feat v1.32.0: polyline split, tool cursors, Esc walk-back in merge/split

- splitRoomPath in logic.ts: wall-to-wall polyline cut with interior
  vertices; validates wall crossings, self-intersection, degenerate
  parts; splitRoom delegates (2-point path); +3 unit tests (93 total)
- split UI: interior clicks add snapped intermediate points, live
  polyline + vertices + preview; new/updated toasts
- cursors: pointer for merge/delroom and split room-pick stage,
  crosshair while cutting (stage tool-* classes)
- Esc: split — drop last point, then room pick, then back to draw;
  merge — clear selection, then back to draw
- smoke_split_polyline.mjs (14 checks); TESTING/CHANGELOG same-commit

custom_components/houseplan/const.py

@@ -11,7 +11,7 @@ PLANS_DIR = "houseplan/plans"  # relative to the HA configuration directory
 FILES_URL = "/houseplan_files/files"
 FILES_DIR = "houseplan/files"
 CONF_ADMIN_ONLY = "admin_only"
-VERSION = "1.31.2"
+VERSION = "1.32.0"
 
 DEFAULT_CONFIG: dict = {
     "spaces": [],

custom_components/houseplan/manifest.json

@@ -16,5 +16,5 @@
   "issue_tracker": "https://github.com/Matysh/houseplan-card/issues",
   "requirements": [],
   "single_config_entry": true,
-  "version": "1.31.2"
+  "version": "1.32.0"
 }

demo/smoke_merge_highlight.mjs

@@ -14,7 +14,7 @@ const res = await page.evaluate(async () => {
   out.amberStroke = cs ? cs.stroke.includes('255, 193, 77') : null;
   out.amberFill = cs ? cs.fill.includes('255, 193, 77') : null;
   // split-выбор подсвечивается так же
-  c._mergeSel = null; c._tool = 'split'; c._splitSel = { roomId: room.id }; c.requestUpdate(); await c.updateComplete;
+  c._mergeSel = null; c._tool = 'split'; c._splitSel = { roomId: room.id, pts: [] }; c.requestUpdate(); await c.updateComplete;
   await new Promise((r) => setTimeout(r, 250));
   const el2 = [...sr().querySelectorAll('.room')].find((e) => e.classList.contains('picked'));
   out.splitPicked = !!el2 && getComputedStyle(el2).stroke.includes('255, 193, 77');

