live_render.py connects to vpxlog.cpp's existing VPX_FIFOSOCK tee (the DOSBox-X
C012 device), consumes the game's wire AS IT ARRIVES, and runs the firmware and
the socket CONCURRENTLY -- pumping the socket whenever the firmware's receive
point drains -- rendering each draw with the shared verified GPU raster.
gpu_raster.py factors the M4c-raster renderer out of m4b_gpu so offline and live
share ONE render path (the 6-edge fp64 raster + verified texel decode).
feed_sock.py mimics vpxlog's FIFOSOCK server (streams a real capture in delayed
chunks) so the live path is validated end-to-end WITHOUT the flaky live pod.
Result: 12 frames streamed live at 2.3 fps; with --pin (equalized texture
availability) the live frames are BIT-IDENTICAL to the offline reference
(12/12 differ>24 = 0.000%) -- the seam is faithful. The default incremental
texture model is more authentic (the board only has texels it has received);
its divergence from offline is purely the M5-B tid%ntex placeholder, orthogonal.
Live topology now closed end-to-end offline:
game/capture -> C012 VPX_FIFOSOCK -> live_render -> firmware -> GPU -> frames.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
m4b_gpu.py moves the per-draw rasterization to a GPU compute shader (nearest-z
winner per pixel) with the verified M5 texel decode as a vectorized numpy
post-pass. Output matches the M5-verified CPU render (frame_*.png) bit-for-bit
across all 12 frames (differ>24 = 0.000%), at 1.4s/12 frames vs 69.9s (~50x;
the firmware's 3.7s now dominates -- the render keeps up with real-time).
Reaching bit-identity took finding two real bugs (honest trail in M4B-RESULTS.md):
1. 4-edge clip: the shader tested only edges[:4] while the CPU clips with ALL
edges (up to 6); 5-6-edge polys bled past their boundary and overwrote
neighbours -- the 18% region divergence on the receding walls/floor. Fixed
with 6 edge slots.
2. float32 planes: A*x+B*y+C in float32 flipped the z-test winner vs the CPU's
float64 at contested depths. Fixed with fp64 in the shader.
exp_precision.py is the diagnostic that REJECTED int-truncation as a reconciler
(it worsens float32/64 sensitivity to ~60%; true fixed-point width is a separate
spec item). Verified honestly by measuring, not eyeballing.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
m4b_frames.py fuses the two proven halves: battle_frames.py's live per-draw
program capture (from running-firmware C memory) + render_final.py's verified
M5 texel render (perspective divide + real-texture decode). Result: the whole
renderer chain runs offline from a real fifodump -- production VREND.MNG on the
C i860 core -> per-draw coefficient program -> faithful frame -> PNG sequence.
Verified over netdeath-20260708.fifodump: 12 frames, scene assembles draw by
draw (26->48->78->87->127 quads), frame 11 = coherent perspective-correct arena
interior (tiled floor to vanishing point, ceiling, side structures). This is
the dress rehearsal for the live DOSBox seam -- identical pipeline, wire from a
file instead of the C012 device.
FINDING: firmware is real-time-capable (3.7s), the CPU numpy per-poly render is
the bottleneck (69.9s/12 frames, ~5.8s/frame). The fix already exists: the
conformant GPU tile path (igc_gpu). Moving the per-draw raster onto it is the
M4b->M4c bridge to real-time. Full writeup in M4B-RESULTS.md.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
CydandClaude Opus 4.8