StorageImage
    General-purpose image in device memory.
AttachmentImage
    ImageAccess whose purpose is to be used as a framebuffer attachment




Hello!

Any of you guys use the Vulkano library? There is this PersistentDescriptorSetBuilder struct
which uses this fun chaining dynamic

```
PersistentDescriptorSet::start(layout, 0)
            .add_sampled_image(sampled_image1).unwrap()
            .add_sampled_image(sampled_image2).unwrap()
            .add_sampled_image(sampled_image3).unwrap()
            .build().unwrap();
```

But it modifies the return values template values so I can't store it between loops

```
let mut set_builder = PersistentDescriptorSet::start(layout, 0);
for image in images {
    set_builder = set_builder.add_sampled_image(image);
}
let descriptor_set = set_builder.build().unwrap();
```

The gist of the error that I get is something like:

```
expected:
PersistentDescriptorSetBuilder<Arc<GraphicsPipelineAbstract>, ()>
got:
PersistentDescriptorSetBuilder<Arc<GraphicsPipelineAbstract>, ((), PersistentDescriptorSetImg<Arc<ImmutableImage<Format>>>)>
```

So it's adding tuples of tuples of tuples of tuples of tuples each time I chain a
.add_sampled_image() call. I really really want to be able to do this dynamically in
a loop; I've tried this neat iter().fold() thinking that if I didn't explicitly
overwrite the previous returned value, rust would figure it out. It didn't

```
let descriptor_set = images.iter().fold(
    PersistentDescriptorSet::start(layout, 0)
    ,|a, &b| a.add_image(b))
    .unwrap()).build().unwrap();
```

How do I do this dynamically?