Refactor code structure for improved readability and maintainability

LICENSE

@@ -0,0 +1,21 @@
+MIT License
+
+Copyright (c) 2026 CNCKitchen (Stefan Elitz)
+
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in all
+copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+SOFTWARE.

README.md

@@ -0,0 +1,62 @@
+# STL Texturizer
+
+A browser-based tool for applying surface displacement textures to STL files — no installation required.
+
+Load any `.stl` file, pick a texture, tune the parameters, and export a new displaced STL ready for slicing.
+
+## Features
+
+- **Texture presets** — 12 built-in seamless textures (basket, brick, bubble, crystal, hexagon, knitting, knurling, leather, weave, wood, noise, and more)
+- **Custom textures** — upload your own image as a displacement map
+- **Projection modes** — Triplanar, Cubic (Box), Cylindrical, Spherical, Planar XY/XZ/YZ
+- **UV transform** — independent U/V scale, offset, and rotation controls
+- **Displacement amplitude** — fine-tune depth from subtle grain to deep relief
+- **Surface mask** — skip horizontal top/bottom faces to keep flat surfaces clean
+- **Surface exclusions / inclusions** — paint individual faces with a brush or bucket-fill to exclude or exclusively include them from displacement
+- **Live preview** — real-time textured 3D preview with orbit/pan/zoom controls
+- **Mesh subdivision** — auto-subdivides coarse geometry before displacement for smoother results
+- **Export** — downloads a new binary STL with displacement baked in
+- **Light / Dark theme** — persisted per browser
+- **Multilingual** — English and German UI
+
+## Usage
+
+1. Open `index.html` in a modern browser (Chrome, Edge, Firefox, Safari).
+2. Drop an STL file onto the viewport or click **Load STL…**.
+3. Select a texture preset from the sidebar (or upload a custom image).
+4. Adjust projection mode, UV scale, offset, rotation, and amplitude.
+5. Optionally mask or exclude surfaces with the brush/fill tools.
+6. Click **Export STL** to download the displaced mesh.
+
+> **Note:** All processing runs entirely in the browser — no data is uploaded to any server.
+
+## Project Structure
+
+```
+index.html          # Main entry point
+style.css           # Styles (light/dark theme)
+textures/           # Built-in JPG displacement map images
+js/
+  main.js           # App bootstrap & UI wiring
+  viewer.js         # Three.js scene / camera / controls
+  stlLoader.js      # Binary & ASCII STL parser
+  presetTextures.js # Built-in texture presets + custom upload
+  previewMaterial.js# Three.js material for live preview
+  mapping.js        # UV projection logic
+  displacement.js   # Vertex displacement baking
+  subdivision.js    # Mesh subdivision
+  decimation.js     # QEM mesh decimation
+  exclusion.js      # Face exclusion / inclusion painting
+  exporter.js       # Binary STL export
+  i18n.js           # Translations (EN / DE)
+```
+
+## Dependencies
+
+Loaded via CDN — no build step needed:
+
+- [Three.js](https://threejs.org/) v0.170.0
+
+## License
+
+MIT — see [LICENSE](LICENSE).

index.html

@@ -9,7 +9,7 @@
     // Apply saved theme before first paint to avoid flash
     (function() {
       const t = localStorage.getItem('stlt-theme');
-      if (t === 'light') document.documentElement.setAttribute('data-theme', 'light');
+      if (t !== 'dark') document.documentElement.setAttribute('data-theme', 'light');
     })();
     // Apply saved language before first paint to avoid flash
     (function() {

js/i18n.js

@@ -102,8 +102,8 @@ export const TRANSLATIONS = {
     'progress.subdividing':          'Subdividing mesh\u2026',
     'progress.applyingDisplacement': 'Applying displacement to {n} triangles\u2026',
     'progress.displacingVertices':   'Displacing vertices\u2026',
-    'progress.decimatingTo':         'Decimating {from} \u2192 {to} triangles\u2026',
-    'progress.decimating':           'Decimating: {cur} \u2192 {to} triangles',
+    'progress.decimatingTo':         'Simplifying {from} \u2192 {to} triangles\u2026',
+    'progress.decimating':           'Simplifying: {cur} \u2192 {to} triangles',
     'progress.writingStl':           'Writing STL\u2026',
     'progress.done':                 'Done!',
     'progress.processing':           'Processing\u2026',
@@ -212,7 +212,7 @@ export const TRANSLATIONS = {
 
