FastAnvil

https://docs.rs/fastanvil/0.32.0/fastanvil/
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FastAnvil is a Rust crate for handling Minecraft's Anvil region format, enabling reading, writing,...
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### Result::is_ok_and Method

Source: https://docs.rs/fastanvil/0.32.0/fastanvil/type.Result.html

Example of checking if a Result is Ok and matches a predicate.

```rust
let x: Result<u32, &str> = Ok(2);
assert_eq!(x.is_ok_and(|x| x > 1), true);

let x: Result<u32, &str> = Ok(0);
assert_eq!(x.is_ok_and(|x| x > 1), false);

let x: Result<u32, &str> = Err("hey");
assert_eq!(x.is_ok_and(|x| x > 1), false);

let x: Result<String, &str> = Ok("ownership".to_string());
assert_eq!(x.as_ref().is_ok_and(|x| x.len() > 1), true);
println!("still alive {:?}", x);
```

--------------------------------

### Result::is_ok Method

Source: https://docs.rs/fastanvil/0.32.0/fastanvil/type.Result.html

Example of checking if a Result is Ok.

```rust
let x: Result<i32, &str> = Ok(-3);
assert_eq!(x.is_ok(), true);

let x: Result<i32, &str> = Err("Some error message");
assert_eq!(x.is_ok(), false);
```

--------------------------------

### Safely get Ok value (nightly)

Source: https://docs.rs/fastanvil/0.32.0/fastanvil/tex/type.Result.html

The `into_ok()` method returns the contained `Ok` value and is guaranteed not to panic. This is a nightly-only experimental API.

```rust
fn only_good_news() -> Result<String, !> {
    Ok("this is fine".into())
}

let s: String = only_good_news().into_ok();
println!("{s}");
```

--------------------------------

### Split Vec Example

Source: https://docs.rs/fastanvil/0.32.0/fastanvil/tex/type.Texture.html

Demonstrates splitting a vector into two parts using `split_off`. The original vector retains elements up to the split point, and the new vector contains the remaining elements.

```rust
let mut vec = vec!['a', 'b', 'c'];
let vec2 = vec.split_off(1);
assert_eq!(vec, ['a']);
assert_eq!(vec2, ['b', 'c']);
```

--------------------------------

### Result Methods

Source: https://docs.rs/fastanvil/0.32.0/fastanvil/tex/type.Result.html

Examples and descriptions of common methods available on the Result type.

```APIDOC
## `sq_then_to_string` Example

### Description
Demonstrates chaining fallible operations using `and_then`.

### Code Example
```rust
fn sq_then_to_string(x: u32) -> Result<String, &'static str> {
    x.checked_mul(x).map(|sq| sq.to_string()).ok_or("overflowed")
}

assert_eq!(Ok(2).and_then(sq_then_to_string), Ok(4.to_string()));
assert_eq!(Ok(1_000_000).and_then(sq_then_to_string), Err("overflowed"));
assert_eq!(Err("not a number").and_then(sq_then_to_string), Err("not a number"));
```
```

```APIDOC
## `or` Method

### Description
Returns `res` if the result is `Err`, otherwise returns the `Ok` value of `self`. Arguments passed to `or` are eagerly evaluated.

### Method
`pub fn or<F>(self, res: Result<T, F>) -> Result<T, F>`

### Examples
```rust
let x: Result<u32, &str> = Ok(2);
let y: Result<u32, &str> = Err("late error");
assert_eq!(x.or(y), Ok(2));

let x: Result<u32, &str> = Err("early error");
let y: Result<u32, &str> = Ok(2);
assert_eq!(x.or(y), Ok(2));

let x: Result<u32, &str> = Err("not a 2");
let y: Result<u32, &str> = Err("late error");
assert_eq!(x.or(y), Err("late error"));

let x: Result<u32, &str> = Ok(2);
let y: Result<u32, &str> = Ok(100);
assert_eq!(x.or(y), Ok(2));
```
```

```APIDOC
## `or_else` Method

### Description
Calls `op` if the result is `Err`, otherwise returns the `Ok` value of `self`. This function can be used for control flow based on result values.

### Method
`pub fn or_else<F, O>(self, op: O) -> Result<T, F>` where O: FnOnce(E) -> Result<T, F>

### Examples
```rust
fn sq(x: u32) -> Result<u32, u32> { Ok(x * x) }
fn err(x: u32) -> Result<u32, u32> { Err(x) }

assert_eq!(Ok(2).or_else(sq).or_else(sq), Ok(2));
assert_eq!(Ok(2).or_else(err).or_else(sq), Ok(2));
assert_eq!(Err(3).or_else(sq).or_else(err), Ok(9));
assert_eq!(Err(3).or_else(err).or_else(err), Err(3));
```
```

```APIDOC
## `unwrap_or` Method

### Description
Returns the contained `Ok` value or a provided default. Arguments passed to `unwrap_or` are eagerly evaluated.

### Method
`pub fn unwrap_or(self, default: T) -> T`

### Examples
```rust
let default = 2;
let x: Result<u32, &str> = Ok(9);
assert_eq!(x.unwrap_or(default), 9);

let x: Result<u32, &str> = Err("error");
assert_eq!(x.unwrap_or(default), default);
```
```

```APIDOC
## `unwrap_or_else` Method

### Description
Returns the contained `Ok` value or computes it from a closure.

### Method
`pub fn unwrap_or_else<F>(self, op: F) -> T` where F: FnOnce(E) -> T

### Examples
```rust
fn count(x: &str) -> usize { x.len() }

assert_eq!(Ok(2).unwrap_or_else(count), 2);
assert_eq!(Err("foo").unwrap_or_else(count), 3);
```
```

```APIDOC
## `unwrap_unchecked` Method

### Description
Returns the contained `Ok` value, consuming the `self` value, without checking that the value is not an `Err`.

### Safety
Calling this method on an `Err` is _undefined behavior_.

### Method
`pub unsafe fn unwrap_unchecked(self) -> T`

### Examples
```rust
let x: Result<u32, &str> = Ok(2);
assert_eq!(unsafe { x.unwrap_unchecked() }, 2);
```

