pathways: four directions lead to four distinct photos - dedupe per-photo next ids in exit generation (server), exclude other directions' targets from placement candidates (client)

3 files changed, 15 insertions, 5 deletions

diff --git a/public/app.js b/public/app.js
index e4fa727..98dcaed 100644
--- a/public/app.js
+++ b/public/app.js
@@ -253,9 +253,11 @@ function choosePlacement(id, dir) {
   if (!ex) return null
   const from = tiles.get(id).rect
   const seen = new Set()
+  const claimed = new Set()
+  if (exits) for (const e of exits) if (e.dir !== dir && e.next) claimed.add(e.next.id)
   const candIds = []
   const addCand = (cid) => {
-    if (cid && !seen.has(cid) && !rectOf.has(cid)) {
+    if (cid && !claimed.has(cid) && !seen.has(cid) && !rectOf.has(cid)) {
       seen.add(cid)
       candIds.push(cid)
     }
diff --git a/public/index.html b/public/index.html
index 51e3ef3..1134334 100644
--- a/public/index.html
+++ b/public/index.html
@@ -5,7 +5,7 @@
   <meta name="viewport" content="width=device-width, initial-scale=1">
   <meta name="color-scheme" content="dark">
   <title>pathways</title>
-  <link rel="stylesheet" href="/app.css?v=9">
+  <link rel="stylesheet" href="/app.css?v=10">
 </head>
 <body>
   <main id="stage">
@@ -16,6 +16,6 @@
     <p>four paths, one per direction. walk them.<br><span class="hint">drag or scroll to pan · pinch to zoom · double-click empty space or press 0 to fit</span></p>
     <button id="start">start</button>
   </div>
-  <script src="/app.js?v=9"></script>
+  <script src="/app.js?v=10"></script>
 </body>
 </html>
diff --git a/server.mjs b/server.mjs
index 6659426..b73c44e 100644
--- a/server.mjs
+++ b/server.mjs
@@ -119,6 +119,7 @@ async function load() {
     const chosen = own.slice(0, 4)
     while (chosen.length < 4) chosen.push(library)
     const used = new Map()
+    const usedNext = new Set()
     const list = []
     for (let i = 0; i < 4; i++) {
       const p = chosen[i]
@@ -129,11 +130,18 @@ async function load() {
       const start = (idx + 1 + step) % cyc.length
       const walk = []
       for (let k = 0; k < 60 && walk.length < cyc.length; k++) walk.push(cyc[(start + k) % cyc.length])
+      let nextId = cyc[start]
+      for (const wid of walk) {
+        if (wid !== pid && !usedNext.has(wid)) { nextId = wid; break }
+      }
+      usedNext.add(nextId)
+      const wi = walk.indexOf(nextId)
+      const rot = wi > 0 ? walk.slice(wi).concat(walk.slice(0, wi)) : walk
       list.push({
         dir: DIRS[i],
         path: { type: p.type, name: p.name, count: p.count },
-        nextId: cyc[start],
-        walk,
+        nextId,
+        walk: rot,
       })
     }
     exits.set(pid, list)