demo/smoke_split_polyline.mjs

@@ -0,0 +1,55 @@
+import { launch } from './serve.mjs';
+const { page, browser } = await launch();
+const res = await page.evaluate(async () => {
+  const out = {};
+  const c = window.__card;
+  const sr = () => c.shadowRoot || c.renderRoot;
+  const stage = () => sr().querySelector('.stage');
+  c._setMode('plan'); await c.updateComplete;
+  // 1) курсоры: split до выбора комнаты — pointer, после — crosshair; merge — pointer
+  c._tool = 'split'; c.requestUpdate(); await c.updateComplete;
+  out.splitPickCursor = getComputedStyle(stage()).cursor === 'pointer';
+  const rooms = c._spaceModel().rooms;
+  const room = rooms.find((r) => r.id === 'r1');
+  const center = c._roomCenter(room);
+  c._splitClick(center); await c.updateComplete;
+  out.roomPicked = c._splitSel?.roomId === 'r1';
+  out.splitCutCursor = getComputedStyle(stage()).cursor === 'crosshair';
+  c._tool = 'merge'; c._splitSel = null; c.requestUpdate(); await c.updateComplete;
+  out.mergeCursor = getComputedStyle(stage()).cursor === 'pointer';
+  // 2) полилинейный разрез: r1 = прямоугольник? возьмём его poly и построим Г-разрез
+  c._tool = 'split'; await c.updateComplete;
+  c._splitClick(center);
+  const poly = (() => { const r = rooms.find((x) => x.id === 'r1');
+    return r.poly ? r.poly : [[r.x, r.y], [r.x + r.w, r.y], [r.x + r.w, r.y + r.h], [r.x, r.y + r.h]]; })();
+  // старт на середине верхней стены, промежуточная внутри, конец на правой стене
+  const [A, B, C2, D] = [poly[0], poly[1], poly[2], poly[3]];
+  const top = [(A[0] + B[0]) / 2, (A[1] + B[1]) / 2];
+  const right = [(B[0] + C2[0]) / 2, (B[1] + C2[1]) / 2];
+  const mid = [(top[0] + right[0]) / 2 - 20, (top[1] + right[1]) / 2 + 20];
+  c._splitClick(top);
+  out.firstOnWall = c._splitSel?.pts.length === 1;
+  c._splitClick(mid);
+  out.midAdded = c._splitSel?.pts.length === 2;
+  c._splitClick(right);
+  out.dialogAfterCut = !!c._pendingSplit && c._roomDialog;
+  out.partsPolys = c._pendingSplit ? [c._pendingSplit.mainPoly.length, c._pendingSplit.newPoly.length] : null;
+  // отмена — комната целая
+  c._roomDialogCancel(); await c.updateComplete;
+  out.cancelKeepsRoom = !c._pendingSplit && rooms.length === c._spaceModel().rooms.length;
+  // 3) Esc: пошаговый выход
+  const esc = async () => { window.dispatchEvent(new KeyboardEvent('keydown', { key: 'Escape' })); await c.updateComplete; };
+  c._tool = 'split'; c._splitSel = null;
+  c._splitClick(center); c._splitClick(top); c._splitClick(mid); await c.updateComplete;
+  await esc(); out.escDropsPoint = c._splitSel?.pts.length === 1;
+  await esc(); out.escDropsFirst = c._splitSel?.pts.length === 0;
+  await esc(); out.escDropsRoom = c._splitSel === null && c._tool === 'split';
+  await esc(); out.escExitsTool = c._tool === 'draw';
+  // merge: выбор → Esc снимает, ещё Esc — выход
+  c._tool = 'merge'; c._mergeSel = 'r1'; await c.updateComplete;
+  await esc(); out.escClearsMerge = c._mergeSel === null && c._tool === 'merge';
+  await esc(); out.escExitsMerge = c._tool === 'draw';
+  return out;
+});
+console.log(JSON.stringify(res, null, 1));
+await browser.close();

docs/CHANGELOG.md

@@ -1,5 +1,15 @@
 # Changelog
 
+## v1.32.0 — 2026-07-22 (split polyline, tool cursors, Esc)
+- **Split can now cut along a polyline**, not just a straight chord: start on
+  a wall, click intermediate points inside the room, finish on another wall.
+  The path is validated (no wall crossings, no self-intersection) and drawn
+  live with vertices and a preview segment. Two clicks still work as before.
+- **Tool cursors**: Merge and delete-room show a pointer; Split shows a
+  pointer while picking the room, then a crosshair while cutting.
+- **Esc walks back out of Merge/Split** step by step: last cut point → first
+  point → room selection → back to the Draw tool. Merge: selection → tool.
+
 ## v1.31.2 — 2026-07-22
 - Plan editor: the room picked with the **Merge** tool (and the room selected
   for **Split**) is highlighted amber again. The `.outlined` markup style,

docs/TESTING.md

@@ -140,6 +140,12 @@ Run the *core flows* (marked ★ below) in each environment at least once per mi
       (explicit ripple color still wins); off/white lights unchanged [auto]
 - [ ] Alarm pulse (v1.27.0): leak/smoke/gas/CO/siren in 'on' pulse a red ring over any
       display mode; clears on 'off'; unavailable never alarms [auto]; reduced-motion static
+- [ ] Split polyline + cursors + Esc (v1.32.0): Merge shows a pointer cursor,
+      Split shows pointer until a room is picked then crosshair; the cut can be
+      a polyline — start on a wall, intermediate clicks inside the room, finish
+      on a wall (path drawn live, walls/self-crossing rejected); Esc walks back:
+      last cut point → room pick → back to the Draw tool (same for Merge:
+      selection → tool) [auto]
 - [ ] Merge/split pick highlight (v1.31.2): the first room clicked with the
       Merge tool (and the split-selected room) gets an amber outline + fill;
       visible over the blue markup outlines [auto]