```rust
let x: Result<u32, &str> = Err("emergency failure");
unsafe { x.unwrap_unchecked() }; // Undefined behavior!
```
```

```APIDOC
## `unwrap_err_unchecked` Method

### Description
Returns the contained `Err` value, consuming the `self` value, without checking that the value is not an `Ok`.

### Safety
Calling this method on an `Ok` is _undefined behavior_.

### Method
`pub unsafe fn unwrap_err_unchecked(self) -> E`

### Examples
```rust
let x: Result<u32, &str> = Ok(2);
unsafe { x.unwrap_err_unchecked() }; // Undefined behavior!
```

```rust
let x: Result<u32, &str> = Err("emergency failure");
assert_eq!(unsafe { x.unwrap_err_unchecked() }, "emergency failure");
```
```

--------------------------------

### Iterate over block state indices

Source: https://docs.rs/fastanvil/0.32.0/fastanvil/pre18/struct.Pre18Blockstates.html

Example showing how to recover coordinates from the block state iterator.

```rust
for (i, block_index) in states.iter_indices(10).enumerate() {
    let x = i & 0x000F;
    let y = (i & 0x0F00) >> 8;
    let z = (i & 0x00F0) >> 4;
}
```

--------------------------------

### Result::copied Method

Source: https://docs.rs/fastanvil/0.32.0/fastanvil/type.Result.html

Examples of using the copied method on Result<&T, E> and Result<&mut T, E>.

```rust
let val = 12;
let x: Result<&i32, i32> = Ok(&val);
assert_eq!(x, Ok(&12));
let copied = x.copied();
assert_eq!(copied, Ok(12));
```

```rust
let mut val = 12;
let x: Result<&mut i32, i32> = Ok(&mut val);
assert_eq!(x, Ok(&mut 12));
let copied = x.copied();
assert_eq!(copied, Ok(12));
```

--------------------------------

### Result::cloned Method

Source: https://docs.rs/fastanvil/0.32.0/fastanvil/type.Result.html

Examples of using the cloned method on Result<&T, E> and Result<&mut T, E>.

```rust
let val = 12;
let x: Result<&i32, i32> = Ok(&val);
assert_eq!(x, Ok(&12));
let cloned = x.cloned();
assert_eq!(cloned, Ok(12));
```

```rust
let mut val = 12;
let x: Result<&mut i32, i32> = Ok(&mut val);
assert_eq!(x, Ok(&mut 12));
let cloned = x.cloned();
assert_eq!(cloned, Ok(12));
```

--------------------------------

### Renderer Initialization

Source: https://docs.rs/fastanvil/0.32.0/fastanvil/tex/struct.Renderer.html

Creates a new instance of the Renderer with provided blockstates, models, and textures.

```APIDOC
## pub fn new

### Description
Initializes a new Renderer instance with the required mapping data.

### Parameters
- **blockstates** (HashMap<String, Blockstate>) - Required - Map of blockstate identifiers to their definitions.
- **models** (HashMap<String, Model>) - Required - Map of model identifiers to their definitions.
- **textures** (HashMap<String, Texture>) - Required - Map of texture identifiers to their definitions.
```

--------------------------------

### Result::is_err Method

Source: https://docs.rs/fastanvil/0.32.0/fastanvil/type.Result.html

Example of checking if a Result is Err.

```rust
let x: Result<i32, &str> = Ok(-3);
assert_eq!(x.is_err(), false);

let x: Result<i32, &str> = Err("Some error message");
assert_eq!(x.is_err(), true);
```

--------------------------------

### Vec with Capacity and System Allocator

Source: https://docs.rs/fastanvil/0.32.0/fastanvil/tex/type.Texture.html

Demonstrates creating a Vec with a specific capacity using the System allocator and observing its behavior during element additions. Note that a vector of a zero-sized type will always over-allocate to usize::MAX.

```rust
#![feature(allocator_api)]

use std::alloc.System;

let mut vec = Vec::with_capacity_in(10, System);

// The vector contains no items, even though it has capacity for more
assert_eq!(vec.len(), 0);
assert!(vec.capacity() >= 10);

// These are all done without reallocating...
for i in 0..10 {
    vec.push(i);
}
assert_eq!(vec.len(), 10);
assert!(vec.capacity() >= 10);

// ...but this may make the vector reallocate
vec.push(11);
assert_eq!(vec.len(), 11);
assert!(vec.capacity() >= 11);

// A vector of a zero-sized type will always over-allocate, since no
// allocation is necessary
let vec_units = Vec::<(), System>::with_capacity_in(10, System);
assert_eq!(vec_units.capacity(), usize::MAX);
```

--------------------------------

### Get Vec Length

Source: https://docs.rs/fastanvil/0.32.0/fastanvil/tex/type.Texture.html

Returns the number of elements currently in the vector.

```rust
let a = vec![1, 2, 3];
assert_eq!(a.len(), 3);

