Horizontal DAG graph

I use Diagon for comments in my source code, so the vertical orientation is inconvenient.
Is it possible to have horizontal orientation?
```
horizontal:
┌─┐┌─┐
│a->b|
└─┘└─┘

vertical:
┌─┐
│a│
└┬┘
┌▽┐
│b│
└─┘

```