Struct image::ImageBuffer

pub struct ImageBuffer<P: Pixel, Container> { /* fields omitted */ }

Generic image buffer

Methods

impl<P, Container> ImageBuffer<P, Container> where
    P: Pixel + 'static,
    P::Subpixel: 'static,
    Container: Deref<Target = [P::Subpixel]>, 

pub fn from_raw(
    width: u32,
    height: u32,
    buf: Container
) -> Option<ImageBuffer<P, Container>>

Contructs a buffer from a generic container (for example a Vec or a slice)

Returns None if the container is not big enough

pub fn into_raw(self) -> Container

Returns the underlying raw buffer

pub fn dimensions(&self) -> (u32, u32)

The width and height of this image.

pub fn width(&self) -> u32

The width of this image.

pub fn height(&self) -> u32

The height of this image.

pub fn pixels(&self) -> Pixels<P>

Returns an iterator over the pixels of this image.

pub fn enumerate_pixels(&self) -> EnumeratePixels<P>

Enumerates over the pixels of the image. The iterator yields the coordinates of each pixel along with a reference to them.

pub fn get_pixel(&self, x: u32, y: u32) -> &P

Gets a reference to the pixel at location (x, y)

Panics

Panics if (x, y) is out of the bounds (width, height).

impl<P, Container> ImageBuffer<P, Container> where
    P: Pixel + 'static,
    P::Subpixel: 'static,
    Container: Deref<Target = [P::Subpixel]> + DerefMut, 

pub fn pixels_mut(&mut self) -> PixelsMut<P>

Returns an iterator over the mutable pixels of this image.

pub fn enumerate_pixels_mut(&mut self) -> EnumeratePixelsMut<P>

Enumerates over the pixels of the image. The iterator yields the coordinates of each pixel along with a mutable reference to them.

pub fn get_pixel_mut(&mut self, x: u32, y: u32) -> &mut P

Gets a reference to the mutable pixel at location (x, y)

Panics

Panics if (x, y) is out of the bounds (width, height).

pub fn put_pixel(&mut self, x: u32, y: u32, pixel: P)

Puts a pixel at location (x, y)

Panics

Panics if (x, y) is out of the bounds (width, height).

impl<P, Container> ImageBuffer<P, Container> where
    P: Pixel<Subpixel = u8> + 'static,
    Container: Deref<Target = [u8]>, 

pub fn save<Q>(&self, path: Q) -> Result<()> where
    Q: AsRef<Path>, 

Saves the buffer to a file at the path specified.

The image format is derived from the file extension. Currently only jpeg and png files are supported.

impl<P: Pixel + 'static> ImageBuffer<P, Vec<P::Subpixel>> where
    P::Subpixel: 'static, 

pub fn new(width: u32, height: u32) -> ImageBuffer<P, Vec<P::Subpixel>>

Creates a new image buffer based on a Vec<P::Subpixel>.

pub fn from_pixel(
    width: u32,
    height: u32,
    pixel: P
) -> ImageBuffer<P, Vec<P::Subpixel>>

Constructs a new ImageBuffer by copying a pixel

pub fn from_fn<F>(
    width: u32,
    height: u32,
    f: F
) -> ImageBuffer<P, Vec<P::Subpixel>> where
    F: FnMut(u32, u32) -> P, 

Constructs a new ImageBuffer by repeated application of the supplied function. The arguments to the function are the pixel's x and y coordinates.

pub fn from_vec(
    width: u32,
    height: u32,
    buf: Vec<P::Subpixel>
) -> Option<ImageBuffer<P, Vec<P::Subpixel>>>

Creates an image buffer out of an existing buffer. Returns None if the buffer is not big enough.

pub fn into_vec(self) -> Vec<P::Subpixel>

Consumes the image buffer and returns the underlying data as an owned buffer

Methods from Deref<Target = [P::Subpixel]>

fn len(&self) -> usize

Returns the number of elements in the slice.

Examples

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

fn is_empty(&self) -> bool

Returns true if the slice has a length of 0.

