What is Gami UI Editor?

Gami UI Editor is a free, browser-based tool that automates the Unity UI workflow. It batch-converts 9-slice sprite images into ready-to-import Unity prefab ZIPs, parses PSD files into auto-cropped prefabs, and optimizes images to WebP. All processing runs locally in the browser using WebAssembly — no image data is uploaded to any server. Free, no account required, processes up to 30 files per batch.

How does the auto 9-slice detection work?

Gami UI Editor scans each sprite's pixel data on the client to find the largest stretchable interior region. It detects edges by analyzing alpha and color uniformity along each border, then sets the top, right, bottom, and left 9-slice values to preserve corners and edges during scaling. Detected borders can be reviewed and adjusted via drag-guides or numeric inputs before export.

Does Gami UI Editor process images locally or on a remote server?

Gami UI Editor processes all images locally on the user's device. The tool uses a WebAssembly (WASM) build of Google's libwebp library plus client-side canvas pixel scanning for 9-slice detection. No image data is transmitted to any server at any point in the workflow. This is verifiable by inspecting Network DevTools — zero outbound image requests are recorded during any conversion or batch operation.

Is Gami UI Editor free to use, and does it require registration?

Gami UI Editor is free to use with no registration required for the WebP optimizer. Unity prefab export uses a small daily credit allowance (refilled every 24 hours) to keep the service sustainable; signed-in users get more credits per day. Every core feature — batch conversion of up to 30 files, quality control, bulk resize, in-browser ZIP export, and 9-slice auto-detection — is available on first visit.

How does WebP format affect page load speed and SEO rankings?

WebP files are 25-34% smaller than JPEG and 60-80% smaller than PNG at equivalent perceptual quality. Smaller image files reduce the payload of the Largest Contentful Paint (LCP) element — a Core Web Vitals signal Google uses as a direct ranking factor in organic search. Converting images to WebP resolves the "Serve images in next-generation formats" warning in Google Lighthouse and PageSpeed Insights audits.

How efficient is Gami UI Editor for batch-processing large image sets?

Gami UI Editor encodes up to 30 images simultaneously using parallel Web Workers, so total batch processing time does not scale linearly with file count. All converted files are packaged into a single ZIP archive assembled entirely in-browser without server involvement. Users can run unlimited batches per session, with no queue and no wait time between jobs.

Which operating systems and browsers does Gami UI Editor support?

Gami UI Editor runs on any operating system — Windows, macOS, Linux, iOS, and Android — in any browser that supports WebAssembly and the File API: Chrome 57+, Firefox 52+, Safari 11+, and Edge 16+. No installation, plugin, or browser extension is required. The tool also deploys as an offline-capable Progressive Web App installable on desktop and mobile home screens.

How do I import the exported prefab ZIP into Unity?

Install the GamiPrefabImporter Editor utility (free, MIT-licensed, available from the Unity importer page) into your Unity project under Assets/GamiPrefabImport/Editor. Drag the exported ZIP into your project window. The importer reads each layout.json, creates Unity sprites with the correct 9-slice borders and pixels-per-unit, and assembles them into ready-to-use UI prefabs — including Button components if marked during export.

Can Gami UI Editor convert images without an internet connection?

Yes. Gami UI Editor functions fully offline after the first page load. A Service Worker (v6) caches all application assets including the WebAssembly encoder on first visit. Users can install it as a Progressive Web App and run batch WebP conversions on an air-gapped device with no network access required. (Unity prefab export is the one feature that needs network access, since it calls a credits API.)

Gami UI Editor — Free Unity UI Prefab Generator & Image Optimizer

Gami UI Editor is a free, browser-based tool that automates the Unity UI workflow. Batch convert 9-slice sprite images into ready-to-import Unity prefab ZIPs, parse PSD files into auto-cropped 9-sliced prefabs, and optimize PNG and JPEG images to WebP — all entirely in your browser. No uploads, no sign-in, no server processing.

Unity UI workflow automation

Drop sprite images and Gami UI Editor auto-detects 9-slice borders by scanning pixel edges, builds a Unity-ready layout.json, and packages everything into a ZIP that the GamiPrefabImporter Editor utility imports as fully-configured prefabs with correct pixels-per-unit and optional Button components attached.

Batch image optimization

Beyond Unity prefab generation, Gami UI Editor functions as a fast batch image optimizer. Convert PNG and JPEG to WebP using Google's libwebp compiled to WebAssembly, processing up to 30 files in parallel via Web Workers. Smaller images mean faster Largest Contentful Paint (LCP) — a direct Core Web Vitals ranking signal.

Privacy by architecture

All image processing runs locally inside the browser's sandboxed memory. No upload API exists in the data pipeline. This is verifiable by inspecting Network DevTools — zero outbound image requests during any conversion or batch operation. GDPR and PDPA compliant by design. Works fully offline after first load via Service Worker v6 and PWA installation.

Key features

Batch 9-slice to Unity prefab generator — drop sprites, export ready-to-import ZIP
PSD → Unity prefab pipeline — auto-crops layers, detects borders, builds layout.json
Nav bar / button generator — design Unity navigation prefabs in the browser
Client-side WebP conversion using libwebp via WebAssembly
Batch processing of up to 30 images in parallel via Web Workers
PNG to WebP with alpha transparency preserved
JPEG to WebP with quality presets (High 92%, Balanced 80%, Smallest 60%)
Bulk image resizing with aspect-ratio lock
In-browser ZIP batch download — assembled without server involvement
Smart Auto Fix: brightness, contrast, saturation correction
Offline support via Service Worker v6 and PWA installation
Free, no account required for image optimization

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