package.json

@@ -1,6 +1,6 @@
 {
   "name": "houseplan-card",
-  "version": "1.31.2",
+  "version": "1.32.0",
   "description": "Interactive house plan Lovelace card for Home Assistant",
   "license": "MIT",
   "type": "module",

src/houseplan-card.ts

@@ -14,7 +14,7 @@ import {
 import {
   lqiColor, snapToGrid, samePoint, pointInPolygon, markerIdForBinding,
   segmentCm, formatLength, roomEdges, roomPoly, pointStrictlyInside, roomsOverlap,
-  pointOnBoundary, mergeRooms, splitRoom, polygonArea, closestPointOnBoundary,
+  pointOnBoundary, mergeRooms, splitRoomPath, polygonArea, closestPointOnBoundary, pointStrictlyInside as ptInside,
   snapToWall, openingAmount,
   averageLqi, fitView, declump, safeUrl, resolveTapAction, floorsOf, type FloorInfo,
   stateIcon, lightColorOf, isAlarmState, parseRoomRef, diffNewDevices,
@@ -32,7 +32,7 @@ import './space-card';
 import { cardStyles } from './styles';
 import { langOf, t, type I18nKey } from './i18n';
 
-const CARD_VERSION = '1.31.2';
+const CARD_VERSION = '1.32.0';
 const LS_KEY = 'houseplan_card_layout_v1';
 const LS_CFG = 'houseplan_card_cfg_v1'; // cache of the server config+layout for instant rendering
 const LS_ZOOM = 'houseplan_card_zoom_v1';
@@ -115,7 +115,7 @@ class HouseplanCard extends LitElement {
   private _openingInfo: OpeningCfg | null = null;
   private _opDrag: { id: string; moved: boolean } | null = null;
   private _mergeDialog: { aId: string; bId: string; poly: number[][]; pick: 'a' | 'b' } | null = null;
-  private _splitSel: { roomId: string; a: number[] | null } | null = null; // room being cut + first wall point
+  private _splitSel: { roomId: string; pts: number[][] } | null = null; // room being cut + the cut path so far
   // a split is applied only when the new room's dialog is confirmed — cancel leaves the room intact
   private _pendingSplit: { roomId: string; mainPoly: number[][]; newPoly: number[][] } | null = null;
   private _areaSel = '';
@@ -284,6 +284,27 @@ class HouseplanCard extends LitElement {
     if (this._tool === 'draw' && this._path.length) {
       e.preventDefault();
       this._undoPoint();
+      return;
+    }
+    if (!undo) return;
+    // Esc walks back out of merge/split: point by point, then the room pick,
+    // then the tool itself (back to the neutral draw tool)
+    if (this._tool === 'split') {
+      e.preventDefault();
+      if (this._splitSel?.pts?.length) {
+        this._splitSel = { ...this._splitSel, pts: this._splitSel.pts.slice(0, -1) };
+        if (!this._splitSel.pts.length) this._cursorPt = null;
+      } else if (this._splitSel) {
+        this._splitSel = null;
+      } else {
+        this._tool = 'draw';
+      }
+      return;
+    }
+    if (this._tool === 'merge') {
+      e.preventDefault();
+      if (this._mergeSel) this._mergeSel = null;
+      else this._tool = 'draw';
     }
   }
 
