`point_size`

In `gl_context.rs`, the method to change the point size is commented out, without any comment as to why.

```
fn point_size(&self, _size: f32) {
// unsafe { self.context.point_size(_size) }
}
```

Is there a reason changing point size is commented out?

We uncommented it and it works fine on some platforms but not all -- on the Apple M1 machine, for instance, it fails to change the point size.

Start in gl_context.rs at the commented-out point_size method and inspect how point-size changes are handled across the supported platforms. Reproduce the behavior on a non-Apple platform and an Apple M1 machine, then determine whether the method should be enabled, adapted, or documented as unsupported.

Written by the indexing model from the issue text.