```

--------------------------------

### RegionFileLoader Methods

Source: https://docs.rs/fastanvil/0.32.0/fastanvil/struct.RegionFileLoader.html

Methods for initializing the loader and interacting with region files.

```APIDOC
## new(region_dir: PathBuf)

### Description
Creates a new RegionFileLoader instance pointing to the specified directory.

### Parameters
- **region_dir** (PathBuf) - Required - The directory path containing region files.

## has_region(x: RCoord, z: RCoord)

### Description
Checks if a region file exists for the given coordinates.

### Parameters
- **x** (RCoord) - Required - The X coordinate of the region.
- **z** (RCoord) - Required - The Z coordinate of the region.

### Response
- **bool** - Returns true if the region exists, false otherwise.

## region(x: RCoord, z: RCoord)

### Description
Retrieves a specific region file. Returns Ok(None) if the region does not exist.

### Parameters
- **x** (RCoord) - Required - The X coordinate of the region.
- **z** (RCoord) - Required - The Z coordinate of the region.

### Response
- **LoaderResult<Option<Region<File>>>** - The region object or None.

## list()

### Description
Lists all regions available to this loader.

### Response
- **LoaderResult<Vec<(RCoord, RCoord)>>** - A list of coordinate pairs for available regions.
```

--------------------------------

### Get Chunk Y Range

Source: https://docs.rs/fastanvil/0.32.0/fastanvil/enum.JavaChunk.html

Returns the valid range of Y values for this chunk.

```rust
fn y_range(&self) -> Range<isize>
```

--------------------------------

### Vec with Custom Allocator

Source: https://docs.rs/fastanvil/0.32.0/fastanvil/tex/type.Texture.html

Demonstrates creating a Vec with a custom allocator and converting it back to its components.

```rust
#![feature(allocator_api)]

use std::alloc::System;

let mut v: Vec<i32, System> = Vec::new_in(System);
v.push(-1);
v.push(0);
v.push(1);

let (ptr, len, cap, alloc) = v.into_parts_with_alloc();

let rebuilt = unsafe {
    // We can now make changes to the components, such as
    // transmuting the raw pointer to a compatible type.
    let ptr = ptr.cast::<u32>();

    Vec::from_parts_in(ptr, len, cap, alloc)
};
assert_eq!(rebuilt, [4294967295, 0, 1]);

```

--------------------------------

### TopShadeRenderer::new

Source: https://docs.rs/fastanvil/0.32.0/fastanvil/struct.TopShadeRenderer.html

Constructs a new TopShadeRenderer instance.

```APIDOC
## TopShadeRenderer::new

### Description
Constructs a new `TopShadeRenderer` instance.

### Method
`pub fn new(palette: &'a P, mode: HeightMode) -> Self`

### Parameters
#### Path Parameters
None

#### Query Parameters
None

#### Request Body
None

### Request Example
None

### Response
#### Success Response (200)
- **Self** (TopShadeRenderer) - A new instance of TopShadeRenderer.

#### Response Example
None
```

--------------------------------

### Vec::with_capacity_in

Source: https://docs.rs/fastanvil/0.32.0/fastanvil/tex/type.Texture.html

Constructs a new, empty Vec with a specified initial capacity and allocator. This is a nightly-only experimental API.

```APIDOC
## POST /vec/with_capacity_in

### Description
Constructs a new, empty `Vec<T, A>` with at least the specified capacity and the provided allocator. The vector will be able to hold at least `capacity` elements without reallocating. This method is allowed to allocate for more elements than `capacity`. If `capacity` is zero, the vector will not allocate.

It is important to note that although the returned vector has the minimum _capacity_ specified, the vector will have a zero _length_. For an explanation of the difference between length and capacity, see _Capacity and reallocation_.
If it is important to know the exact allocated capacity of a `Vec`, always use the `capacity` method after construction.
For `Vec<T, A>` where `T` is a zero-sized type, there will be no allocation and the capacity will always be `usize::MAX`.

### Method
POST

### Endpoint
/vec/with_capacity_in

### Parameters
#### Path Parameters
None

#### Query Parameters
None

#### Request Body
- **capacity** (usize) - Required - The minimum capacity for the new vector.
- **alloc** (A) - Required - The allocator to use for the vector.

### Request Example
```json
{
  "capacity": 10,
  "alloc": "System"
}
```

### Response
#### Success Response (200)
- **Vec<T, A>** - A new, empty vector with the specified capacity and allocator.

#### Response Example
```json
{
  "vec": []
}
```

##### §Panics
Panics if the new capacity exceeds `isize::MAX` _bytes_.
```

--------------------------------

### Get Type ID

Source: https://docs.rs/fastanvil/0.32.0/fastanvil/enum.JavaChunk.html

Returns the TypeId of the current type. This is part of the Any trait implementation.

```rust
fn type_id(&self) -> TypeId
```

--------------------------------

### Renderer Constructor

Source: https://docs.rs/fastanvil/0.32.0/fastanvil/tex/struct.Renderer.html

Initializes a new Renderer instance. Requires HashMaps for blockstates, models, and textures.

```rust
pub fn new( blockstates: HashMap<String, Blockstate>, models: HashMap<String, Model>, textures: HashMap<String, Texture>, ) -> Self
```

--------------------------------

### Get Immutable Slice of Vec

Source: https://docs.rs/fastanvil/0.32.0/fastanvil/tex/type.Texture.html

Extracts a slice containing the entire vector. Equivalent to `&s[..]`.

```rust
use std::io::{self, Write};
let buffer = vec![1, 2, 3, 5, 8];
io::sink().write(buffer.as_slice()).unwrap();
```

--------------------------------

### Get Top Texture

Source: https://docs.rs/fastanvil/0.32.0/fastanvil/tex/struct.Renderer.html

Retrieves the top texture for a given block ID and encoded properties.

```APIDOC
## fn get_top

### Description
Retrieves the top texture associated with a specific block ID and its encoded properties.

### Parameters
- **id** (str) - Required - The block identifier.
- **encoded_props** (str) - Required - The encoded properties string for the block.

### Response
- **Result<Texture>** - Returns the texture or an error if the operation fails.
```