@@ -1451,7 +1472,7 @@ class HouseplanCard extends LitElement {
     if (!this._splitSel) {
       const hit = [...rooms].reverse().find((r) => this._pointInRoom(raw, r));
       if (!hit?.id) return;
-      this._splitSel = { roomId: hit.id, a: null };
+      this._splitSel = { roomId: hit.id, pts: [] };
       return;
     }
     const room = rooms.find((r) => r.id === this._splitSel!.roomId);
@@ -1469,16 +1490,30 @@ class HouseplanCard extends LitElement {
     const eps = this._gridPitch * 0.02;
     const pull = this._gridPitch * 6; // ≈2.5% of the plan width — generous but intentional
     const near = closestPointOnBoundary(raw, poly);
-    const pt = near && Math.hypot(near[0] - raw[0], near[1] - raw[1]) <= pull ? near : null;
+    const wallPt = near && Math.hypot(near[0] - raw[0], near[1] - raw[1]) <= pull ? near : null;
-    if (!pt || !pointOnBoundary(pt, poly, eps)) {
+    const onWall = !!wallPt && pointOnBoundary(wallPt, poly, eps);
-      this._showToast(this._t('toast.split_pick_wall'));
+    const cur = this._splitSel.pts;
+    if (!cur.length) {
+      // the cut starts on a wall
+      if (!onWall) {
+        this._showToast(this._t('toast.split_pick_wall'));
+        return;
+      }
+      this._splitSel = { ...this._splitSel, pts: [wallPt!] };
       return;
     }
-    if (!this._splitSel.a) {
+    if (!onWall) {
-      this._splitSel = { ...this._splitSel, a: pt };
+      // an interior click adds an intermediate vertex of the cut path
+      const mid = this._snap(raw);
+      if (!ptInside(mid, poly, eps)) {
+        this._showToast(this._t('toast.split_pick_inside'));
+        return;
+      }
+      this._splitSel = { ...this._splitSel, pts: [...cur, mid] };
       return;
     }
-    const parts = splitRoom(poly, this._splitSel.a, pt, eps);
+    // a wall point finishes the cut
+    const parts = splitRoomPath(poly, [...cur, wallPt!], eps);
     if (!parts) {
       this._showToast(this._t('toast.split_bad_cut'));
       return;
@@ -1501,7 +1536,7 @@ class HouseplanCard extends LitElement {
   private _markupMove(ev: MouseEvent): void {
     if (!this._markup) return;
     const drawing = this._tool === 'draw' && this._path.length && !this._contourClosed;
-    const cutting = this._tool === 'split' && !!this._splitSel?.a;
+    const cutting = this._tool === 'split' && !!this._splitSel?.pts?.length;
     if (!drawing && !cutting) return;
     this._cursorPt = this._snap(this._svgPoint(ev));
   }
@@ -2490,7 +2525,7 @@ class HouseplanCard extends LitElement {
         ${this._markup ? this._renderMarkupBar() : this._mode === 'devices' ? this._renderDevicesBar() : nothing}
         </div>
 
-        <div class="stage ${this._markup ? 'markup' : ''} ${space.bg ? '' : 'noplan'} mode-${this._mode}"
+        <div class="stage ${this._markup ? 'markup tool-' + this._tool + (this._tool === 'split' && !this._splitSel ? ' pickstage' : '') : ''} ${space.bg ? '' : 'noplan'} mode-${this._mode}"
           style="height:calc(100dvh - 118px)"
           @click=${(e: MouseEvent) => this._markupClick(e)}
           @wheel=${(e: WheelEvent) => this._onWheel(e)}
@@ -2822,7 +2857,8 @@ class HouseplanCard extends LitElement {
     if (!this._markup || !this._cursorPt) return null;
     if (this._tool === 'draw' && this._path.length && !this._contourClosed)
       return this._path[this._path.length - 1];
-    if (this._tool === 'split' && this._splitSel?.a) return this._splitSel.a;
+    if (this._tool === 'split' && this._splitSel?.pts?.length)
+      return this._splitSel.pts[this._splitSel.pts.length - 1];
     return null;
   }
 