Examples

let a = [1, 2, 3];
assert!(!a.is_empty());

fn first(&self) -> Option<&T>

Returns the first element of the slice, or None if it is empty.

Examples

let v = [10, 40, 30];
assert_eq!(Some(&10), v.first());

let w: &[i32] = &[];
assert_eq!(None, w.first());

fn first_mut(&mut self) -> Option<&mut T>

Returns a mutable pointer to the first element of the slice, or None if it is empty.

Examples

let x = &mut [0, 1, 2];

if let Some(first) = x.first_mut() {
    *first = 5;
}
assert_eq!(x, &[5, 1, 2]);

fn split_first(&self) -> Option<(&T, &[T])>

Returns the first and all the rest of the elements of the slice, or None if it is empty.

Examples

let x = &[0, 1, 2];

if let Some((first, elements)) = x.split_first() {
    assert_eq!(first, &0);
    assert_eq!(elements, &[1, 2]);
}

fn split_first_mut(&mut self) -> Option<(&mut T, &mut [T])>

Returns the first and all the rest of the elements of the slice, or None if it is empty.

Examples

let x = &mut [0, 1, 2];

if let Some((first, elements)) = x.split_first_mut() {
    *first = 3;
    elements[0] = 4;
    elements[1] = 5;
}
assert_eq!(x, &[3, 4, 5]);

fn split_last(&self) -> Option<(&T, &[T])>

Returns the last and all the rest of the elements of the slice, or None if it is empty.

Examples

let x = &[0, 1, 2];

if let Some((last, elements)) = x.split_last() {
    assert_eq!(last, &2);
    assert_eq!(elements, &[0, 1]);
}

fn split_last_mut(&mut self) -> Option<(&mut T, &mut [T])>

Returns the last and all the rest of the elements of the slice, or None if it is empty.

Examples

let x = &mut [0, 1, 2];

if let Some((last, elements)) = x.split_last_mut() {
    *last = 3;
    elements[0] = 4;
    elements[1] = 5;
}
assert_eq!(x, &[4, 5, 3]);

fn last(&self) -> Option<&T>

Returns the last element of the slice, or None if it is empty.

Examples

let v = [10, 40, 30];
assert_eq!(Some(&30), v.last());

let w: &[i32] = &[];
assert_eq!(None, w.last());

fn last_mut(&mut self) -> Option<&mut T>

Returns a mutable pointer to the last item in the slice.

Examples

let x = &mut [0, 1, 2];

if let Some(last) = x.last_mut() {
    *last = 10;
}
assert_eq!(x, &[0, 1, 10]);

fn get<I>(&self, index: I) -> Option<&<I as SliceIndex<[T]>>::Output> where
    I: SliceIndex<[T]>, 

Returns a reference to an element or subslice depending on the type of index.

• If given a position, returns a reference to the element at that position or None if out of bounds.
• If given a range, returns the subslice corresponding to that range, or None if out of bounds.

Examples

let v = [10, 40, 30];
assert_eq!(Some(&40), v.get(1));
assert_eq!(Some(&[10, 40][..]), v.get(0..2));
assert_eq!(None, v.get(3));
assert_eq!(None, v.get(0..4));

fn get_mut<I>(
    &mut self,
    index: I
) -> Option<&mut <I as SliceIndex<[T]>>::Output> where
    I: SliceIndex<[T]>, 

Returns a mutable reference to an element or subslice depending on the type of index (see get) or None if the index is out of bounds.

Examples

let x = &mut [0, 1, 2];

if let Some(elem) = x.get_mut(1) {
    *elem = 42;
}
assert_eq!(x, &[0, 42, 2]);

unsafe fn get_unchecked<I>(&self, index: I) -> &<I as SliceIndex<[T]>>::Output where
    I: SliceIndex<[T]>, 

Returns a reference to an element or subslice, without doing bounds checking.

This is generally not recommended, use with caution! For a safe alternative see get.

Examples

let x = &[1, 2, 4];

unsafe {
    assert_eq!(x.get_unchecked(1), &2);
}

unsafe fn get_unchecked_mut<I>(
    &mut self,
    index: I
) -> &mut <I as SliceIndex<[T]>>::Output where
    I: SliceIndex<[T]>, 

Returns a mutable reference to an element or subslice, without doing bounds checking.

