I am using **Visual Studio for Mac** and trying to revive a project that written in XamarinStudio about 2 years ago.
Code written in C#.

When I try to build the project, there is a lot of error that saying:

```
namespace Drawing does not exist in the namespace System(are you missing an assembly reference?).

```

Past in the time this code compiled.

What package should I install to get System.Drawing namespace or what can substitute System.Drawing namespace?

I need PointF structure from that namespace.