Commit Graph

4 Commits

Author SHA1 Message Date
Dion Moult 75b9963136 wgpu backend: --screenshot capability for visual verification
Pulls the capture half of task #10 forward so we stop flying blind from
stage 3 onward. WgpuViewportWindow gains captureNextFrameToPng(path);
the minimal driver wires it to a --screenshot PATH flag that renders
one frame, copies the surface texture back to host memory, writes a
PNG via QImage, and quits.

CopySrc is added to the surface configuration usage so the surface
texture can be the copy source. The texel-to-buffer copy honours
WebGPU's 256-byte bytes-per-row alignment by padding rows and stripping
the padding when assembling the QImage. Surface format 28 (BGRA8Unorm)
is byte-swapped to RGBA on the way into QImage::Format_RGBA8888;
RGBA8 surface formats are memcpy'd straight through.

Verified end-to-end on /tmp/basic.ifcview: 3 cube meshes/instances
render with depth, back-face cull, and the hemisphere-ambient + key+fill
lighting model — top face reads sky (bright), front faces read mid-tone,
exactly as the WGSL shading intended. The pixel-diff half of task #10
(comparing against a GL baseline) lands later when the GL minimal binary
gets an equivalent flag.

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>
2026-05-27 13:33:19 +10:00
Dion Moult bbf2bfde92 wgpu backend: vertex-pulling main render pass
Stage 3 of the wgpu port. Replaces the clear-only render loop with the
full main shading pass:

  - WGSL port of the GL main shader. Vertex-pulling: the vertex storage
    buffer is read as array<u32> in the shader, with pos/normal/color
    decoded manually per vertex. baseVertex (set per draw to mesh's
    vertex offset) folds into @builtin(vertex_index) automatically;
    firstInstance carries the instance slot for @builtin(instance_index).
    No vertex-input layout — vertex pulling means no IA bindings.

  - Render pipeline bound to depth-32-float (write-on, less compare),
    back-face cull, CCW front face. Pre-multiplies a [-1,1]→[0,1] z-remap
    matrix onto Qt's projection so WebGPU's clip-z convention is met.

  - Two bind groups: group=0 per-frame (uniform with view-proj + key/fill
    light + hemisphere ambient), group=1 per-model (three read-only
    storage buffers: vertices, mesh quant, instances).

  - Depth texture is created lazily and recreated on surface resize.

  - Orbit camera state on WgpuViewportWindow with viewAll() that frames
    the union of all loaded models' world AABBs after the first load.
    Mouse navigation lands later.

  - Draw loop: one drawIndexed per (mesh, instance) pair per model. This
    is correct but CPU-heavy on dense scenes; stage 6 introduces the cull
    + compacted visible list that lets multiple instances of one mesh
    collapse to a single call, and the eventual GPU-driven cull (post
    sunset of the GL backend) goes further.

Verified on /tmp/quad_v13.ifcview (1 mesh, 1 instance) and on a real v13
sidecar baked from basic.ifc via the GL minimal viewer (3 meshes,
3 instances, 864 B verts). No wgpu validation errors fire across pipeline
creation, depth attachment, bind groups, or the draw loop on either.
Visual confirmation deferred until --screenshot lands (task #10) which
is being pulled forward next so we don't keep flying blind.

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>
2026-05-27 13:19:09 +10:00
Dion Moult 9daa5fe195 wgpu backend: load .ifcview sidecars onto GPU buffers
Stage 2 of the wgpu port. WgpuViewportWindow gains a queueLoadSidecar
API (called from the minimal driver before init) and an applyCachedModel
that runs after init: reads via SidecarCache::readSidecar, allocates
four wgpu buffers per model (vertex storage, index, mesh-quant storage,
instance storage), uploads via wgpuQueueWriteBuffer, retains a CPU
mirror of the MeshInfo/InstanceCpu arrays for the cull and picking
paths that arrive in later stages.

MeshGpu (the per-mesh quantization basis) is derived from MeshInfo on
the fly; InstanceGpu (transform + ids) is derived from InstanceCpu and
uses the cached float transform — composing from placement_transformation
against federation-stage matrices lands when stage 5 wires those.

SidecarCache.cpp is compiled into IfcViewerWgpu directly: it's pure
C++ with no Qt/OCCT/IFC-parse deps, so dragging in the IfcViewer
static lib for one source file would be wasteful. This duplication
goes away once src/ifcviewer-core/ is extracted (task #12).

Verified on a synthesised v13 sidecar (4 verts, 6 indices, 1 mesh,
1 instance) and a multi-sidecar load that assigns successive model_ids.

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>
2026-05-27 12:48:03 +10:00
Dion Moult 19a39a0413 Scaffold experimental wgpu viewer backend
Adds src/ifcviewer-wgpu/ and src/ifcviewer-wgpu-minimal/ behind a new
BUILD_BONSAIVIEWER_WGPU option (default OFF), gated independently of
BUILD_BONSAIVIEWER. Stage 1 brings up a Qt window with a wgpu-native
v29 surface (X11) and clears to the background colour — no rendering
beyond that yet. Mirrors the lifecycle of the GL ViewportWindow so
subsequent stages (vertex-pulling renderer, pick, cull, HiZ, overlay)
slot in without restructuring the host.

wgpu-native is fetched as a pre-built binary release via FetchContent;
its .so SONAME is patched in at configure time so dependents get a
clean DT_NEEDED. The X11 native handle is obtained via the public
QNativeInterface::QX11Application API; Wayland and macOS/Windows
surface creation are stubbed with explicit "not wired yet" warnings.

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>
2026-05-27 12:23:23 +10:00