From ccf77c988ab0632ff67224a495c8446a081b6e65 Mon Sep 17 00:00:00 2001
From: CNCKitchen <stefan.elitz@gmail.com>
Date: Thu, 2 Apr 2026 15:14:53 +0200
Subject: [PATCH] feat: increase triangle safety cap to 20M and enhance
 progress reporting during subdivision

---
 index.html        |  4 ++--
 js/i18n.js        |  6 ++++--
 js/main.js        |  7 ++++++-
 js/subdivision.js | 18 ++++++++++++++++--
 4 files changed, 28 insertions(+), 7 deletions(-)

diff --git a/index.html b/index.html
index 5588b74..990a9e1 100644
--- a/index.html
+++ b/index.html
@@ -328,11 +328,11 @@
         </div>
         <div class="form-row slider-row">
           <label for="max-triangles" data-i18n="labels.outputTriangles" data-i18n-title="tooltips.outputTriangles" title="Mesh is fully subdivided first, then decimated down to this count">Output Triangles</label>
-          <input type="range" id="max-triangles" min="10000" max="10000000" step="10000" value="1000000" />
+          <input type="range" id="max-triangles" min="10000" max="20000000" step="10000" value="1000000" />
           <span class="val" id="max-triangles-val">1.0 M</span>
         </div>
         <div id="tri-limit-warning" class="tri-limit-warning hidden" data-i18n="warnings.safetyCapHit">
-          ⚠ 10M-triangle safety cap hit during subdivision — result may still be coarser than requested edge length.
+          ⚠ 20M-triangle safety cap hit during subdivision — result may still be coarser than requested edge length.
         </div>
 
         <div id="export-progress" class="export-progress hidden">
diff --git a/js/i18n.js b/js/i18n.js
index 102e8d0..a57d00f 100644
--- a/js/i18n.js
+++ b/js/i18n.js
@@ -120,11 +120,12 @@ export const TRANSLATIONS = {
     'tooltips.resolution':           'Edges longer than this value will be split during export',
     'labels.outputTriangles':        'Output Triangles',
     'tooltips.outputTriangles':      'Mesh is fully subdivided first, then decimated down to this count',
-    'warnings.safetyCapHit':         '\u26a0 10M-triangle safety cap hit during subdivision \u2014 result may still be coarser than requested edge length.',
+    'warnings.safetyCapHit':         '\u26a0 20M-triangle safety cap hit during subdivision \u2014 result may still be coarser than requested edge length.',
     'ui.exportStl':                  'Export STL',
 
     // Export progress stages
     'progress.subdividing':          'Subdividing mesh\u2026',
+    'progress.refining':             'Refining: {cur} triangles, longest edge {edge}',
     'progress.applyingDisplacement': 'Applying displacement to {n} triangles\u2026',
     'progress.displacingVertices':   'Displacing vertices\u2026',
     'progress.decimatingTo':         'Simplifying {from} \u2192 {to} triangles\u2026',
@@ -278,11 +279,12 @@ export const TRANSLATIONS = {
     'tooltips.resolution':           'Kanten l\u00e4nger als dieser Wert werden beim Export unterteilt',
     'labels.outputTriangles':        'Max Dreiecke',
     'tooltips.outputTriangles':      'Das Netz wird zuerst vollst\u00e4ndig unterteilt, dann auf diese Anzahl dezimiert',
-    'warnings.safetyCapHit':         '\u26a0 10-Mio.-Dreiecke-Sicherheitsgrenze bei der Unterteilung erreicht \u2014 Ergebnis kann gr\u00f6ber als gew\u00fcnschte Kantenl\u00e4nge sein.',
+    'warnings.safetyCapHit':         '\u26a0 20-Mio.-Dreiecke-Sicherheitsgrenze bei der Unterteilung erreicht \u2014 Ergebnis kann gr\u00f6ber als gew\u00fcnschte Kantenl\u00e4nge sein.',
     'ui.exportStl':                  'STL exportieren',
 
     // Export progress stages
     'progress.subdividing':          'Netz wird verfeinert\u2026',
+    'progress.refining':             'Verfeinern: {cur} Dreiecke, l\u00e4ngste Kante {edge}',
     'progress.applyingDisplacement': 'Textur auf {n} Dreiecke anwenden\u2026',
     'progress.displacingVertices':   'Punkte werden verschoben\u2026',
     'progress.decimatingTo':         '{from} \u2192 {to} Dreiecke vereinfachen\u2026',
diff --git a/js/main.js b/js/main.js
index 993cc8e..acfb0a1 100644
--- a/js/main.js
+++ b/js/main.js
@@ -1701,7 +1701,12 @@ async function handleExport() {
 
     const { geometry: subdivided, safetyCapHit } = await subdivide(
       currentGeometry, settings.refineLength,
-      (p) => setProgress(0.02 + p * 0.35, t('progress.subdividing')),
+      (p, triCount, longestEdge) => {
+        const label = triCount != null
+          ? t('progress.refining', { cur: triCount.toLocaleString(), edge: longestEdge.toFixed(2) })
+          : t('progress.subdividing');
+        setProgress(0.02 + p * 0.35, label);
+      },
       faceWeights
     );
 
diff --git a/js/subdivision.js b/js/subdivision.js
index 465996b..37b6ad7 100644
--- a/js/subdivision.js
+++ b/js/subdivision.js
@@ -15,7 +15,7 @@
 import * as THREE from 'three';
 
 const QUANTISE   = 1e4;
-const SAFETY_CAP = 10_000_000; // absolute OOM guard
+const SAFETY_CAP = 20_000_000; // absolute OOM guard
 
 // ── Public entry point ───────────────────────────────────────────────────────
 
@@ -59,6 +59,19 @@ export async function subdivide(geometry, maxEdgeLength, onProgress, faceWeights
       break;
     }
 
+    // Find longest edge for progress reporting
+    let maxEdgeLenSq = 0;
+    for (let t = 0; t < currentIndices.length; t += 3) {
+      const a = currentIndices[t], b = currentIndices[t + 1], c = currentIndices[t + 2];
+      const ab = edgeLenSq(positions, a, b);
+      const bc = edgeLenSq(positions, b, c);
+      const ca = edgeLenSq(positions, c, a);
+      if (ab > maxEdgeLenSq) maxEdgeLenSq = ab;
+      if (bc > maxEdgeLenSq) maxEdgeLenSq = bc;
+      if (ca > maxEdgeLenSq) maxEdgeLenSq = ca;
+    }
+    const longestEdge = Math.sqrt(maxEdgeLenSq);
+
     const { newIndices, newFaceExcluded, newFaceParentId, changed } = subdividePass(
       positions, normals, weights, currentIndices, maxEdgeLength, SAFETY_CAP, currentFaceExcluded,
       canonIdx, posCanonMap, currentFaceParentId
@@ -69,7 +82,8 @@ export async function subdivide(geometry, maxEdgeLength, onProgress, faceWeights
 
     if (newIndices.length / 3 >= SAFETY_CAP) safetyCapHit = true;
 
-    if (onProgress) onProgress(Math.min(0.95, (iter + 1) / maxIterations));
+    const newTriCount = newIndices.length / 3;
+    if (onProgress) onProgress(Math.min(0.95, (iter + 1) / maxIterations), newTriCount, longestEdge);
     await new Promise(r => setTimeout(r, 0));
     if (!changed || safetyCapHit) break;
   }