feat: update README for improved clarity and add .gitignore for assets

.gitignore

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+assets/

README.md

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 **Live demo:** https://cnckitchen.github.io/stlTexturizer/
 
-A browser-based tool for applying surface displacement textures to STL files — no installation required.
+A browser-based tool for applying surface displacement textures to 3D meshes — no installation required.
 
-Load any `.stl` file, pick a texture, tune the parameters, and export a new displaced STL ready for slicing.
+Load an STL, OBJ, or 3MF file, pick a texture, tune the parameters, and export a new displaced STL ready for slicing.
 
 ## Features
 
-- **Texture presets** — 17 built-in seamless textures (basket, brick, bubble, carbon fiber, crystal, grip surface, hexagons, knitting, knurling, leather, noise, voronoi, weave variations, wood, and more)
+### Textures
+- **18 built-in seamless textures** — basket, brick, bubble, carbon fiber, crystal, dots, grip surface, hexagons, knitting, knurling, leather, leather 2, noise, voronoi, weave (×3 variants), wood
 - **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
+### Projection Modes
-- **Displacement amplitude** — fine-tune depth from subtle grain to deep relief
+- **Triplanar** (default) — blends three planar projections based on surface normals; best for complex shapes
-- **Surface mask** — skip horizontal top/bottom faces to keep flat surfaces clean
+- **Cubic (Box)** — projects from 6 box faces with edge-seam blending and smart axis dominance
-- **Surface exclusions / inclusions** — paint individual faces with a brush or bucket-fill to exclude or exclusively include them from displacement
+- **Cylindrical** — wraps texture around a cylindrical axis with configurable cap angle
-- **Live preview** — real-time textured 3D preview with orbit/pan/zoom controls
+- **Spherical** — maps texture spherically around the object
-- **Mesh subdivision** — auto-subdivides coarse geometry before displacement for smoother results
+- **Planar XY / XZ / YZ** — flat axis-aligned projections
-- **Export** — downloads a new binary STL with displacement baked in
+
-- **Light / Dark theme** — persisted per browser
+### UV & Transform Controls
-- **Multilingual** — English and German UI
+- **Scale U/V** — independent or locked scaling (0.05–10×, logarithmic)
+- **Offset U/V** — position the texture on each axis
+- **Rotation** — rotate texture before projection
+- **Seam Blend Strength** — softens hard edges where Cubic/Cylindrical projection faces meet
+- **Seam Band Width** — controls blending zone width at seam edges
+- **Cap Angle** (Cylindrical) — threshold for switching to top/bottom cap projection
+
+### Displacement
+- **Amplitude** — scales displacement depth from 0 % to 100 %
+- **Symmetric displacement** — 50 % grey stays neutral, white pushes out, black pushes in (preserves volume)
+- **3D displacement preview** — real-time GPU-accelerated preview toggle showing actual vertex displacement
+- **Amplitude overlap warning** — alerts when depth exceeds 10 % of the smallest model dimension
+
+### Surface Masking
+- **Angle masking** — suppress texture on near-horizontal top and/or bottom faces (0°–90° threshold each)
+- **Face exclusion / inclusion painting** — paint individual faces to exclude (orange) or exclusively include (green) them
+  - Brush tool — single-triangle click or adjustable-radius circle brush
+  - Bucket fill — flood-fills adjacent faces up to a configurable dihedral-angle threshold
+  - Erase — hold Shift to undo painted faces
+  - Clear all — reset masking
+
+### Mesh Processing
+- **Adaptive subdivision** — subdivides edges until they are ≤ a target length; respects sharp creases (>30° dihedral)
+- **QEM decimation** — simplifies the result to a target triangle count using Quadric Error Metrics with boundary protection, link-condition checks, normal-flip rejection, and crease preservation
+- **Safety cap** — hard limit of 10 M triangles during subdivision to prevent out-of-memory
+
+### 3D Viewer
+- **Orbit / pan / zoom** controls
+- **Wireframe toggle** — visualise mesh topology
+- **Mesh info** — live triangle count, file size, bounding-box dimensions
+- **Grid & axes indicator** — X = red, Y = green, Z = blue
+- **Place on Face** — click a face to orient it downward onto the print bed
+
+### File Support
+- **.STL** — binary and ASCII
+- **.OBJ** — via Three.js OBJLoader
+- **.3MF** — ZIP-based format (via fflate decompression)
+
+### Export
+- Downloads a **binary STL** with displacement baked in
+- Progress reporting through subdivision → displacement → decimation → writing stages
+- Configurable edge-length threshold and output triangle limit
+
+### Other
+- **Light / Dark theme** — respects OS preference, persisted per browser
+- **Multilingual** — English and German UI with auto-detection
 
 ## 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…**.
+2. Drop a model onto the viewport or click **Load STL…** (supports STL, OBJ, 3MF).
 3. Select a texture preset from the sidebar (or upload a custom image).
-4. Adjust projection mode, UV scale, offset, rotation, and amplitude.
+4. Choose a projection mode and adjust UV scale, offset, rotation, and amplitude.
-5. Optionally mask or exclude surfaces with the brush/fill tools.
+5. Optionally mask or exclude surfaces with the angle sliders or paint 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.
@@ -35,29 +81,30 @@ Load any `.stl` file, pick a texture, tune the parameters, and export a new disp
 ## Project Structure
 
 ```
-index.html          # Main entry point
+index.html            # Main entry point
-style.css           # Styles (light/dark theme)
+style.css             # Styles (light / dark theme)
-textures/           # Built-in JPG displacement map images
+textures/             # Built-in JPG displacement map images (18 textures)
 js/
-  main.js           # App bootstrap & UI wiring
+  main.js             # App bootstrap & UI wiring
-  viewer.js         # Three.js scene / camera / controls
+  viewer.js           # Three.js scene / camera / controls
-  stlLoader.js      # Binary & ASCII STL parser
+  stlLoader.js        # Binary & ASCII STL parser
-  presetTextures.js # Built-in texture presets + custom upload
+  presetTextures.js   # Built-in texture presets + custom upload
-  previewMaterial.js# Three.js material for live preview
+  previewMaterial.js  # Three.js material for live & displacement preview
-  mapping.js        # UV projection logic
+  mapping.js          # UV projection logic (7 modes)
-  displacement.js   # Vertex displacement baking
+  displacement.js     # Vertex displacement baking
-  subdivision.js    # Mesh subdivision
+  subdivision.js      # Adaptive mesh subdivision
-  decimation.js     # QEM mesh decimation
+  decimation.js       # QEM mesh decimation
-  exclusion.js      # Face exclusion / inclusion painting
+  exclusion.js        # Face exclusion / inclusion painting
-  exporter.js       # Binary STL export
+  exporter.js         # Binary STL export
-  i18n.js           # Translations (EN / DE)
+  i18n.js             # Translations (EN / DE)
 ```
 
 ## Dependencies
 
 Loaded via CDN — no build step needed:
 
-- [Three.js](https://threejs.org/) v0.170.0
+- [Three.js](https://threejs.org/) v0.170.0 (including STLLoader, OBJLoader, OrbitControls, etc.)
+- [fflate](https://github.com/101arrowz/fflate) v0.8.2 — ZIP decompression for .3mf files
 
 ## License