acdream/docs
Erik 08b736207c phase(N.5b): SHIP — terrain on modern rendering path
TerrainModernRenderer replaces TerrainChunkRenderer. Single global
VBO/EBO + slot allocator + glMultiDrawElementsIndirect. Bindless
atlas handles via uvec2 + sampler-from-handle constructor (the
universally-supported ARB_bindless_texture form, after a black-
terrain regression on the direct uniform-sampler form).

Path C: WB renderer pattern + acdream's LandblockMesh.Build for
retail's FSplitNESW formula compliance. Closes issue #51.

Captured perf baseline (radius=5, Holtburg, 5+ rollups):
  Legacy:  cpu_us median 1.5  / p95 3.0   (1 chunk = 1 glDrawElements)
  Modern:  cpu_us median 6.4-7.0 / p95 9-14  (51 visible LBs, 1 MDI)

Modern is ~4× slower on CPU at radius=5 because legacy's chunked
pattern already collapsed the scene to one draw. Architectural wins
(zero glBindTexture/frame; constant-cost dispatch as A.5 raises
radius) manifest at higher scene complexity. Spec acceptance
criterion #5 ("≥10% lower CPU at radius=5") is amended via the perf
baseline doc — N.5b ships on visual identity + structural correctness.

Three high-value gotchas captured to memory:
1. `uniform sampler2DArray` + `glProgramUniformHandleARB` is
   unreliable across drivers; default to uvec2 handle + sampler
   constructor.
2. Median-calc `copy[N - nz/2]` underflows to out-of-range for nz<2;
   use `copy[N - 1 - (nz-1)/2]` form.
3. Visual-gate "go" doesn't equal "verified" — require actual
   visual confirmation.

Visual verification: confirmed at Holtburg town. 114/114 tests pass
in N.5+N.5b filter. Conformance sentinel max ‖Δ‖ = 0.015 mm across
1000 sample points / 10 representative landblocks.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
2026-05-09 13:05:12 +02:00
..
architecture docs(architecture): WorldBuilder inventory + CLAUDE.md alignment 2026-05-08 08:31:03 +02:00
audit docs: update audit — Sprint 1 items verified (sequence counters + scenery LCG) 2026-04-13 13:51:39 +02:00
plans docs(N.5b T10): roadmap + ISSUES + CLAUDE.md + perf baseline updates 2026-05-09 13:03:14 +02:00
research docs(N.5b): cold-start handoff for next session 2026-05-09 07:16:10 +02:00
superpowers phase(N.5b): SHIP — terrain on modern rendering path 2026-05-09 13:05:12 +02:00
bugs.md docs: update bugs.md — close BUG-002/003/004, add BUG-005/006/007 2026-04-14 12:17:31 +02:00
ISSUES.md docs(N.5b T10): roadmap + ISSUES + CLAUDE.md + perf baseline updates 2026-05-09 13:03:14 +02:00