@@ -3089,10 +3125,13 @@ class HouseplanCard extends LitElement {
             x2="${this._cursorPt[0]}" y2="${this._cursorPt[1]}"></line>`
         : nothing}
       ${path.map((p, i) => svg`<circle class="vertex ${i === 0 ? 'first' : ''}" cx="${p[0]}" cy="${p[1]}" r="${g * 0.22}"></circle>`)}
-      ${this._tool === 'split' && this._splitSel?.a
+      ${this._tool === 'split' && this._splitSel?.pts?.length
-        ? svg`<circle class="vertex first" cx="${this._splitSel.a[0]}" cy="${this._splitSel.a[1]}" r="${g * 0.22}"></circle>
+        ? svg`${this._splitSel.pts.length > 1
+              ? svg`<polyline class="pathline" points="${this._splitSel.pts.map((p) => p.join(',')).join(' ')}"></polyline>`
+              : nothing}
+            ${this._splitSel.pts.map((p, i) => svg`<circle class="vertex ${i === 0 ? 'first' : ''}" cx="${p[0]}" cy="${p[1]}" r="${g * 0.22}"></circle>`)}
             ${this._cursorPt
-              ? svg`<line class="preview" x1="${this._splitSel.a[0]}" y1="${this._splitSel.a[1]}"
+              ? svg`<line class="preview" x1="${this._splitSel.pts[this._splitSel.pts.length - 1][0]}" y1="${this._splitSel.pts[this._splitSel.pts.length - 1][1]}"
                   x2="${this._cursorPt[0]}" y2="${this._cursorPt[1]}"></line>`
               : nothing}`
         : nothing}

src/i18n/en.json

@@ -128,8 +128,8 @@
   "toast.room_overlap": "The outline overlaps room “{name}” — rooms must not overlap",
   "toast.merge_not_adjacent": "Only rooms that share a wall can be merged",
   "toast.rooms_merged": "Rooms merged into “{name}”",
-  "toast.split_pick_wall": "Click a grid dot on the room’s wall",
+  "toast.split_pick_wall": "Start the cut on the room’s wall",
-  "toast.split_bad_cut": "The cut must be a straight line from wall to wall, inside the room",
+  "toast.split_bad_cut": "The cut must run wall to wall inside the room, without crossing walls or itself",
   "merge.header": "Merge rooms",
   "merge.hint": "The merged room keeps one name and one area. The other area is released — its devices leave the plan until another room claims it.",
   "merge.keep": "Keep",
@@ -260,5 +260,6 @@
   "space.label_light": "Lights on/off",
   "roomcard.light_on": "On",
   "roomcard.light_off": "Off",
-  "roomcard.light_partial": "{on} of {total}"
+  "roomcard.light_partial": "{on} of {total}",
+  "toast.split_pick_inside": "Intermediate cut points must be inside the room"
 }

src/i18n/ru.json

@@ -128,8 +128,8 @@
   "toast.room_overlap": "Контур накладывается на комнату «{name}» — комнаты не должны накладываться",
   "toast.merge_not_adjacent": "Объединять можно только комнаты с общей стеной",
   "toast.rooms_merged": "Комнаты объединены в «{name}»",
-  "toast.split_pick_wall": "Кликните по узлу сетки на стене комнаты",
+  "toast.split_pick_wall": "Начните разрез на стене комнаты",
-  "toast.split_bad_cut": "Разрез — прямая от стены до стены внутри комнаты",
+  "toast.split_bad_cut": "Разрез — от стены до стены внутри комнаты, без пересечения стен и самого себя",
   "merge.header": "Объединение комнат",
   "merge.hint": "У объединённой комнаты одно имя и одна зона. Вторая зона освобождается — её устройства уйдут с плана, пока их не заберёт другая комната.",
   "merge.keep": "Оставить",
@@ -260,5 +260,6 @@
   "space.label_light": "Свет вкл/выкл",
   "roomcard.light_on": "Вкл",
   "roomcard.light_off": "Выкл",
-  "roomcard.light_partial": "{on} из {total}"
+  "roomcard.light_partial": "{on} из {total}",
+  "toast.split_pick_inside": "Промежуточные точки разреза — внутри комнаты"
 }