--------------------------------

### RegionLoader.list Method

Source: https://docs.rs/fastanvil/0.32.0/fastanvil/trait.RegionLoader.html

Lists all regions that the loader can return. Implementations must provide this to allow efficient processing of regions.

```rust
fn list(&self) -> LoaderResult<Vec<(RCoord, RCoord)>>;
```

--------------------------------

### Get Immutable Chunk Reference

Source: https://docs.rs/fastanvil/0.32.0/fastanvil/struct.RegionMap.html

Provides immutable access to a specific chunk within the RegionMap.

```rust
pub fn chunk(&self, x: CCoord, z: CCoord) -> &[T]>
```

--------------------------------

### Get Mutable Chunk Reference

Source: https://docs.rs/fastanvil/0.32.0/fastanvil/struct.RegionMap.html

Provides mutable access to a specific chunk within the RegionMap.

```rust
pub fn chunk_mut(&mut self, x: CCoord, z: CCoord) -> &mut [T]>
```

--------------------------------

### Result Implementations

Source: https://docs.rs/fastanvil/0.32.0/fastanvil/type.Result.html

Provides documentation for various implementations of the Result type, showcasing different methods and their usage.

```APIDOC
## Implementations

### `impl<T, E> Result<&T, E>`

#### `pub const fn copied(self) -> Result<T, E>`

Maps a `Result<&T, E>` to a `Result<T, E>` by copying the contents of the `Ok` part.

##### Examples
```rust
let val = 12;
let x: Result<&i32, i32> = Ok(&val);
assert_eq!(x, Ok(&12));
let copied = x.copied();
assert_eq!(copied, Ok(12));
```

#### `pub fn cloned(self) -> Result<T, E>`

Maps a `Result<&T, E>` to a `Result<T, E>` by cloning the contents of the `Ok` part.

##### Examples
```rust
let val = 12;
let x: Result<&i32, i32> = Ok(&val);
assert_eq!(x, Ok(&12));
let cloned = x.cloned();
assert_eq!(cloned, Ok(12));
```

### `impl<T, E> Result<&mut T, E>`

#### `pub const fn copied(self) -> Result<T, E>`

Maps a `Result<&mut T, E>` to a `Result<T, E>` by copying the contents of the `Ok` part.

##### Examples
```rust
let mut val = 12;
let x: Result<&mut i32, i32> = Ok(&mut val);
assert_eq!(x, Ok(&mut 12));
let copied = x.copied();
assert_eq!(copied, Ok(12));
```

#### `pub fn cloned(self) -> Result<T, E>`

Maps a `Result<&mut T, E>` to a `Result<T, E>` by cloning the contents of the `Ok` part.

##### Examples
```rust
let mut val = 12;
let x: Result<&mut i32, i32> = Ok(&mut val);
assert_eq!(x, Ok(&mut 12));
let cloned = x.cloned();
assert_eq!(cloned, Ok(12));
```

### `impl<T, E> Result<Option<T>, E>`

#### `pub const fn transpose(self) -> Option<Result<T, E>>`

Transposes a `Result` of an `Option` into an `Option` of a `Result`.
`Ok(None)` will be mapped to `None`. `Ok(Some(_))` and `Err(_)` will be mapped to `Some(Ok(_))` and `Some(Err(_))`.

##### Examples
```rust
#[derive(Debug, Eq, PartialEq)]
struct SomeErr;

let x: Result<Option<i32>, SomeErr> = Ok(Some(5));
let y: Option<Result<i32, SomeErr>> = Some(Ok(5));
assert_eq!(x.transpose(), y);
```

### `impl<T, E> Result<Result<T, E>, E>`

#### `pub const fn flatten(self) -> Result<T, E>`

Converts from `Result<Result<T, E>, E>` to `Result<T, E>`.

##### Examples
```rust
let x: Result<Result<&'static str, u32>, u32> = Ok(Ok("hello"));
assert_eq!(Ok("hello"), x.flatten());

let x: Result<Result<&'static str, u32>, u32> = Ok(Err(6));
assert_eq!(Err(6), x.flatten());

let x: Result<Result<&'static str, u32>, u32> = Err(6);
assert_eq!(Err(6), x.flatten());
```

Flattening only removes one level of nesting at a time:
```rust
let x: Result<Result<Result<&'static str, u32>, u32>, u32> = Ok(Ok(Ok("hello")));
assert_eq!(Ok(Ok("hello")), x.flatten());
assert_eq!(Ok("hello"), x.flatten().flatten());
```

### `impl<T, E> Result<T, E>`

#### `pub const fn is_ok(&self) -> bool`

Returns `true` if the result is `Ok`.

##### Examples
```rust
let x: Result<i32, &str> = Ok(-3);
assert_eq!(x.is_ok(), true);

let x: Result<i32, &str> = Err("Some error message");
assert_eq!(x.is_ok(), false);
```

#### `pub fn is_ok_and<F>(self, f: F) -> bool` where F: FnOnce(T) -> bool

Returns `true` if the result is `Ok` and the value inside of it matches a predicate.

##### Examples
```rust
let x: Result<u32, &str> = Ok(2);
assert_eq!(x.is_ok_and(|x| x > 1), true);

let x: Result<u32, &str> = Ok(0);
assert_eq!(x.is_ok_and(|x| x > 1), false);

let x: Result<u32, &str> = Err("hey");
assert_eq!(x.is_ok_and(|x| x > 1), false);

let x: Result<String, &str> = Ok("ownership".to_string());
assert_eq!(x.as_ref().is_ok_and(|x| x.len() > 1), true);
println!("still alive {:?}", x);
```

#### `pub const fn is_err(&self) -> bool`

Returns `true` if the result is `Err`.

##### Examples
```rust
let x: Result<i32, &str> = Ok(-3);
assert_eq!(x.is_err(), false);

let x: Result<i32, &str> = Err("Some error message");
assert_eq!(x.is_err(), true);
```

#### `pub fn is_err_and<F>(self, f: F) -> bool` where F: FnOnce(E) -> bool

Returns `true` if the result is `Err` and the value inside of it matches a predicate.
```

