# ColorCalc – Interactive Colour Range Analyzer

ColorCalc is a desktop app for Windows/macOS/Linux that helps you identify and highlight colours in images. It is built with Python, Tkinter, and Pillow and is tuned for full‑HD screens. Instead of focusing on a single hue (like purple), you can target any colour range, tweak saturation/value thresholds, and export overlays in seconds.

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## Features

- 🎯 **Configurable hue detection** – adjust hue, saturation, and value windows or pick colours directly from the image/preset swatches.
- 🪟 **Responsive dual-preview UI** – original image on the left, processed overlay on the right, sized for 1080p.
- 🖱️ **Interactive masks** – draw exclusion rectangles to ignore specific regions when calculating results.
- 🌗 **Light & dark mode** – rounded toolbar buttons adapt to the current theme; toggle any time.
- 🟨 **Real‑time stats** – centre-aligned labels show match ratios with/without exclusions plus filenames and dimensions.
- 💾 **Overlay export** – save PNG overlays blended with the source image for reporting or further editing.
- ⚙️ **Config file defaults** – populate `config.toml` to ship different starting values across machines.
- 🎨 **Preset palette** – one-click access to common colours (red, cyan, grey, black, …).

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## Getting Started

### Requirements

- Python 3.11+ (includes the standard `tomllib`; for 3.10 install `tomli`)
- Tkinter (ships with most Python distributions; on Linux install `python3-tk`)
- Pillow (`pip install pillow`)

### Installation

```bash
git clone https://github.com/<your-org>/ColorCalc.git
cd ColorCalc
python3 -m venv .venv
source .venv/bin/activate  # Windows: .venv\Scripts\activate
pip install -r requirements.txt  # or pip install pillow
```

### Launch

```bash
python3 main.py
```

The window opens maximized; load an image, tweak sliders, and watch the overlay update in real time.

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## Usage Tips

- **Pick colours quickly:** use the 🎨 button to open a colour chooser or click directly inside the left preview (enable 🖱️ first).
- **Fine-tune defaults:** edit `config.toml` and set keys under `[defaults]`. Restart the app to apply changes.
- **Reset & compare:** `🔄 Slider zurücksetzen` reverts to defaults and clears the status message.
- **Exclude areas:** right-drag on the original preview to mark rectangles; use `↩️` to undo or `🧹` to clear all.
- **Copy stats:** right-click the filename or ratio labels to copy.
- **Export overlay:** `💾` saves a PNG with your overlay merged onto the source image.
- **Theme switch:** `🌓` toggles between light/dark; button palettes update instantly.

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## Project Structure

```
ColorCalc/
├── app/
│   ├── app.py                # ColorCalcApp composition root
│   ├── __init__.py           # Package exports
│   ├── gui/
│   │   ├── color_picker.py   # Colour selection & presets
│   │   ├── exclusions.py     # Exclusion rectangle handlers
│   │   ├── theme.py          # Theme detection & style updates
│   │   └── ui.py             # Tkinter layout and custom widgets
│   └── logic/
│       ├── constants.py      # Config defaults & preview sizing
│       ├── image_processing.py # Loading, overlay creation, stats
│       └── reset.py          # Slider reset mixin
├── config.toml               # Default HSV/alpha overrides
├── images/                   # Optional sample inputs
└── main.py                   # CLI entry point (`python3 main.py`)
```

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## Configuration (`config.toml`)

```toml
[defaults]
hue_min = 250.0  # 0..360°
hue_max = 310.0
sat_min = 15.0   # percentage 0..100
val_min = 15.0
val_max = 100.0
alpha = 120      # overlay opacity 0..255
```

All values are optional; omit them to fall back to built-in defaults. Hue min/max support wrap-around (e.g. 350 to 20).

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## Development Workflow

- Format: project sticks to standard Python style; no formatter enforced.
- Testing: primary quick check is compilation via `python3 -m compileall app main.py`.
- Platform quirks: some theme detection uses Windows registry; errors are swallowed when unavailable.

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## Contributing

1. Fork + clone.
2. Create a feature branch.
3. Make changes and run `python3 -m compileall app main.py`.
4. Submit a PR with a clear description and screenshots if UI changes are visible.

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## License

MIT License © 2024 ColorCalc contributors. See `LICENSE` (add one if missing) for details.