PolyEcho

A focused, browser-based low-poly 3D modeling, UV pixel painting, and skeletal animation suite built with Vue 3, TypeScript, and Three.js.

Designed from the ground up for indie game developers, retro game creators (PS1/DS/N64 styles), and technical artists who want a fast, no-nonsense workflow without the overhead of massive DCC packages.

Core Workflow

PolyEcho combines four integrated workspaces:

[ MODEL ] ➔ [ UV / PAINT ] ➔ [ RIG ] ➔ [ ANIMATE ] ➔ [ GLB / OBJ EXPORT ]

1. Model: Box modeling, quad & n-gon topology editing, Blender-style modal CAD gizmos (G, R, S, E, I, Ctrl+B, K, Ctrl+R, Shift+A).
2. UV / Paint: Interactive pixel canvas, Bayer 8x8 dithering brushes, retro color palette indexing (PSX, Pico-8, GameBoy, NES), and 3D vertex painting.
3. Rig: Visual bone extrusion, hierarchical joint parenting, symmetrize (L/R), and 1-click rigid limb part assignment or 4-influence smooth skinning.
4. Animate: Multi-action clip library (Idle, Walk, Attack, etc.), dope-sheet timeline, automatic/manual keyframing, pose mirroring, timeline event markers, and GLB Animator-inspired real-time clip blending.

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Features

1. Essential Low-Poly Modeling

• Selection Modes: Object (4), Origin/Pivot (5), Vertex (1), Edge (2), Face (3).
• Modal Operators: Move (G), Rotate (R), Scale (S), Extrude (E), Inset (I), Bevel (Ctrl+B), Knife Topology (K), Loop Cut & Slide (Ctrl+R).
• Topology Operations:
  • Merge at Center (M), First, Last, and Distance (Weld).
  • Fill Face from Boundary (F) and Connect Vertices (J).
  • Dissolve Edges and Vertices.
  • Divide / Subdivide (Quads into 4 quads, edges with midpoint interpolation).
  • Flip Edge Diagonal (Rotate triangle hypotenuse).
  • Separate Selection (P) & Join Meshes (Ctrl+J).
  • Flip Face Normals & Recalculate Outside Normals.
  • Safe Mesh Cleanup (removes zero-length edges, orphan vertices, degenerate polygons).
• Interactive CAD Placement (Shift+A): Draw primitives (Box, Plane, Cylinder, Cone, Sphere, Icosphere) directly on grids or surface geometry with snap alignment.

2. Retro Texture & UV Painting

• 2D Pixel Canvas with layers, flood fill, color picker, Bayer matrix dithering, and eraser.
• Automatic planar, box, and cylindrical UV unwrap solvers.
• Real-time 3D Viewport pixel painting and vertex color painting.
• Authentic retro color quantization presets.

3. Rigging & Part Parenting

• Rigid Part Animation (Default): Assign distinct mesh objects to bones with 100% influence for robots, low-poly characters, and props.
• Smooth Skinned Mesh: Distance-based automatic vertex weight assignment normalized up to 4 bone influences.
• Visual joint manipulators, bone extrusion (E), bone subdivision, and X-axis symmetrization.

4. Game Animation System

• Multiple Named Animation Clips: Store as many clips as your game requires (Idle, Walk, Run, Attack_01, Death) in a single model file.
• Timeline & Dope Sheet: Compact expandable bone/channel tracks, frame transport controls, adjustable FPS (8, 12, 15, 24, 30, 60), and duration scaling.
• Keyframe Tools: Position, Rotation (quaternion slerp), Scale channels, Auto Key toggle, Copy/Paste Pose, Paste Mirrored Pose (for walking cycles).
• Interpolation: Smooth (CUBICSPLINE), Linear (LINEAR), and Step (STEP for snappy retro stop-motion animation).
• Timeline Markers / Game Events: Place named event flags (e.g. footstep_l, hit_frame, land) exported directly in GLB animation metadata.
• Clip Blend Preview: Live spherical blend testing between any two animation clips with percentage sliders.

5. Import & Export Pipeline

• GLTF / GLB (.glb): Multi-animation skeletal export with bone hierarchies, rigid limb assignments, smooth skins, materials, and marker event metadata in extras.
• Wavefront OBJ / MTL (.obj): Compatible with Blender, Godot, Unity, Unreal Engine, and custom game engines.
• Project Files (.psxproj): Self-contained JSON project format with full undo/redo state history.

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Keyboard Shortcuts

Shortcut	Action
1 / 2 / 3	Vertex / Edge / Face Select Mode
4 / 5	Object / Origin (Pivot) Mode
Tab	Toggle Object / Edit Mode
G / R / S	Move / Rotate / Scale
E / I	Extrude / Inset Faces
Ctrl + B	Bevel / Chamfer
Ctrl + R	Loop Cut & Slide
K	Knife Topology Tool
F	Fill Face / Bridge Loop
J	Connect 2 Selected Vertices
M	Merge Vertices Menu
P	Separate Selected Geometry to New Object
Ctrl + J	Join Selected Mesh Objects
Shift + D	Duplicate Selection
Delete / X	Delete Selection
Shift + A	Add Primitive Menu (at cursor)
Space	Play / Pause Timeline Animation
Ctrl + Z / Ctrl + Y	Undo / Redo
Ctrl + S / Ctrl + O	Save / Open Project
Ctrl + E	Quick Export GLB

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Getting Started

Prerequisites

• Node.js 18+
• npm / pnpm / yarn

Installation & Run

# Clone the repository
git clone https://github.com/CharmingBlaze/polyecho.git
cd polyecho

# Install dependencies
npm install

# Start local development server
npm run dev

# Build for production
npm run build

Open http://localhost:5173 in your browser.

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Tech Stack

• Framework: Vue 3 (Composition API, <script setup>, TypeScript)
• 3D Engine: Three.js
• State Management: Pinia
• Styling: Tailwind CSS
• Icons: Lucide Vue & Custom Blender DCC SVGs
• Build Tool: Vite

License

MIT License. Free to use for personal, indie, and commercial game development.