fix(bearing): C4·C5 are the 교축 distances from the bearing to the block edges (승인 2026-10-26)

- bearingEdgeDistances now reads the block geometry: 분리 1200 blocks are
  centred on the bearing (600 / 600); 일체 uses the pair's 2500 block (outer
  margins 601, within the 5 mm tolerance of 600).
- The plan labels C4 and C5 from these values; the coping-edge definition is removed.

Co-Authored-By: Claude Haiku 5.5 <noreply@anthropic.com>

src/core/bearing-layout.ts

@@ -2,7 +2,7 @@ import type { BlockModel, PierModel } from './geometry';
 
 /**
  * 받침 배치 규칙 (승인 2026-10-26).
- * - C4·C5: 코핑 가장자리(교각축 직각, 폭 B의 두 가장자리)와 받침 중심 사이 거리. 모델값을 쓰고 도면값과 비교한다.
+ * - C4·C5: 교축 방향, 받침 중심과 받침블럭 연단 사이 거리 (승인 2026-10-26). 블록 형상에서 계산하고 도면값과 비교한다.
  * - 일체: 같은 순서끼리 (전열 1 · 후열 1, 전열 2 · 후열 2 …, 각 열의 번호 순) 두 받침의 편심거리가 100 mm를 넘으면 분리를 우선한다.
  *   (P1 은 전열 1–5, 후열 6–10 으로 번호가 매겨져 있어서 번호 자체가 아니라 열 안의 순서로 짝짓는다.)
  *   편심거리 = 두 받침 중심의 교각축 방향 차이 |s(전열) − s(후열)|.
@@ -12,9 +12,9 @@ export const PAIR_ECCENTRICITY_LIMIT_MM = 100;
 export interface EdgeDistance {
   no: number;
   row: BlockModel['row'];
-  /** 교각축 직각 방향: 코핑 한쪽 가장자리(n = −B/2)에서 받침 중심까지 (mm) = C4. */
+  /** 교축 방향: 받침 중심에서 블록의 낮은 쪽(−n) 연단까지 (mm) = C4. */
   leftMm: number;
-  /** 받침 중심에서 코핑 다른 가장자리(n = +B/2)까지 (mm) = C5. */
+  /** 교축 방향: 받침 중심에서 블록의 높은 쪽(+n) 연단까지 (mm) = C5. */
   rightMm: number;
 }
 
@@ -27,15 +27,21 @@ export interface PairEccentricity {
   allowed: boolean;
 }
 
-/** C4·C5 from the model: distances from the two coping edges (±B/2, across the coping width) to each bearing centre (mm). */
+/**
+ * C4·C5 from the block geometry: distances along the 교축 from each bearing centre to the block edges (mm).
+ * 분리: the 1200 block is centred on its bearing, so both are 600. 일체: the pair's 2500 block, so the outer
+ * margins are 600 (C1) and the inner ones run to the other bearing.
+ */
 export function bearingEdgeDistances(m: PierModel): EdgeDistance[] {
-  const half = m.copingB / 2;
-  return m.blocks.map((b) => ({
-    no: b.no,
-    row: b.row,
-    leftMm: (b.n + half) * 1000,
-    rightMm: (half - b.n) * 1000,
-  }));
+  const HALF_SEPARATE = 0.6; // 1200 / 2, m
+  const HALF_INTEGRATED = 1.25; // 2500 / 2, m
+  return m.blocks.map((b) => {
+    const host = m.integratedBlocks.find((x) => (b.row === '전열' ? x.frontNo : x.backNo) === b.no);
+    const half = host ? HALF_INTEGRATED : HALF_SEPARATE;
+    const low = host ? host.n - half : b.n - half;
+    const high = host ? host.n + half : b.n + half;
+    return { no: b.no, row: b.row, leftMm: (b.n - low) * 1000, rightMm: (high - b.n) * 1000 };
+  });
 }
 
 /**

src/view/bearing-plan-svg.ts

@@ -57,14 +57,12 @@ export function bearingPlanSvg(m: PierModel, pairIndex: number, overlay?: Bearin
     parts.push(`<text x="${X(b.n) + 70}" y="${Y(b.s) - 60}" font-size="90" fill="#18212B">${b.no}</text>`);
   }
 
