +00:00
RTVolume example(RTVolume): GPU-written device-buffer procedural AABBs (#37) 2026-06-16 14:12:12 +00:00
Sponza feat(webgpu): HDR post-process primitives — float textures, storage-texture bindings, RESOLVE→HDR target (#27) 2026-06-09 12:55:14 +00:00
VulkanTriangle fix(vulkan-rt): merge TLAS push constant into existing block (#18) 2026-06-03 02:28:02 +00:00
README.md test(webgpu-rt): RTMultiShadow example exercising N shadow rays/pixel/bounce (#30) 2026-06-09 22:45:33 +00:00

Examples

Each example is a self-contained crafter-build project that depends on the parent Crafter.Graphics via LocalProject. To build and run any of them:

cd examples/<name>
crafter-build -r

Index

HelloWindow

Minimum viable program: open a window, run the event loop. No Vulkan rendering. Useful as a smoke test for Device::Initialize + Window + the platform backend.

VulkanTriangle

Ray-traced single triangle through vkCmdTraceRaysKHR. Shows the full ray-tracing setup: DescriptorHeapVulkan with image and buffer slots, PipelineRTVulkan from raygen / miss / closesthit SPIR-V, BLAS via Mesh::Build, TLAS via RenderingElement3D::BuildTLAS, direct vkWriteResourceDescriptorsEXT for swapchain views, RTPass on window.passes. Smallest test of the bindless ray-tracing path.

HelloUI

Compute-shader UI demo using all three UI tiers:

  • Tier 3 components: DrawButton, DrawSlider, DrawProgressBar, composed via Rect::SubRect for resize-safe layout.
  • Tier 2 standard shaders: DispatchQuads for the background and components, DispatchCircles for a cursor-tracking dot, DispatchText for the button label (with the FontAtlas wired up to UIRenderer).
  • Tier 1 is available too — any custom ComputeShader registered on the same heap can be dispatched alongside the standard ones.

Hit-testing and animation are user code (see the EventListener subscriptions on window.onMouseMove / onMouseLeftClick); the library does not track widgets or focus.

Drop a TTF in this directory as font.ttf before running (the example loads it via Font("font.ttf")).

InputSystem

Guided tour of Crafter::Input: name actions ("Jump", "Move", "Fire", "Look", "Zoom"), bind them to keys / mouse / gamepad (with composite bindings for WASD-as-Vector2 and analog sticks), and consume them as events. Demonstrates:

  • The compile-time Key(CrafterKeys::Space) helper that folds to a per-platform raw scancode — bindings stay cross-platform-readable in source while runtime data stores raw codes only.
  • All four action types (Button, Axis1D, Vector2) with multiple bindings per action (any-of semantics).
  • Map::StartRebind — press R, then press any input to remap "Jump" at runtime. Captured input is filtered out for that frame.
  • BindingToString / BindingFromString round-trip — print the default bindings as the on-disk format.
  • Gamepad hot-plug events: plug a controller in mid-run and the bindings start firing immediately.

Console-driven (no UI rendering needed); focus the window and watch stdout.

CustomShader

Tier 1 demo: a user-authored compute shader (inverse-circle.comp.glsl) running alongside the shipped drawQuads. The custom shader inverts RGB under each item-circle — exactly the kind of effect attempt #2's closed shader couldn't express. Shows:

  • Defining your own item POD struct in C++ + matching std430 struct in GLSL.
  • #include "../../shaders/ui-shared.glsl" for the bindless heap declarations + UIDispatchHeader push-constant contract.
  • ComputeShader::Load for the .spv, UIRenderer::RegisterBuffer for your SSBO, FillHeader to populate the standard prefix, and UIRenderer::Dispatch to launch — the same pattern the standard shaders use under the hood.
  • The inter-dispatch SHADER_WRITE → SHADER_READ|WRITE barrier is inserted automatically, so the custom shader sees the colored stripes drawn by the prior DispatchQuads and reads/writes the swapchain image safely.

RayQueryPick

Regression test for the WebGPU software ray-query shim. Builds a 512-instance TLAS and shoots one ray through a rayQuery=true PlainComputeShader, reading the committed hit back to the host and checking it against the analytically-known answer. Guards against the hardcoded-leaf-start TLAS-traversal bug (issue #25) that made every rayQuery pick miss for realistic instance counts. WebGPU/DOM only.

HDRBloom

Cross-backend-shaped HDR bloom on the WebGPU backend (issue #27). The RT pipeline's RESOLVE writes linear radiance into a user rgba16float texture (StorageImage2D, PipelineRTWebGPU::Init(..., RGBA16Float)), two PlainComputeShader passes threshold + blur it through float storage targets (UICustomBindingKind::StorageTexture), and a UI custom shader composites scene + bloom with a Reinhard tonemap onto the canvas. Exercises the three primitives an HDR post-process chain needs: float textures, write-only storage-texture bindings, and pre-tonemap radiance out of the wavefront. The threshold/blur passes run from onBeforeUpdate so each gets its own queue submit — the storage-write → sampled-read barrier WebGPU only provides between submits (or between passes), never within a single compute pass. WebGPU/DOM only; the same chain is wireable on Vulkan today via an offscreen HDR heap image + a composite RenderPass (the present path records passes generically and barriers between them).

RTMultiShadow

Multi-light shadowing through the wavefront RT pipeline (issue #30). Five pillars on a checkered ground, four colored point lights; the closest-hit emits one shadow ray per light from the same invocation, so up to four rays per pixel resolve in a single SHADE pass. Exercises both halves of the >1-ray-per-pixel-per-bounce widening: the atomic rtAccumulate (per-channel f32 CAS — concurrent same-pixel adds don't race) and RTPass::raysPerPixel (scales the ray/hit/payload buffers so the per-light emits aren't capacity-dropped). Any regression shows up as flickering dark noise or a missing shadow color in the overlap regions. WebGPU/DOM only.