Variable AttachmentDescription.ops
the operations to be performed on the attachment color and depth attachments may only need to define the ops member depth-stencil attachments must define both ops (for depth) and stencilOps members.
struct AttachmentDescription
{
// ...
AttachmentOps ops
= AttachmentOps(cast(LoadOp)2, cast(StoreOp)1);
// ...
}