src/logic.ts

@@ -310,27 +310,50 @@ function dropRepeats(pts: number[][], eps: number): number[][] {
 export function splitRoom(
   poly: number[][], a: number[], b: number[], eps = 1e-6,
 ): [number[][], number[][]] | null {
-  if (!poly || poly.length < 3 || samePoint(a, b, eps)) return null;
+  return splitRoomPath(poly, [a, b], eps);
+}
+
+/**
+ * Split a room along a polyline: first and last points on walls, intermediate
+ * vertices strictly inside the room. A two-point path is the classic straight
+ * chord. Returns the two parts, or null when the path is not a clean cut.
+ */
+export function splitRoomPath(
+  poly: number[][], pts: number[][], eps = 1e-6,
+): [number[][], number[][]] | null {
+  if (!poly || poly.length < 3 || !pts || pts.length < 2) return null;
+  const a = pts[0];
+  const b = pts[pts.length - 1];
+  if (samePoint(a, b, eps)) return null;
   const ia = edgeIndexOf(poly, a, eps);
   const ib = edgeIndexOf(poly, b, eps);
   if (ia < 0 || ib < 0) return null;                       // an end is not on a wall
-  for (let i = 0; i < poly.length; i++)
+  const mids = pts.slice(1, -1);
-    if (segmentsProperlyCross(a, b, poly[i], poly[(i + 1) % poly.length])) return null; // leaves the room
+  for (const m of mids) if (!pointStrictlyInside(m, poly, eps)) return null;
-  // a chord lying along a wall has its midpoint ON the outline, not inside it
+  // no path segment may cross a wall
-  if (!pointStrictlyInside([(a[0] + b[0]) / 2, (a[1] + b[1]) / 2], poly, eps)) return null;
+  for (let sI = 0; sI < pts.length - 1; sI++)
+    for (let i = 0; i < poly.length; i++)
+      if (segmentsProperlyCross(pts[sI], pts[sI + 1], poly[i], poly[(i + 1) % poly.length])) return null;
+  // the path may not properly self-intersect
+  for (let sI = 0; sI < pts.length - 1; sI++)
+    for (let t = sI + 2; t < pts.length - 1; t++)
+      if (segmentsProperlyCross(pts[sI], pts[sI + 1], pts[t], pts[t + 1])) return null;
+  // a straight chord lying along a wall has its midpoint ON the outline, not inside
+  if (pts.length === 2 && !pointStrictlyInside([(a[0] + b[0]) / 2, (a[1] + b[1]) / 2], poly, eps))
+    return null;
   const walk = (from: number[], fromIdx: number, to: number[], toIdx: number): number[][] => {
-    const pts: number[][] = [from];
+    const acc: number[][] = [from];
     let i = (fromIdx + 1) % poly.length;
     for (let guard = 0; guard <= poly.length; guard++) {
-      pts.push(poly[i]);
+      acc.push(poly[i]);
       if (i === toIdx) break;
       i = (i + 1) % poly.length;
     }
-    pts.push(to);
+    acc.push(to);
-    return dropRepeats(pts, eps);
+    return dropRepeats(acc, eps);
   };
-  const p1 = walk(a, ia, b, ib);
+  const p1 = dropRepeats([...walk(a, ia, b, ib), ...[...mids].reverse()], eps);
-  const p2 = walk(b, ib, a, ia);
+  const p2 = dropRepeats([...walk(b, ib, a, ia), ...mids], eps);
   if (p1.length < 3 || p2.length < 3) return null;
   if (polygonArea(p1) <= eps || polygonArea(p2) <= eps) return null;
   return [p1, p2];

