# v0.7.1 — Large STL files open in a blink

## ✨ New features

**Large STL files open in a blink**
* Opening big STL meshes (tens of MB, millions of triangles) is now near-instant instead of a multi-minute wait. A 75 MB / 1.5-million-triangle STL that used to take ages now shows in **under a second**.
* STL is now parsed directly instead of going through the CAD kernel's importer, which used to build a full B-rep face per triangle (100k triangles: **~41 s → ~11 ms**). Both binary and ASCII STL are detected and read automatically.

**Customizable menu bar & quick toolbar**
* A full menu bar groups every feature into categorized dropdowns, and a quick toolbar lets you tick just the buttons you use most — your selection is remembered between sessions.

**About dialog with a changelog**
* Help → About now shows a per-version, plain-language changelog so you can see what each release brought.

## 🐛 Bug fixes

**STL geometry no longer leaks into STEP export**
* STL is pure mesh (no B-rep), so STL parts are now correctly excluded from STEP export — earlier versions wrongly mixed STL shells into the exported STEP. Rigid transforms and measurement on STL parts are unaffected.

## 📦 Downloads

| Build | Needs .NET Runtime? | Notes |
|---|---|---|
| **STPViewer_v0.7.1** (Standard) | ✅ Requires .NET 8 Desktop Runtime | Smaller download |
| **STPViewer_v0.7.1_portable** (Portable) | ❌ Runtime included | Unzip and run anywhere, no admin |

Run `STPViewer v0.7.1.exe`.

## 🔗 Links

* [Architecture](https://github.com/ETWen/STPViewer/blob/main/ARCHITECTURE.md)
* [README](https://github.com/ETWen/STPViewer/blob/main/README.md)

**Full changelog:** [v0.6.0...v0.7.1](https://github.com/ETWen/STPViewer/compare/v0.6.0...v0.7.1)