initial seed: retrofit campaign lineage from local working trees

panvk-bifrost campaigns (r1..r4 Vulkan compositor + r5.video1 Vulkan video decode) shipped before this repo existed; the deliverable patches live in marfrit-packages, but the reasoning chain, phase docs, and source-state evidence lived only in local working trees on the development host. This retrofit imports: - mesa-panvk-bifrost/ — r1..r4 era phase docs (iter1..iter18) (libmali stub blobs at iter18/blob/ excluded — 109MB of RE artifacts replaced with a README pointer) - mesa-panvk-bifrost-video/ — sibling campaign phase docs + probe - evidence/ — frozen .tgz source snapshots at each milestone (basis for the 0005 patch diff generation) Future iterations should branch off here from day one, so each iter is a commit rather than a snapshot. See [[feedback-session-local-process-pins]] for the process drift this retrofit closes. Total: 1.9 MB across 124 files. Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>
2026-05-23 05:25:37 +02:00
parent 430d0da278
commit a4e7d8ab90
124 changed files with 22551 additions and 1 deletions
@@ -0,0 +1,73 @@
+iter5 vertex+UBO probe — captured 2026-05-19 on ohm
+(PineTab2 v2.0, RK3566, Mali-G52 r1 MC1, Mesa 26.0.6, kernel 7.0.0-danctnix1-6)
+
+Source: panvk-bifrost/iter5/{probe_vbo_ubo.c, .vert, .frag, Makefile}
+Deployed to: /tmp/panvk-iter5/
+
+===== RUN #1 (baseline) =====
+[step] vkCreateInstance
+WARNING: panvk is not a conformant Vulkan implementation, testing use only.
+[info] gpu='Mali-G52 r1 MC1'
+[step] vkCreateDevice
+[step] vkCreateBuffer vertex buffer
+[step] vkCreateBuffer UBO
+[step] vkCreateDescriptorSetLayout (UBO @ vertex)
+[step] vkCreatePipelineLayout + shaders
+[step] vkCreateGraphicsPipelines
+[step] record cmd buffer
+[step] submit + wait
+[step] verify
+[info] center (32,28) = 0xff5d564c  (R=4c G=56 B=5d)
+[info] TL=0x00000000 TR=0x00000000
+[info] covered (non-clear) pixels = 338 / 4096
+[PASS]
+
+===== RUN #2 (VK_LAYER_KHRONOS_validation) =====
+[no validation warnings]
+covered = 338   [PASS]
+
+===== STABILITY: 5 reruns =====
+covered = 338   [PASS]   x5
+
+7/7 PASS after coverage-range fix.
+
+===== INITIAL FAILURE NOTE =====
+
+First run reported "coverage out of range: 338 (want 800..1600)" — that was a
+verification-side arithmetic error on my (claude-noether's) part, not a driver
+issue. Triangle area = 0.5 * 0.8 * 0.8 = 0.32 sq units in NDC; viewport area
+is 4 sq units, so 8% coverage = ~328 pixels. The driver produced exactly 338,
+which matches the expected coverage within edge-rule tolerance.
+
+Substantive PASS criteria (interpolated center color, clear corners) were
+satisfied on the first run; only the loose coverage-range check needed
+calibration. Fixed in-tree at `iter5/probe_vbo_ubo.c`.
+
+===== KEY OBSERVATIONS =====
+
+1. Vertex input binding works:
+     binding 0: stride 32, INPUT_RATE_VERTEX
+     attribute 0: R32G32_SFLOAT, offset 0 (pos)
+     attribute 1: R32G32B32_SFLOAT, offset 16 (color)
+   GPU correctly fetched both attributes from the bound vertex buffer.
+
+2. UBO binding at vertex stage works:
+     mat4 transform with scale 0.8 in x/y was correctly applied.
+     Triangle vertices at NDC (-0.5,-0.5)/(0.5,-0.5)/(0,0.5) scaled to
+     (-0.4,-0.4)/(0.4,-0.4)/(0,0.4) — visible from the 338-pixel coverage
+     (matches 0.8-scaled area, NOT unscaled 0.5-scaled area which would be
+     ~500 pixels).
+
+3. Varying interpolation works:
+     center pixel at (32, 28) has R=0x4c G=0x56 B=0x5d. All three vertex
+     colors (red/green/blue) contributed via barycentric interpolation —
+     none of the channels are zero, none are saturated, all are in a
+     reasonable middle-of-range value.
+
+4. Bifrost vertex-side descriptor model handles UBO + vertex-stage shader
+   correctly (the headline hypothesis for this iter — that vertex-stage
+   descriptor binding would fail on Bifrost — did not materialize).
+
+5. Deterministic across runs: identical 338 covered pixels each time.
+
+No GPU faults, no validation warnings, all 7 runs identical.