Window
- CreateSwapchain asked for exactly numFrames (3) images whatever the
surface said, read them into a three-element array, and keyed the
command buffers, the fences and the descriptor-heap copy holding "its"
swapchain image by the acquired image index. A swapchain of another
size fell back to FIFO (asked for MAILBOX or IMMEDIATE) or threw, and a
surface whose minimum is above three got a create info below it
(#160). Mesa's MAILBOX needs four images: Turnip on phoc, llvmpipe on
any Wayland compositor.
- The present mode is picked first, then the swapchain is sized by
SwapchainCapabilities: the surface's counts for that mode where the
instance has surface_maintenance1. With swapchain_maintenance1 the
swapchain names its mode (VkSwapchainPresentModesCreateInfoKHR), which
is what makes the mode's own count the one that applies, at creation and
to the forward progress of a UINT64_MAX acquire; without it the stricter
of the mode's and the surface's counts for all modes. It asks for
numFrames or that minimum where more, never past the maximum
(SwapchainMinImageCount). Turnip's FIFO keeps its three images and
MAILBOX gets four. The FIFO fallback and presentModeUnfit are gone.
- images, imageViewInfos (was imageViews: they are create-infos), the made
imageViews that descriptor sets take, imageInitialised and the
render-finished semaphores are per image, as many as the driver made.
The views are made once per swapchain. The semaphores only grow, since
a present of the old swapchain may still wait on one.
- Frames in flight stay numFrames, keyed by currentFrame, frameCounter %
numFrames: the command buffer, the fence, the acquire semaphore, the
heap copy (or set), RenderingElement3D::tlases, the frameIdx a pass is
recorded with. currentImage is the acquired image. currentBuffer is
gone, so code that used it stops compiling instead of picking the wrong
one; RenderPass::Record's frameIdx keeps its name and is now the frame
slot, as RenderPass.cppm says.
- The frame's fence is waited before the acquire. The acquire semaphores
need no spare then, and a frame waits for exactly the one numFrames
before it, which the deletion queue and the staging rings count on and
fences keyed by image did not promise once images come back out of
order. The swapchain slots are written before the fence is reset.
- From the acquire to the present the window is recording: a Resize or
SetPresentMode from a listener (a VSync key ticked in onUpdate) takes
effect after the present, through RebuildSwapchain, together with a
present that found the swapchain out of date. Rebuilding mid-frame used
to destroy the image the frame was drawing into; with images sized per
swapchain it would also index past the new one's end.
DescriptorHeapVulkan
- Frames and images pair up differently from frame to frame, so no heap
copy can keep one swapchain image. AddSwapchainSlot(slot, window) lists
an image slot as that window's swapchain image, and Window::Render
writes the image a frame acquired into its window's listed slots in that
frame's copy, or its set, before onUpdate, skipping a slot that holds it
already. A slot is one window's, so two windows can share a heap without
writing each other's slots under each other's frames in flight. A slot
listed during a frame its window records is written at once. A slot past
the heap's image slots, an empty ImageSlot's 0xFFFF among them, is
refused. Freeing a slot unlists it, as does initialising the heap in
either binding model. WriteImageSet, the one use of which this
replaces, is gone, and with it the per-frame dimension of setImageViews.
Device
- VK_KHR_surface_maintenance1 (or EXT) and VK_KHR_get_surface_capabilities2
are enabled where the loader has them (surfaceMaintenance1Supported,
vkGetPhysicalDeviceSurfaceCapabilities2KHR), and the matching
swapchain_maintenance1 with its feature where the device has it
(swapchainMaintenance1Supported).
- DistinctGpus groups the physical devices by GPU as CRAFTER_GRAPHICS_DEVICE
numbers them, for ChooseGpu and tests.
UI
- UIRenderer lists its output slot instead of writing every copy itself,
and again on every resize; the resize listener is gone on both
backends. The headers' frameIdx is currentFrame.
Examples
- VulkanTriangle, Sponza, SponzaBench and RTVolume list their output slot
and write only the per-frame TLASes. They wrote imageViews[f] into copy
f once, which a resize left pointing at destroyed images.
Tests
- SwapchainImageCount: SwapchainMinImageCount on the numbers drivers
report; every offered mode keeps its mode and gets what the window asks
for; every frame presents the colour it drew, read back a texel per
frame; a switch and a resize asked for during a frame wait for its
present; a slot listed during a frame holds its image at once; two
windows on one heap draw their own colours. The frame checks run again
in child processes, through CRAFTER_GRAPHICS_DEVICE, on a GPU whose
swapchains have more images than frames (this one, else llvmpipe), in
each binding model the parent didn't cover; a child skips only for a GPU
that can't run the library, and checks it runs the model it was asked
for.