--------------------------------

### Create Vec with Capacity and Allocator (Nightly)

Source: https://docs.rs/fastanvil/0.32.0/fastanvil/tex/type.Texture.html

Constructs a new, empty Vec<T, A> with a specified initial capacity and allocator. Returns an error if capacity is too large or allocation fails.

```APIDOC
## pub fn try_with_capacity_in( capacity: usize, alloc: A, ) -> Result<Vec<T, A>, TryReserveError>

### Description
Constructs a new, empty `Vec<T, A>` with at least the specified capacity with the provided allocator. The vector will be able to hold at least `capacity` elements without reallocating. This method is allowed to allocate for more elements than `capacity`. If `capacity` is zero, the vector will not allocate.

### Method
Associated function

### Endpoint
N/A (function call)

### Parameters
- **capacity** (usize) - The minimum initial capacity for the vector.
- **alloc** (A) - The allocator to be used for this vector.

### Request Example
```rust
#![feature(allocator_api)]
use std::alloc::System;
let result: Result<Vec<i32, _>, _> = Vec::try_with_capacity_in(10, System);
```

### Response
- **Ok(Vec<T, A>)** - A new vector with the specified capacity and allocator.
- **Err(TryReserveError)** - An error if the capacity exceeds `isize::MAX` bytes or if the allocator reports failure.
```

--------------------------------

### Create Vec with capacity (experimental)

Source: https://docs.rs/fastanvil/0.32.0/fastanvil/tex/type.Texture.html

Constructs a new, empty Vec with at least the specified capacity, returning a Result to handle potential allocation errors. This is a nightly-only experimental API.

```rust
pub fn try_with_capacity(capacity: usize) -> Result<Vec<T>, TryReserveError>
```

--------------------------------

### Get Mutable Slice of Vec

Source: https://docs.rs/fastanvil/0.32.0/fastanvil/tex/type.Texture.html

Extracts a mutable slice of the entire vector. Equivalent to `&mut s[..]`.

```rust
use std::io::{self, Read};
let mut buffer = vec![0; 3];
io::repeat(0b101).read_exact(buffer.as_mut_slice()).unwrap();
```

--------------------------------

### Lz4DecoderWrapper Initialization

Source: https://docs.rs/fastanvil/0.32.0/fastanvil/struct.Lz4DecoderWrapper.html

Creates a new instance of Lz4DecoderWrapper which wraps a writer.

```APIDOC
## Lz4DecoderWrapper::new

### Description
Creates a new Lz4DecoderWrapper instance that writes to the provided writer.

### Parameters
#### Request Body
- **write_to** (W: Write) - Required - The writer to which the decompressed data will be written.
```

--------------------------------

### Unwrap Err value

Source: https://docs.rs/fastanvil/0.32.0/fastanvil/tex/type.Result.html

Use `unwrap_err()` to get the contained `Err` value. Panics if the value is an `Ok`.

```rust
let x: Result<u32, &str> = Ok(2);
x.unwrap_err(); // panics with `2`
```

```rust
let x: Result<u32, &str> = Err("emergency failure");
assert_eq!(x.unwrap_err(), "emergency failure");
```

--------------------------------

### Implementations for Result<Option<T>, E>

Source: https://docs.rs/fastanvil/0.32.0/fastanvil/type.LoaderResult.html

Provides implementations for Result<Option<T>, E>, including the `transpose` method.

```APIDOC
### impl<T, E> Result<Option<T>, E>

#### pub const fn transpose(self) -> Option<Result<T, E>>
Transposes a `Result` of an `Option` into an `Option` of a `Result`.
`Ok(None)` will be mapped to `None`. `Ok(Some(_))` and `Err(_)` will be mapped to `Some(Ok(_))` and `Some(Err(_))`.

##### §Examples
```rust
#[derive(Debug, Eq, PartialEq)]
struct SomeErr;

let x: Result<Option<i32>, SomeErr> = Ok(Some(5));
let y: Option<Result<i32, SomeErr>> = Some(Ok(5));
assert_eq!(x.transpose(), y);
```
```

--------------------------------

### Unwrap Ok value

Source: https://docs.rs/fastanvil/0.32.0/fastanvil/tex/type.Result.html

Use `unwrap()` to get the contained `Ok` value. Panics if the value is an `Err`.

```rust
let x: Result<u32, &str> = Ok(2);
assert_eq!(x.unwrap(), 2);
```

--------------------------------

### Resize Vec with Closure

Source: https://docs.rs/fastanvil/0.32.0/fastanvil/tex/type.Texture.html

Shows how to resize a vector in-place using `resize_with`. New elements are generated by a provided closure. If `new_len` is greater than `len`, the vector is extended; otherwise, it's truncated.

```rust
let mut vec = vec![1, 2, 3];
vec.resize_with(5, Default::default);
assert_eq!(vec, [1, 2, 3, 0, 0]);
```

```rust
let mut vec = vec![];
let mut p = 1;
vec.resize_with(4, || { p *= 2; p });
assert_eq!(vec, [2, 4, 8, 16]);
```

--------------------------------

### Get Chunk Status

Source: https://docs.rs/fastanvil/0.32.0/fastanvil/enum.JavaChunk.html

Retrieves the status of the chunk as a string. This method is part of the Chunk trait implementation for JavaChunk.

```rust
fn status(&self) -> String
```

