dom-webgpu.js capped maxStorageBuffersPerShaderStage at 16 even when the
adapter reports far more (64 in our test env). The wavefront SHADE kernel
already binds ~16 storage buffers before any user binding, so any RT
pipeline declaring 2+ user storage buffers at @group(3) overflowed the
limit and failed to build with "Too many bindings of type StorageBuffers".
Request the adapter's reported maxStorageBuffersPerShaderStage /
maxStorageBuffersInPipelineLayout instead of a fixed 16. `clamp` already
mins against the adapter cap, so baseline-only devices still get a valid
request, and the `|| 16` fallback + the `typeof cap === "number"` guard
handle limit names a browser doesn't expose (Firefox returns null for
maxStorageBuffersInPipelineLayout).
Verified in-browser: a 17-storage-buffer compute pipeline fails with the
exact reported error on a device clamped to 16, and builds cleanly on a
device requesting the adapter's 64. RTStress renders correctly.
Resolves#8
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
Two Vulkan validation errors fired on startup of every native (Vulkan)
example, reported in #5:
1. vkCreateDevice enabledLayerCount != 0. Device layers are deprecated
and ignored since Vulkan 1.0; passing them is a spec violation
(VUID-VkDeviceCreateInfo-enabledLayerCount-12384). The device-layer
enumeration/match block in Device::Initialize is removed and
enabledLayerCount is pinned to 0 — layers are enabled at the instance
only.
2. vkQueueSubmit layout transition on a presentable image that "has not
been acquired". StartInit() and RecreateSwapchainAndImages() eagerly
transitioned every swapchain image UNDEFINED -> PRESENT_SRC_KHR before
any vkAcquireNextImageKHR, which the spec forbids (a presentable image
may only be touched after acquire). Those pre-transitions are removed.
Each image's first layout transition now happens lazily in Render(),
after acquire, from UNDEFINED; subsequent frames transition from
PRESENT_SRC_KHR. A per-image `imageInitialised` flag (reset in
CreateSwapchain) selects the correct oldLayout.
Verified under sway (headless, GPU renderer) + VK_LAYER_KHRONOS_validation:
the original code reproduces both errors on HelloUI; the fixed build emits
zero validation messages across initial render and swapchain recreation.
Resolves#5
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
The LBVH bitonic sort still runs over the full 16384 (sentinels sink to
the tail), but the sweep tree is now built and traced at depth
log2(next_pow2(nReal)) instead of a fixed 14. Add nPadded to LbvhPC; leaf
init + bottom-up refit use it; the host passes the same next_pow2 to the
trace via WfParams.tlasNPadded. Renders correctly at 512 instances
(depth 9). The fragile sort phases are untouched.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
The RT pipeline now only builds the wavefront kernels, so the old
single-megakernel traversal/traceRay block (rtWgslMegakernelHelpers) and
the unused rtWgslPrelude alias are dead. Remove them. The rayQuery compute
path keeps rtWgslMegakernelBindings (its own _rq* traversal uses it).
RTStress still renders correctly with the trimmed prelude.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
Add _rtAabbT (AABB test returning entry-t); in both _rtwTraverseBlas and
_rtwTraverseTlas descend the nearer child first and push the farther only
when it hits, re-culling it against the (tightened) bestT when popped.
Render is identical (same closest hit) on VulkanTriangle, RTStress
(512/4096), and Sponza; cuts node visits on dense scenes.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
Restructure Sponza for the wavefront model: raygen emits the primary ray;
closesthit (in SHADE) gathers albedo/normal, accumulates ambient, and
emits a shadow ray carrying the pending direct term; miss adds the sky
(primary) or the direct term (shadow miss). resolve.wgsl applies the same
Reinhard+gamma the megakernel raygen did inline. User bindings moved to
group 3 (groups 0..2 reserved). RTPass maxDepth=2.
Renders the atrium correctly through the wavefront pipeline (textures,
two-sided shading, sun+ambient, shadows, tonemap).
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
Request the timestamp-query feature; write begin/end timestamps around
each wavefront pass via timestampWrites; resolve + read back (deferred to
after submit) and print a per-pass us breakdown ~1x/sec. RTStress @ 512
instances, 1920x995: TRACE dominates, total ~1.8-3.0ms/frame.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
Replace the megakernel @compute entry with five wavefront kernels sharing
one module, connected by GPU ray/hit/payload buffers and a GPU-driven
indirect bounce loop:
GENERATE -> (PREP -> TRACE -> SHADE) x maxDepth -> RESOLVE
- TRACE contains zero user code (pure _rtwTraverseTlas/Blas, opaque-only).
- PREP publishes dispatchWorkgroupsIndirect args from the live ray count;
the indirect-args buffer lives in its own bind group so it is never
bound read-write in the same dispatch that consumes it as INDIRECT.
- New emit/accumulate API: rtEmitPrimaryRay / rtEmitRay / rtAccumulate,
plus an optional user Resolve stage (tonemap hook; identity by default).
- Per-pass WfParams via a dynamic-offset uniform ring (curIsA/bounce vary
between passes within one submit).
- Payload-typed wfPayload binding emitted in the codegen region after the
user's struct Payload; payload travels with each ray (2*W*H slots).
- Request maxBufferSize / maxStorageBufferBindingSize / maxComputeWorkgroups
PerDimension so the W*H-sized work buffers fit past the 128MB baseline.
VulkanTriangle ported to the new API and renders bit-identical to the
megakernel baseline at maxDepth=1.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
Replace the disabled LSD radix sort in lbvhBuildMain with a data-oblivious
workgroup bitonic sorting network and enable it. The radix scatter was gated
behind `if (false)` because it produced count/distribution-dependent
corruption (TODO-lbvh-sort.md) — a memory-ordering bug in the Hillis-Steele
scan / parallel scatter that surfaced only for certain Morton distributions
(a small object beside a tight cluster), making geometry flicker.
A bitonic network's compare-exchange schedule depends only on N_PADDED, never
on key values, so it sidesteps that entire class of distribution-dependent
races (TODO strategy #5). 105 sub-stages over 2^14 keys, single workgroup of
1024 threads, 8 compare-exchanges/thread/sub-stage, operating in-place on
sortA with a storageBarrier between sub-stages. Sentinel keys (0xFFFFFFFF)
compare largest and settle at the tail, exactly where Phase 4 expects them.
Restores Morton (Z-order) spatial coherence to TLAS BVH leaves, which the
many-instance case needs. Removes the now-dead radix histogram/scan workgroup
memory and constants.
Verified on the Firefox/Dawn WebGPU stack: a GPU unit test diffs the kernel
output against a CPU oracle across all three required distributions
(all-uniform, all-one-bucket, small-object-next-to-cluster) plus random,
reverse, and empty inputs — all match bit-for-bit with a valid index
permutation. Sponza renders correctly with the sort live.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
Both were on disk but missing from the V2 port's implementations list;
Rendertarget is required for RendertargetVulkan linkage, Shm is the
Wayland shared-memory helper.
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