- FrameLoopSync checks the frame slot follows the frame counter and counts
the swapchain's own images. HeapASRead, HeapDynamicIndexHit and
RTPassPushData list their swapchain slot and drop their resize rewrites.
Docs
- README, AGENTS.md and AGENTS.consumer.md: frames and images, the
swapchain slots, rebuilds held to the present, the new optional groups.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
DescriptorHeapVulkan
- The buffer region started at images * imageDescriptorSize /
bufferDescriptorSize, rounded down. A descriptor_heap array indexes
the heap from byte 0 in strides of its descriptor size, so buffer slot
0 has to sit on a whole buffer descriptor past the images. Where the
image descriptors were not a whole number of buffer descriptors, the
first buffer descriptors overwrote the last image descriptors. Where
they were less than one, the start was bumped to descriptor 1, but the
heap was still sized as if the buffers began right after the images,
so the last buffer descriptors went into the implementation's reserved
range. Every descriptor size is a power of two, so both cases need
image descriptors smaller than buffer descriptors, which NVIDIA (32
and 16 bytes) and llvmpipe (64 and 16) do not have. The start now
rounds up and the heap is sized from it (#163).
- The reserved range sat at a multiple of imageDescriptorAlignment only,
where vkCmdBindResourceHeapEXT also wants bufferDescriptorAlignment
(VUID-vkCmdBindResourceHeapEXT-pBindInfo-11435 and -11436). It now
starts on a multiple of the larger. The buffer descriptors need no more
than the rounding: each alignment is at most its descriptor size, so a
whole number of descriptors is aligned.
- bufferStartElement is 16 bits and took the division unchecked, so an
image region past 65535 buffer descriptors (16384 images on llvmpipe)
wrapped the buffer region around onto the images. Slot counts whose
buffer indices do not fit 16 bits, 0xFFFF being the empty slot, now
throw, naming the counts. A heap without buffer slots has no buffer
region, which starts at 0 as in descriptor-set mode, so image-only
heaps have no index to fit.
- On a driver that reserves nothing (llvmpipe), a heap without sampler
slots was a zero-size buffer, which every Initialize(1, 1, 0) made,
and Window::Render bound its address each frame. Each heap now holds at
least one descriptor, as each binding does in descriptor-set mode. That
grows NVIDIA's sampler heap by one descriptor when no sampler slots are
asked for; the resource heaps of the slot counts in the tree keep their
layouts byte for byte.
- ComputeLayout holds the arithmetic, pure over the descriptor-heap
properties, and Initialize goes through it. GetBufferOffset and
GetBufferOffsetElement, which had their own copies of the old
arithmetic and never had a caller, are gone.
- Bind(cmd, frame) binds a frame's heaps with the reserved ranges
Initialize stored, or in descriptor-set mode the frame's descriptor
set. Window::Render and the RTVolume example worked the reserved-range
offset out from the heap's size with the image-alignment mask, and
call Bind now. The window's per-heap cache of bind structs goes with
it: keyed on the heap pointer, it kept binding the old buffers after a
re-Initialize that reallocated them. The heap still ends with its
reserved range, so code that derives the offset from the size keeps
getting the right one.
Tests
- DescriptorHeapLayout: the issue's two layouts, the reserved range where
buffer descriptors are aligned more strictly than image ones, every
legal combination of descriptor sizes and alignments up to 256 bytes,
no heap empty, the NVIDIA and llvmpipe layouts, the 16-bit limit and
image-only heaps. Pure CPU, no device. Against the old arithmetic it
fails 12 of its 18 checks.
Docs
- README.md's heap bullet and AGENTS.consumer.md say how to bind the
heap outside the frame loop, and the consumer notes that Initialize
throws when buffer indices would pass 16 bits. AGENTS.md lists
ComputeLayout among the functions the pure-logic tests drive.
Closes#163.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
AGENTS.md
- Guidance for agents and contributors working on Crafter.Graphics: the
layout and the partitions by backend, the dev environment and the
targets, the build and test commands, how tests are declared and what
each group needs, code style, the design rules the code embodies,
commit conventions, security notes and gotchas. It carries the
dependency-notes section crafter-build 3.0.0 writes, holding
Crafter.Math's notes.
AGENTS.consumer.md
- What an agent working in a consumer needs: depending on the library,
the program shape and the frame order, device features, lifetimes, the
heap and its descriptor-set fallback, buffers and images, the UI tiers,
custom compute shaders, ray tracing, input, the DOM build, the
environment variables, testing a consumer, and which example to copy.
crafter-build injects it into consumers' AGENTS.md on their builds.
Both were reviewed against the code. The review found that --timing no
longer compiles (#178), which both files note.
Co-Authored-By: Claude Fable 5.1 <noreply@anthropic.com>
