# NanoGUI Experiments

![NanoGUI Knobs example app](nanogui_knobs.png)

## Building

### Python

Set up virtual environment providing nanogui Python bindings:

```con
python3 -m venv venv
source venv/bin/activate
(venv) pip install -r requirenments.txt
```

Run helloworld examples:

```con
(venv) python3 nanogui_helloworld.py
(venv) python3 nanogui_custowidget.py
```

### C++

Configure build with *CMake*:

```con
cmake -B build -S .
```

(This will checkout the NanoGUI library from GitHub into the build directory.
You can use `-DNANOGUI_REPO=<repo path or URL>` to change from where Git will
retrieve the repository.)

Build the examples:

```con
cmake --build build
```

Run hellworld example:

```con
./build/nanogui_helloworld
```


## Knobs Example


### Python

```con
(venv) python3 nanogui_knobs.py
```


### C++

```con
./build/nanogui_knobs
```


### Key and Mouse Bindings

|                                           |                      |                         |
| ----------------------------------------- | -------------------- |------------------------ |
| Mouse click-and-drag knob                 | coarse in-/decrement | +/- one 100th / pixel   |
| Shift + mouse click-and-drag knob         | fine in-/decrement   | +/- 0.1 / pixel         |
| Mouse wheel scroll over knob              | coarse in-/decrement | one 100th / click * 2.0 |
| Shift + mouse wheel scroll over knob      | fine in-/decrement   | +/- 0.1 / click         |
| Ctrl + left click on knob                 | set to default value |                         |
| Up/down key while mouse over knob         | coarse in-/decrement | +/- one 100th           |
| Shift + up/down key while mouse over knob | fine in-/decrement   | +/- 0.1                 |
| Page up/down key while mouse over knob    | big in-/decrement    | +/- one 10th            |
| Mouse click on value entry up/down arrow  | fine in-/decrement   | +/- 0.1                 |
| Mouse wheel scroll over value entry       | fine in-/decrement   | +/- 0.1 / click         |
| Return/Enter while editing value entry    | accept & set value   |                         |
| Escape key                                | quit                 |                         |


### Notes

* No support for scaling or re-layouting on window resize yet.
* Only the knob value gauge color can currently be specified on instantation,
  the knob gradient and outline colors are currently hard-coded.