--------------------------------

### Vec Capacity Check

Source: https://docs.rs/fastanvil/0.32.0/fastanvil/tex/type.Texture.html

Shows how to check the capacity of a Vec and asserts that it meets a minimum requirement.

```rust
let mut vec: Vec<i32> = Vec::with_capacity(10);
vec.push(42);
assert!(vec.capacity() >= 10);

```

--------------------------------

### CloneToUninit Trait Implementation

Source: https://docs.rs/fastanvil/0.32.0/fastanvil/struct.Region.html

Details the nightly-only experimental blanket implementation of `CloneToUninit` for types implementing `Clone`.

```APIDOC
## impl<T> CloneToUninit for T

### Description
Nightly-only experimental blanket implementation of the `CloneToUninit` trait for types implementing `Clone`.

### Method
`clone_to_uninit`

### Endpoint
N/A (Trait Implementation)

### Parameters
- **dest** (*mut u8) - The destination pointer to copy the data to.

### Request Body
N/A

### Response
N/A (Unsafe function)

### Response Example
N/A
```

--------------------------------

### Get Top Texture

Source: https://docs.rs/fastanvil/0.32.0/fastanvil/tex/struct.Renderer.html

Retrieves the top texture for a given ID and encoded properties. Returns a Result containing the Texture or an error.

```rust
fn get_top(&mut self, id: &str, encoded_props: &str) -> Result<Texture>
```

--------------------------------

### Iterator Adapters: take, scan, flat_map, flatten, map_windows, fuse, inspect, by_ref

Source: https://docs.rs/fastanvil/0.32.0/fastanvil/struct.RegionIter.html

These methods adapt existing iterators to provide new iteration behaviors.

```APIDOC
## Iterator Adapters

### `take(n)`

Creates an iterator that yields the first `n` elements, or fewer if the underlying iterator ends sooner.

### `scan(initial_state, f)`

An iterator adapter which, like `fold`, holds internal state, but unlike `fold`, produces a new iterator.

### `flat_map(f)`

Creates an iterator that works like map, but flattens nested structure.

### `flatten()`

Creates an iterator that flattens nested structure.

### `map_windows(f, N)`

Calls the given function `f` for each contiguous window of size `N` over `self` and returns an iterator over the outputs of `f`. Like `slice::windows()`, the windows during mapping overlap as well. (Nightly-only experimental API)

### `fuse()`

Creates an iterator which ends after the first `None`.

### `inspect(f)`

Does something with each element of an iterator, passing the value on.

### `by_ref()`

Creates a “by reference” adapter for this instance of `Iterator`.
```

--------------------------------

### Safely get Err value (nightly)

Source: https://docs.rs/fastanvil/0.32.0/fastanvil/tex/type.Result.html

The `into_err()` method returns the contained `Err` value and is guaranteed not to panic. This is a nightly-only experimental API.

```rust
fn only_bad_news() -> Result<!, String> {
    Err("Oops, it failed".into())
}

let error: String = only_bad_news().into_err();
println!("{error}");
```

--------------------------------

### Get Block at Coordinate

Source: https://docs.rs/fastanvil/0.32.0/fastanvil/enum.JavaChunk.html

Retrieves the block at the specified X, Y, and Z coordinates. Returns None if the section of the chunk at the given height is not present.

```rust
fn block(&self, x: usize, y: isize, z: usize) -> Option<&Block>
```

--------------------------------

### Implementations for Result<&mut T, E>

Source: https://docs.rs/fastanvil/0.32.0/fastanvil/type.LoaderResult.html

Provides implementations for Result<&mut T, E>, including `copied` and `cloned` methods.

```APIDOC
### impl<T, E> Result<&mut T, E>

#### pub const fn copied(self) -> Result<T, E>
where T: Copy,
Maps a `Result<&mut T, E>` to a `Result<T, E>` by copying the contents of the `Ok` part.

##### §Examples
```rust
let mut val = 12;
let x: Result<&mut i32, i32> = Ok(&mut val);
assert_eq!(x, Ok(&mut 12));
let copied = x.copied();
assert_eq!(copied, Ok(12));
```

#### pub fn cloned(self) -> Result<T, E>
where T: Clone,
Maps a `Result<&mut T, E>` to a `Result<T, E>` by cloning the contents of the `Ok` part.

##### §Examples
```rust
let mut val = 12;
let x: Result<&mut i32, i32> = Ok(&mut val);
assert_eq!(x, Ok(&mut 12));
let cloned = x.cloned();
assert_eq!(cloned, Ok(12));
```
```

--------------------------------

### Get Biome at Coordinate

Source: https://docs.rs/fastanvil/0.32.0/fastanvil/enum.JavaChunk.html

Retrieves the biome at the specified X, Y, and Z coordinates. Returns None if the section of the chunk at the given height is not present.

```rust
fn biome(&self, x: usize, y: isize, z: usize) -> Option<Biome>
```

--------------------------------

### Structs in pre13 Module

Source: https://docs.rs/fastanvil/0.32.0/fastanvil/pre13/index.html

Overview of the key structures defined in the pre13 module for representing Minecraft chunk data.

```APIDOC
## Structs

### JavaChunk

A Minecraft chunk.

### Level

A level describes the contents of the chunk in the world.

### Pre13Section

A vertical section of a chunk (ie a 16x16x16 block cube), for before 1.13.

### RawBlock

Raw block representation: block_id:data_value
```

--------------------------------

### Create Vec from Raw Parts with Custom Allocator (Nightly)

Source: https://docs.rs/fastanvil/0.32.0/fastanvil/tex/type.Texture.html

Use `from_raw_parts_in` to create a Vec from a raw pointer, length, capacity, and a specified allocator.

```rust
#![feature(allocator_api)]

let ptr = std::ptr::null_mut();
let len = 0;
let cap = 10;
let vec: Vec<i32, _> = unsafe { Vec::from_raw_parts_in(ptr, len, cap, System) };
```