src/styles.ts

@@ -445,6 +445,12 @@ export const cardStyles = css`
     .stage.markup {
       cursor: crosshair;
     }
+    /* room-picking stages: merge (both clicks) and split before a room is chosen */
+    .stage.markup.tool-merge,
+    .stage.markup.tool-split.pickstage,
+    .stage.markup.tool-delroom {
+      cursor: pointer;
+    }
     .stage.markup .room {
       pointer-events: none;
     }

test/logic.test.mjs

@@ -3,6 +3,7 @@ import assert from 'node:assert/strict';
 import {
   lqiColor, snapToGrid, segKey, samePoint, pointInPolygon, markerIdForBinding, averageLqi,
   fitView, declump, safeUrl, resolveTapAction, floorsOf, subst, spaceDisplayOf, roomFillColor,
+  splitRoomPath,
   segmentCm, formatLength, roomEdges, roomPoly, pointOnBoundary, pointStrictlyInside, roomsOverlap,
   mergeRooms, splitRoom, polygonArea, closestPointOnBoundary, isActiveState, snapToWall, openingAmount, fillColorsOf, lerpColor, roomFillStyle, stateIcon, lightColorOf, isAlarmState, parseRoomRef, diffNewDevices,
 } from '../test-build/logic.js';
@@ -544,3 +545,38 @@ test('spaceDisplayOf: room-card metric flags default to off', () => {
   const d1 = spaceDisplayOf({ plan_url: 'x', settings: { label_temp: true, label_light: true } });
   assert.deepEqual([d1.labelTemp, d1.labelHum, d1.labelLqi, d1.labelLight], [true, false, false, true]);
 });
+
+test('splitRoomPath: polyline cut of a square', () => {
+  const sq = [[0, 0], [10, 0], [10, 10], [0, 10]];
+  // Г-образный разрез: верхняя стена (4,0) → внутрь (4,6) → правая стена (10,6)
+  const parts = splitRoomPath(sq, [[4, 0], [4, 6], [10, 6]], 1e-6);
+  assert.ok(parts);
+  const [p1, p2] = parts;
+  const area = (p) => Math.abs(p.reduce((a, _, i) => {
+    const [x1, y1] = p[i], [x2, y2] = p[(i + 1) % p.length];
+    return a + x1 * y2 - x2 * y1;
+  }, 0)) / 2;
+  assert.ok(Math.abs(area(p1) + area(p2) - 100) < 1e-6);
+  // меньшая часть — прямоугольник 6x6 минус... фактически площадь 4*6+... проверим что обе > 0
+  assert.ok(area(p1) > 0 && area(p2) > 0);
+});
+
+test('splitRoomPath: two points == classic straight chord', () => {
+  const sq = [[0, 0], [10, 0], [10, 10], [0, 10]];
+  const parts = splitRoomPath(sq, [[5, 0], [5, 10]], 1e-6);
+  assert.ok(parts);
+});
+
+test('splitRoomPath rejects bad paths', () => {
+  const sq = [[0, 0], [10, 0], [10, 10], [0, 10]];
+  // промежуточная точка снаружи
+  assert.equal(splitRoomPath(sq, [[4, 0], [4, -3], [10, 6]], 1e-6), null);
+  // сегмент пересекает стену (выходит и возвращается)
+  assert.equal(splitRoomPath(sq, [[4, 0], [14, 5], [10, 6]], 1e-6), null);
+  // конец не на стене
+  assert.equal(splitRoomPath(sq, [[4, 0], [5, 5]], 1e-6), null);
+  // самопересечение пути
+  assert.equal(splitRoomPath(sq, [[2, 0], [8, 8], [8, 2], [2, 8], [0, 4]], 1e-6), null);
+  // менее двух точек
+  assert.equal(splitRoomPath(sq, [[4, 0]], 1e-6), null);
+});