     // Export section
     'sections.export':               'Export \u24d8',
-    'tooltips.export':               'Kleinere Kantenl\u00e4nge = feineres Verschiebungsdetail. Die Ausgabe wird dann auf das Dreieckslimit dezimiert.',
+    'tooltips.export':               'Kleinere Kantenl\u00e4nge = mehr Texturdetails. Die Ausgabe wird dann auf das Dreieckslimit vereinfacht.',
     'labels.resolution':             'Aufl\u00f6sung',
     'tooltips.resolution':           'Kanten l\u00e4nger als dieser Wert werden beim Export unterteilt',
     'labels.outputTriangles':        'Max Dreiecke',
@@ -221,11 +221,11 @@ export const TRANSLATIONS = {
     'ui.exportStl':                  'STL exportieren',
 
     // Export progress stages
-    'progress.subdividing':          'Netz wird unterteilt\u2026',
-    'progress.applyingDisplacement': 'Verschiebung auf {n} Dreiecke anwenden\u2026',
-    'progress.displacingVertices':   'Vertices werden verschoben\u2026',
-    'progress.decimatingTo':         '{from} \u2192 {to} Dreiecke dezimieren\u2026',
-    'progress.decimating':           'Dezimieren: {cur} \u2192 {to} Dreiecke',
+    'progress.subdividing':          'Netz wird verfeinert\u2026',
+    'progress.applyingDisplacement': 'Textur auf {n} Dreiecke anwenden\u2026',
+    'progress.displacingVertices':   'Punkte werden verschoben\u2026',
+    'progress.decimatingTo':         '{from} \u2192 {to} Dreiecke vereinfachen\u2026',
+    'progress.decimating':           'Vereinfachen: {cur} \u2192 {to} Dreiecke',
     'progress.writingStl':           'STL schreiben\u2026',
     'progress.done':                 'Fertig!',
     'progress.processing':           'Verarbeitung\u2026',

js/presetTextures.js

@@ -14,18 +14,18 @@ function makeCanvas(size = SIZE) {
 // ── Image-based presets ───────────────────────────────────────────────────────
 
 const IMAGE_PRESETS = [
-  { name: 'Basket',   url: 'basket.jpg'   },
-  { name: 'Brick',    url: 'brick.jpg'    },
-  { name: 'Bubble',   url: 'bubble.jpg'   },
-  { name: 'Crystal',  url: 'crystal.jpg'  },
-  { name: 'Hexagon',  url: 'hexagon.jpg'  },
-  { name: 'Knitting', url: 'knitting.jpg' },
-  { name: 'Knurling', url: 'knurling.jpg' },
-  { name: 'Leather',  url: 'leather.jpg'  },
-  { name: 'Leather 2', url: 'leather2.jpg' },
-  { name: 'Weave',    url: 'weave.jpg'    },
-  { name: 'Wood',     url: 'wood.jpg'     },
-  { name: 'Noise',    url: 'noise.jpg'    },
+  { name: 'Basket',    url: 'textures/basket.jpg'   },
+  { name: 'Brick',     url: 'textures/brick.jpg'    },
+  { name: 'Bubble',    url: 'textures/bubble.jpg'   },
+  { name: 'Crystal',   url: 'textures/crystal.jpg'  },
+  { name: 'Hexagon',   url: 'textures/hexagon.jpg'  },
+  { name: 'Knitting',  url: 'textures/knitting.jpg' },
+  { name: 'Knurling',  url: 'textures/knurling.jpg' },
+  { name: 'Leather',   url: 'textures/leather.jpg'  },
+  { name: 'Leather 2', url: 'textures/leather2.jpg' },
+  { name: 'Weave',     url: 'textures/weave.jpg'    },
+  { name: 'Wood',      url: 'textures/wood.jpg'     },
+  { name: 'Noise',     url: 'textures/noise.jpg'    },
 ];
 
 function loadImagePreset({ name, url }) {