Add example

README.md

@@ -82,6 +82,23 @@ Builders implement `Deref` targeting their corresponding Vulkan struct, so refer
 to Vulkan functions. This is encouraged as doing so allows Rust to check the lifetimes of captured objects are valid,
 whereas calling `build` discards lifetime information, making inadvertent use-after-free errors more likely.
 
+### Pointer chains
+
+```Rust
+let mut variable_pointers = vk::PhysicalDeviceVariablePointerFeatures::builder();
+let mut corner =
+    vk::PhysicalDeviceCornerSampledImageFeaturesNV::builder();
+;
+let mut device_create_info = vk::DeviceCreateInfo::builder()
+    .push_next(&mut corner)
+    .push_next(&mut variable_pointers);
+```
+
+Pointer chains in builders differ from raw Vulkan. Instead of chaining every struct manually, you instead use `.push_next` on the struct that you are going to pass into the function. Those structs then get *pepended* into the chain.
+
+`push_next` is also type checked, you can only add valid structs to the chain. Both the structs and the builders can be passed into `push_next`. Only builders for structs that can be passed into functions will implement a `push_next`.
+
+
 ### Flags and constants as associated constants
 
 ```Rust