`joy_skyboxrotate.py`

### What it is for
A drag-and-drop GUI for rotating a 6-face skybox set in 90-degree increments.

This is meant for Kingpin/Quake-style cubemap skyboxes named with the usual face suffixes.

### Dependencies
```bash
pip install pillow tkinterdnd2
```

### Expected filenames
It expects exactly six `.tga` files whose names end in:

- `up`
- `dn`
- `ft`
- `bk`
- `lf`
- `rt`

Example:
- `myskyup.tga`
- `myskydn.tga`
- `myskyft.tga`
- `myskybk.tga`
- `myskylf.tga`
- `myskyrt.tga`

### Usage
```bash
python joy_skyboxrotate.py
```

### How to use
1. Launch the program.
2. Drag the 6 TGA skybox faces into the window.
3. Click one of:
   - **Turn 90**
   - **Turn 180**
   - **Turn 270**

### What the rotation does
For a 90-degree turn:
- `up` is physically rotated 90° clockwise
- `dn` is physically rotated 90° counter-clockwise
- side faces are renamed:
  - `ft -> rt`
  - `lf -> ft`
  - `bk -> lf`
  - `rt -> bk`

180 and 270 just apply that step multiple times.

### Arguments
None. This is GUI-only.

### Output
Writes the rotated faces back out as:
- 24-bit RGB
- compressed TGA

with the same prefix and the updated suffix names.