Commit Graph

2 Commits

Author SHA1 Message Date
27577538cb re(xbg7): a capture names a never-decoding family, and the cause is mixed strides in one pool
capture_ib_truth now proposes an identity for each drawn buffer our decoder cannot
place, by matching (vertex, index) counts against declared-but-not-decoded
resources. That identified n201_01/_02/_03 in Stage_S02.xpr — three of the 63
resources that decode in no container — and the capture pins all four sub-meshes:

  #0 vb 0x32BA71C ib 0x32B39FC 4464 idx 777 v stride 24
  #1 vb 0x32BEFF4 ib 0x32B5CDC 4464 idx 869 v stride 24
  #2 vb 0x32C416C ib 0x32B7FBC  576 idx 192 v stride 24
  #3 vb 0x32C536C ib 0x32B843C 4464 idx 869 v stride 28   <- different

The layout matches our assumptions exactly (tight index packing, last buffer flush
against vb0 so pad 0, span 27936 == align4-summed markers, contiguous vertex
buffers, max index == verts-1 everywhere). The defect is that sub-mesh #3 has a
different stride AND its own vertex shader: anchor_grouped_meshes parses one
declaration per resource and applies its stride to every sub-mesh, so it reads #3
out of phase (372 non-finite position components of 2607), and since the pivot is
the largest index count with ties going to the last marker, the pivot IS that
sub-mesh — so the whole resource is declined.

Also adds examples/miss_targets.rs (which container to aim a capture at): 63
resources decode nowhere, 58 of them in exactly one container, clustering as
Stage_S16 21 (e901_wing_05_*), ptc_pack 12, Base 6, then per-stage n2xx groups.
Flying stage 16 did not draw the e901 wings — the container is resident but the
unit must also be on screen.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01NptfmpjdpNCKEez6d2xvA9
2026-08-13 10:52:35 +00:00
6d92e6c114 re(xbg7): the [index][vertex] layout is runtime-verified, and the indices= mystery was batching
The decoder's central unstated assumption — a block's index buffer sits
immediately before its vertex buffer (`vb - idx_count*2 - pad`, pad <= 3) — was
also the prime suspect for the residual anchor misses, since a capture-proven
`e106_eng_02_l` block was rejected outright. Measured it instead of assuming:

- extended the F10 ship capture to log each draw's index buffer (base, count,
  min/max index) and to key its de-dup on the index range, so every draw batch
  is recorded rather than only the first;
- `examples/capture_ib_truth.rs` places each drawn buffer in the container by its
  dumped positions and scores the capture against our decode.

Stage_S02, 42 drawn buffers placed: our idx_count == the sum of the draw's index
batches for 42/42, the batch union covers the vertex pool exactly for 42/42, and
all 30 single-block cases sit at pad <= 3 (20 at pad 0, 10 at pad 2). The other
12 are grouped pools, where one index pool serves the whole group. So the layout
holds, the decoded index count is exact, and eng_02_l died on the connectivity
gate (since replaced by the winding gate) — not on index location. The shipped
exact-coverage rule is independently confirmed.

The recorded "capture indices=21 vs our 246" disagreement was an artefact of the
old de-dup key: 21 was the first of two batches, 21 + 225 = 246. Any conclusion
from a pre-2026-08-13 capture's `indices=` or `vbase - ibase` is about one batch,
not about the block.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01NptfmpjdpNCKEez6d2xvA9
2026-08-13 05:57:44 +00:00