SmaPlot An Open Source Web-Based Alternative to Sma4Win

Finding an alternative to Sma4Win often presents a unique challenge for researchers and science students. While modern scientific plotting software like OriginLab, Igor Pro, or Python libraries is exceptionally capable, these tools do not natively open .SMP project files, have steep learning curves, and often require expensive licenses or intricate setup procedures.

In most laboratory settings, what researchers actually need is the classic, lightweight workflow of Sma4Win, specifically the ability to quickly plot X and Y data pairs, configure four independent axes, and perform least-squares curve fits without being tied to legacy Windows operating systems.

To address this need, I developed SmaPlot. It is a free open source web-based alternative designed to bring the familiar Sma4Win workflow directly to modern browsers across Windows, macOS, Linux, and tablets, complete with native support for opening and saving .SMP project files.

Understanding Sma4Win and Its Modern Limitations

Sma4Win (Sma4 for Windows) was originally created by Suzuki Tomoo and Makimura Tetsuya. Its native .SMP project format along with plain text data formats became lab staples because the software was lightweight, fast, and straightforward for plotting X-Y data pairs. Alongside direct printing and saving project files, a major strength of Sma4Win on Windows was its ability to copy graphs to the clipboard or export them as vector .EMF and .WMF files, allowing sharp inserts into Microsoft Word and PowerPoint documents.

Despite its reliability, using Sma4Win today presents several practical drawbacks.

• It only runs natively on Windows and requires compatibility layers like Wine on macOS or Linux.
• It lacks modern canvas navigation features such as pinch-to-zoom and smooth trackpad gestures.
• There is no straightforward way to view or edit projects on tablets or non-Windows machines without complex setup.

What Is SmaPlot

SmaPlot is designed as a web app that replicates the look and workflow of Sma4Win without requiring any installation. It natively supports the .SMP format, allowing you to open existing Sma4Win project files, adjust data and graphs, and export them back to .SMP while maintaining full compatibility with the original software.

In addition to .SMP project files, SmaPlot currently imports plain text dataset files in .TXT format. All data processing runs strictly on the client side in your browser, ensuring that your research datasets remain completely private and local to your device.

The tool is completely free and open source under the MIT license. You can use it across Windows, macOS, Linux, and tablets via any modern browser, or install it as a Progressive Web App (PWA) for offline use.

Core Features in SmaPlot

SmaPlot combines classic plotting conventions with interactive SVG canvas capabilities. Key features include the following.

• A multi-plot workspace with support for dragging, resizing, group selections, and snap to grid for clean chart layouts.
• An independent four-axis system for X, Y, Top, and Right axes, complete with custom range settings, subdivisions, and font options.
• Dataset management and mathematical transforms for X and Y, including interactive curve adjustments directly on the canvas.
• Tools for text labels, lines, arrows, and an insert symbol dialog for Greek and mathematical characters.
• A Data Manager to import multiple data files simultaneously with automatic naming and mathematical expressions.
• Flexible canvas navigation using keyboard shortcuts, mouse scroll, middle-click drag, or trackpad touch gestures.
• A Read Value dialog with Find Highest and Find Lowest buttons to easily locate peaks in spectrum or diffraction data.
• Native .SMP project saves, vector .SVG export, raster .PNG and .JPG image exports, and a quick copy-to-clipboard feature for pasting charts directly into documents or presentations.

Comparison Between Sma4Win and SmaPlot

The following table outlines the technical and functional differences between both tools.

Feature and Aspect	Classic Sma4Win	SmaPlot Web
Platform	Windows desktop	Web browser (Windows, macOS, Linux, tablets)
Installation	Requires system installation	No installation required (optional PWA)
Project Format	.SMP	.SMP (two-way compatible)
Data Format	.SMA, .TXT	.SMP, .TXT (currently supported)
Canvas Navigation	Coordinate dialog entries	Interactive pan and zoom, trackpad gestures, snap to grid
Curve Adjustments	Manual numerical inputs in YTrans	Direct dragging on the canvas curve
Special Symbols	Manual symbol fonts	Insert Symbol picker with instant search
Visual Export	Printer output, file save, copy to clipboard, or .EMF and .WMF export	Direct copy to clipboard, .SVG, .PNG, and .JPG export

How to Use and Install SmaPlot

You can run SmaPlot immediately in any browser without downloading an installer package.

1. Open the SmaPlot page on this site.
2. Click the Launch App button to open the main workspace.
3. Drag and drop your .SMP or .TXT files directly onto the canvas, or use the File menu to load data.

If you want to use SmaPlot like a desktop application without opening browser tabs manually, you can install it as a Progressive Web App (PWA).

• Click the Install option available directly in the SmaPlot menu bar to trigger the PWA installation prompt.
• Alternatively, you can click the browser’s native install icon in the address bar or select Add to Home Screen on tablet devices.

Once installed, SmaPlot opens in its own standalone window and can be launched directly from your desktop app list or tablet home screen.

Frequently Asked Questions (FAQ)

• Which file formats are currently supported in SmaPlot?

  SmaPlot currently supports two primary formats, native .SMP project files (the original Sma4Win project format) and plain text .TXT data files. Files in .SMP format can be loaded and saved with full two-way compatibility for classic Sma4Win, while .TXT files are used to import raw column-based data.

• Are my research datasets uploaded to any server?

  No. SmaPlot is built local-first. All file parsing, SVG rendering, mathematical transforms, and exports run entirely in your local browser memory. No data is ever transmitted or stored on an external server.

• Can .SMP files saved in SmaPlot be reopened in the original Sma4Win?

  Yes. The .SMP save parser in SmaPlot is built for two-way compatibility. Plot coordinates, four-axis configurations, curve series, annotations, and special symbols open cleanly in classic Sma4Win without breaking the file structure.

• Can I use SmaPlot without an active internet connection?

  Yes. Once the web app has been opened and installed as a PWA on your device, all necessary application assets are cached locally, allowing you to launch and use SmaPlot completely offline.

• What is the current development status and how can I provide feedback?

  SmaPlot is under active development as additional specialized features are gradually implemented. If you encounter bugs, have feature requests, or want to contribute to the codebase, the SmaPlot GitHub repository is open. Feedback from active researchers is always welcome.