--------------------------------

### ChunkLocation Struct Definition

Source: https://docs.rs/fastanvil/0.32.0/fastanvil/struct.ChunkLocation.html

Defines the structure for a chunk's location within a region file, specifying its starting offset and size in sectors.

```rust
pub struct ChunkLocation {
    pub offset: u64,
    pub sectors: u64,
}
```

--------------------------------

### TryFrom and TryInto Trait Implementations

Source: https://docs.rs/fastanvil/0.32.0/fastanvil/struct.Region.html

Covers the blanket implementations for `TryFrom<U>` for `T` and `TryInto<U>` for `T`.

```APIDOC
## impl<T, U> TryFrom<U> for T

### Description
Blanket implementation of the `TryFrom<U>` trait for type `T`, provided `U` implements `Into<T>`.

### Method
`try_from`

### Endpoint
N/A (Trait Implementation)

### Parameters
- **value** (U) - The value to convert.

### Request Body
N/A

### Response
#### Success Response (200)
- **Result<T, Infallible>** (Result<T, Infallible>) - The result of the conversion.

### Response Example
N/A (Method Call)

## impl<T, U> TryInto<U> for T

### Description
Blanket implementation of the `TryInto<U>` trait for type `T`, provided `U` implements `TryFrom<T>`.

### Method
`try_into`

### Endpoint
N/A (Trait Implementation)

### Parameters
N/A

### Request Body
N/A

### Response
#### Success Response (200)
- **Result<U, <U as TryFrom<T>>::Error>** (Result<U, <U as TryFrom<T>>::Error>) - The result of the conversion.

### Response Example
N/A (Method Call)
```

--------------------------------

### Expect Err value with custom panic message

Source: https://docs.rs/fastanvil/0.32.0/fastanvil/tex/type.Result.html

Use `expect_err()` to get the contained `Err` value. Panics with a custom message if the value is an `Ok`.

```rust
let x: Result<u32, &str> = Ok(10);
x.expect_err("Testing expect_err"); // panics with `Testing expect_err: 10`
```

--------------------------------

### Construct Vec with Capacity and Allocator

Source: https://docs.rs/fastanvil/0.32.0/fastanvil/tex/type.Texture.html

Constructs a new, empty `Vec<T, A>` with at least the specified capacity and a provided allocator. This is a nightly-only experimental API.

```rust
pub const fn with_capacity_in(capacity: usize, alloc: A) -> Vec<T, A>
```

--------------------------------

### Implement Iterator for StatesIter

Source: https://docs.rs/fastanvil/0.32.0/fastanvil/struct.StatesIter.html

Core iterator functionality for StatesIter. This includes methods for advancing the iterator, getting the next item, and determining size hints.

```rust
impl<'a> Iterator for StatesIter<'a>
```

```rust
type Item = usize
```

```rust
fn next(&mut self) -> Option<Self::Item>
```

```rust
fn size_hint(&self) -> (usize, Option<usize>)
```

--------------------------------

### From and Into Trait Implementations

Source: https://docs.rs/fastanvil/0.32.0/fastanvil/struct.Region.html

Describes the blanket implementations for `From<T>` for `T` and `Into<U>` for `T` where `U` implements `From<T>`.

```APIDOC
## impl<T> From<T> for T

### Description
Blanket implementation of the `From<T>` trait for type `T` itself.

### Method
`from`

### Endpoint
N/A (Trait Implementation)

### Parameters
- **t** (T) - The value to convert.

### Request Body
N/A

### Response
#### Success Response (200)
- **T** (T) - The argument unchanged.

### Response Example
N/A (Method Call)

## impl<T, U> Into<U> for T

### Description
Blanket implementation of the `Into<U>` trait for type `T`, provided `U` implements `From<T>`.

### Method
`into`

### Endpoint
N/A (Trait Implementation)

### Parameters
N/A

### Request Body
N/A

### Response
#### Success Response (200)
- **U** (U) - The result of `U::from(self)`.

### Response Example
N/A (Method Call)
```

--------------------------------

### Implement ExactSizeIterator for StatesIter

Source: https://docs.rs/fastanvil/0.32.0/fastanvil/struct.StatesIter.html

Provides exact size information for the StatesIter iterator. This includes methods to get the remaining length and check if the iterator is empty.

```rust
impl<'a> ExactSizeIterator for StatesIter<'a>
```

```rust
fn len(&self) -> usize
```

```rust
fn is_empty(&self) -> bool
```

--------------------------------

### SectionLike Trait Definition

Source: https://docs.rs/fastanvil/0.32.0/fastanvil/trait.SectionLike.html

Defines the SectionLike trait with required methods for checking terminators and getting the y-coordinate. Implementations are provided for Pre13Section, Pre18Section, and Section.

```rust
pub trait SectionLike {
    // Required methods
    fn is_terminator(&self) -> bool;
    fn y(&self) -> i8;
}
```

--------------------------------

### load_rendered_palette

Source: https://docs.rs/fastanvil/0.32.0/fastanvil/fn.load_rendered_palette.html

Loads a prepared rendered palette from a reader, typically used with palette.tar.gz files.

```APIDOC
## Function load_rendered_palette

### Description
Loads a prepared rendered palette. This is intended for use with the palette.tar.gz file found in the fastnbt project repository.

### Signature
`pub fn load_rendered_palette(palette: impl Read) -> Result<RenderedPalette, PaletteError>`

### Parameters
- **palette** (impl Read) - Required - A reader providing the palette data.

### Response
- **Result<RenderedPalette, PaletteError>** - Returns a RenderedPalette on success, or a PaletteError if the loading fails.
```

