The publisher logo rendered its real artwork in isolation (3X) but was
overpainted in the full composite: every replayed draw used ONE fixed
SrcAlpha/OneMinusSrcAlpha pipeline + an opaque-magenta texture stub, so the
textured RectangleList draws whose sampler slot is shadowed by a vertex-fetch
constant (no resolvable texture) wrote opaque magenta over the logo.
Per-draw render-state inventory at the splash (env-gated probe, removed):
- logo QuadList vs=0x03b7b020 ps=0x03b79001: bc0=0x07010701
(One,OneMinusSrcAlpha — premultiplied alpha), cmask=0xF, ntex=1 (real K8888)
- RectangleList vs=0xd4c14f46 ps=0x03b79001: SAME premult blend, ntex=0
(slot 0 holds a type=3 vertex constant → texture decode rejects) → magenta
- opaque fill vs=0x36660986 ps=0xed732b5a: bc0=0x00010001 (One,Zero) — green
Draw order: the logo is drawn LAST per group, so order was not the problem;
the fixed pipeline state was.
Change (UI-side capture/replay only):
- draw_capture: capture RB_BLENDCONTROL0 + RB_COLOR_MASK (+ colorcontrol /
depthcontrol for follow-ups) per draw.
- xenos_pipeline: new RenderState{blend_control,color_mask}; map Xenos blend
factors/ops -> wgpu mirroring canary kBlendFactorMap/kBlendFactorAlphaMap;
One,Zero,Add => blend:None (opaque); zero-channel mask => ColorWrites; cache
translator AND interpreter pipelines keyed on (vs,ps,RenderState) /
RenderState so each draw composites with its real state.
- render: pass each capture's RenderState through both replay paths.
- dummy texture magenta(255,0,255,255) -> transparent(0,0,0,0): an
unresolvable texture now contributes nothing under its real premult blend
instead of fabricating opaque magenta (removes a fake, adds none).
Readback (env-gated, removed): full 1280x720 composite now shows the logo's
real artwork (maxR=255, 50-102 distinct colors/cell) in a centered strip; no
magenta anywhere. Background is uniform green (the 0xed732b5a opaque fill) — a
separate vertex-color/shader fidelity issue, NOT compositing (next iterate).
Determinism: UI-only; draw_capture additions only run when frame_captures=Some.
check -n50m --gpu-inline --stable-digest --expect = "matches golden" (2x).
cargo test --workspace = 682 passed. Temp probes removed.
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
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