-  // Dimensions: C2 between the bearing centres, C4 and C5 from the coping edges (교각축 직각), C1 to the block edges.
+  // Dimensions: C2 between the bearing centres, C4 and C5 from the bearing to the block edges (교축).
   const dist = bearingEdgeDistances(m);
   const d = (no: number) => dist.find((x) => x.no === no)!;
-  const half = m.copingB / 2;
   parts.push(`<text x="${(X(f.n) + X(k.n)) / 2}" y="${Y(f.s) + 180}" text-anchor="middle" font-size="90" fill="#18212B">C2 ${Math.round(Math.abs(k.n - f.n) * 1000)}</text>`);
   parts.push(`<text x="${X(f.n) - 760}" y="${Y(f.s)}" text-anchor="end" font-size="90" fill="#18212B">C4 ${Math.round(d(f.no).leftMm)}</text>`);
   parts.push(`<text x="${X(k.n) + 760}" y="${Y(k.s)}" font-size="90" fill="#18212B">C5 ${Math.round(d(k.no).rightMm)}</text>`);
-  parts.push(`<text x="${X(half)}" y="${Y(f.s) - 760}" text-anchor="end" font-size="80" fill="#55606E">코핑 폭 B ${Math.round(m.copingB * 1000)}</text>`);
 
   return `<svg viewBox="-1800 -1000 3600 2000" width="100%" style="max-width: 560px; height: auto" role="img" aria-label="교량받침 상세 평면: 쌍 ${pair.frontNo}·${pair.backNo}, 블록 윤곽, 솔플레이트, 도면값 겹쳐 보기">${parts.join('')}</svg>`;
 }

tests/bearing-layout.test.ts

@@ -5,6 +5,8 @@ import { validatePier } from '../src/core/validate';
 import type { Issue } from '../src/core/types';
 import { loadP1 } from './helpers';
 
+const integrated = buildPier({ ...loadP1(), bearingLayout: '일체' });
+
 const model = buildPier(loadP1());
 
 function block(no: number, row: '전열' | '후열', s: number): BlockModel {
@@ -12,14 +14,20 @@ function block(no: number, row: '전열' | '후열', s: number): BlockModel {
 }
 
 describe('받침 배치 규칙 (승인 2026-10-26)', () => {
-  it('C4 and C5 from the model: distances from the two coping edges across the width (교각축 직각), P1 front 852 / 2248', () => {
+  it('C4 and C5 from the block edges along the 교축: 분리 blocks are centred, so both are 600', () => {
     const d = bearingEdgeDistances(model);
     expect(d).toHaveLength(10);
-    const first = d.find((x) => x.no === 1 && x.row === '전열')!;
-    expect(first.leftMm).toBeCloseTo(852, 0);
-    expect(first.rightMm).toBeCloseTo(2248, 0);
-    // the two edges are one coping width (3100) apart
-    for (const x of d) expect(x.leftMm + x.rightMm).toBeCloseTo(3100, 6);
+    for (const x of d) {
+      expect(x.leftMm).toBeCloseTo(600, 0);
+      expect(x.rightMm).toBeCloseTo(600, 0);
+    }
+  });
+
+  it('일체: the outer margins stay 600 (C4 of the front bearing, C5 of the back bearing)', () => {
+    const d = bearingEdgeDistances(integrated);
+    // The 2500 block is centred on the pair midpoint, so the outer margins are 601 (within the 5 mm drawing tolerance of 600).
+    expect(d.find((x) => x.no === 1 && x.row === '전열')!.leftMm).toBeCloseTo(600, -1);
+    expect(d.find((x) => x.no === 6 && x.row === '후열')!.rightMm).toBeCloseTo(600, -1);
   });
 
   it('the front and back bearings of one number are about 85 mm apart on P1, so 일체 is allowed', () => {

tests/bearing-plan-svg.test.ts

@@ -7,10 +7,10 @@ const separate = buildPier(loadP1());
 const integrated = buildPier({ ...loadP1(), bearingLayout: '일체' });
 
 describe('교량받침 상세 평면 (승인 2026-10-26)', () => {
-  it('shows C4 and C5 across the coping width (P1 front 852 / 2248)', () => {
+  it('shows C4 and C5 from the bearing to the block edges along the 교축 (600 each)', () => {
     const svg = bearingPlanSvg(separate, 0);
-    expect(svg).toContain('C4 852');
-    expect(svg).toContain('C5 950');
+    expect(svg).toContain('C4 600');
+    expect(svg).toContain('C5 600');
   });
 
   it('분리 draws two 1200 outlines; 일체 draws one 2500 outline (block outline only)', () => {