--------------------------------

### Chain fallible operations with and_then

Source: https://docs.rs/fastanvil/0.32.0/fastanvil/tex/type.Result.html

Use and_then to chain operations that return a Result. The provided examples demonstrate handling successful results and error propagation.

```rust
fn sq_then_to_string(x: u32) -> Result<String, &'static str> {
    x.checked_mul(x).map(|sq| sq.to_string()).ok_or("overflowed")
}

assert_eq!(Ok(2).and_then(sq_then_to_string), Ok(4.to_string()));
assert_eq!(Ok(1_000_000).and_then(sq_then_to_string), Err("overflowed"));
assert_eq!(Err("not a number").and_then(sq_then_to_string), Err("not a number"));
```

```rust
use std::{io::ErrorKind, path::Path};

// Note: on Windows "/" maps to "C:\"
let root_modified_time = Path::new("/").metadata().and_then(|md| md.modified());
assert!(root_modified_time.is_ok());

let should_fail = Path::new("/bad/path").metadata().and_then(|md| md.modified());
assert!(should_fail.is_err());
assert_eq!(should_fail.unwrap_err().kind(), ErrorKind::NotFound);
```

--------------------------------

### Region Initialization and Reading

Source: https://docs.rs/fastanvil/0.32.0/fastanvil/struct.Region.html

Methods for loading a region from a stream and reading specific chunk data.

```APIDOC
## from_stream

### Description
Loads a region from an existing stream (e.g., File or Cursor). Assumes a seek of zero is the start of the region.

### Parameters
#### Request Body
- **stream** (S: Read + Seek) - Required - The underlying stream to read from.

## read_chunk

### Description
Reads the chunk located at the specified coordinates. Returns uncompressed NBT data.

### Parameters
#### Path Parameters
- **x** (usize) - Required - Chunk X coordinate (0-31).
- **z** (usize) - Required - Chunk Z coordinate (0-31).

### Response
#### Success Response (200)
- **Option<Vec<u8>>** - The uncompressed NBT data of the chunk, or None if the chunk does not exist.
```

--------------------------------

### Fastanvil Module Documentation

Source: https://docs.rs/fastanvil/0.32.0/fastanvil/complete/index.html

Overview of the fastanvil module, including its structs and features.

```APIDOC
## Module: fastanvil

This module provides functionality for working with anvil files.

### Structs

#### Chunk

A struct representing a chunk within an anvil file. Further details about its fields and methods are not provided in the source text.
```

--------------------------------

### Unwrap or return default

Source: https://docs.rs/fastanvil/0.32.0/fastanvil/tex/type.Result.html

Use `unwrap_or_default()` to get the contained `Ok` value or the default value if it's an `Err`. Requires the error type to implement `Default`.

```rust
let good_year_from_input = "1909";
let bad_year_from_input = "190blarg";
let good_year = good_year_from_input.parse().unwrap_or_default();
let bad_year = bad_year_from_input.parse().unwrap_or_default();

assert_eq!(1909, good_year);
assert_eq!(0, bad_year);
```

--------------------------------

### Vec Implementations for Texture

Source: https://docs.rs/fastanvil/0.32.0/fastanvil/tex/type.Texture.html

Details common Vec methods applicable to Texture, such as new(), with_capacity(), try_with_capacity(), and from_raw_parts().

```APIDOC
## Implementations

### impl<T> Vec<T>

#### pub const fn new() -> Vec<T>

Constructs a new, empty `Vec<T>`.

##### §Examples
```rust
let mut vec: Vec<i32> = Vec::new();
```

#### pub fn with_capacity(capacity: usize) -> Vec<T>

Constructs a new, empty `Vec<T>` with at least the specified capacity.

##### §Panics
Panics if the new capacity exceeds `isize::MAX` _bytes_.

##### §Examples
```rust
let mut vec = Vec::with_capacity(10);
assert_eq!(vec.len(), 0);
assert!(vec.capacity() >= 10);

for i in 0..10 {
    vec.push(i);
}
assert_eq!(vec.len(), 10);
assert!(vec.capacity() >= 10);

vec.push(11);
assert_eq!(vec.len(), 11);
assert!(vec.capacity() >= 11);

let vec_units = Vec::<()>::with_capacity(10);
assert_eq!(vec_units.capacity(), usize::MAX);
```

#### pub fn try_with_capacity(capacity: usize) -> Result<Vec<T>, TryReserveError>

Constructs a new, empty `Vec<T>` with at least the specified capacity.

##### §Errors
Returns an error if the capacity exceeds `isize::MAX` _bytes_ , or if the allocator reports allocation failure.

#### pub unsafe fn from_raw_parts( ptr: *mut T, length: usize, capacity: usize, ) -> Vec<T>

Creates a `Vec<T>` directly from a pointer, a length, and a capacity.
```

--------------------------------

### Deconstruct and Reconstruct Vec<T>

Source: https://docs.rs/fastanvil/0.32.0/fastanvil/tex/type.Texture.html

Use `into_raw_parts` to get the pointer, length, and capacity of a Vec. This is useful for manual memory manipulation before reconstructing the Vec using `Vec::from_raw_parts`.

```rust
use std::ptr;

let v = vec![1, 2, 3];

// Deconstruct the vector into parts.
let (p, len, cap) = v.into_raw_parts();

unsafe {
    // Overwrite memory with 4, 5, 6
    for i in 0..len {
        ptr::write(p.add(i), 4 + i);
    }

    // Put everything back together into a Vec
    let rebuilt = Vec::from_raw_parts(p, len, cap);
    assert_eq!(rebuilt, [4, 5, 6]);
}
```
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