This is generally not recommended, use with caution! For a safe alternative see get_mut.

Examples

let x = &mut [1, 2, 4];

unsafe {
    let elem = x.get_unchecked_mut(1);
    *elem = 13;
}
assert_eq!(x, &[1, 13, 4]);

fn as_ptr(&self) -> *const T

Returns a raw pointer to the slice's buffer.

The caller must ensure that the slice outlives the pointer this function returns, or else it will end up pointing to garbage.

Modifying the container referenced by this slice may cause its buffer to be reallocated, which would also make any pointers to it invalid.

Examples

let x = &[1, 2, 4];
let x_ptr = x.as_ptr();

unsafe {
    for i in 0..x.len() {
        assert_eq!(x.get_unchecked(i), &*x_ptr.offset(i as isize));
    }
}

fn as_mut_ptr(&mut self) -> *mut T

Returns an unsafe mutable pointer to the slice's buffer.

The caller must ensure that the slice outlives the pointer this function returns, or else it will end up pointing to garbage.

Modifying the container referenced by this slice may cause its buffer to be reallocated, which would also make any pointers to it invalid.

Examples

let x = &mut [1, 2, 4];
let x_ptr = x.as_mut_ptr();

unsafe {
    for i in 0..x.len() {
        *x_ptr.offset(i as isize) += 2;
    }
}
assert_eq!(x, &[3, 4, 6]);

fn swap(&mut self, a: usize, b: usize)

Swaps two elements in the slice.

Arguments

• a - The index of the first element
• b - The index of the second element

Panics

Panics if a or b are out of bounds.

Examples

let mut v = ["a", "b", "c", "d"];
v.swap(1, 3);
assert!(v == ["a", "d", "c", "b"]);

fn reverse(&mut self)

Reverses the order of elements in the slice, in place.

Examples

let mut v = [1, 2, 3];
v.reverse();
assert!(v == [3, 2, 1]);

fn iter(&self) -> Iter<T>

Returns an iterator over the slice.

Examples

let x = &[1, 2, 4];
let mut iterator = x.iter();

assert_eq!(iterator.next(), Some(&1));
assert_eq!(iterator.next(), Some(&2));
assert_eq!(iterator.next(), Some(&4));
assert_eq!(iterator.next(), None);

fn iter_mut(&mut self) -> IterMut<T>

Returns an iterator that allows modifying each value.

Examples

let x = &mut [1, 2, 4];
for elem in x.iter_mut() {
    *elem += 2;
}
assert_eq!(x, &[3, 4, 6]);

fn windows(&self, size: usize) -> Windows<T>

Returns an iterator over all contiguous windows of length size. The windows overlap. If the slice is shorter than size, the iterator returns no values.

Panics

Panics if size is 0.

Examples

let slice = ['r', 'u', 's', 't'];
let mut iter = slice.windows(2);
assert_eq!(iter.next().unwrap(), &['r', 'u']);
assert_eq!(iter.next().unwrap(), &['u', 's']);
assert_eq!(iter.next().unwrap(), &['s', 't']);
assert!(iter.next().is_none());

If the slice is shorter than size:

let slice = ['f', 'o', 'o'];
let mut iter = slice.windows(4);
assert!(iter.next().is_none());

fn chunks(&self, size: usize) -> Chunks<T>

Returns an iterator over size elements of the slice at a time. The chunks are slices and do not overlap. If size does not divide the length of the slice, then the last chunk will not have length size.

Panics

Panics if size is 0.

Examples

let slice = ['l', 'o', 'r', 'e', 'm'];
let mut iter = slice.chunks(2);
assert_eq!(iter.next().unwrap(), &['l', 'o']);
assert_eq!(iter.next().unwrap(), &['r', 'e']);
assert_eq!(iter.next().unwrap(), &['m']);
assert!(iter.next().is_none());

fn chunks_mut(&mut self, chunk_size: usize) -> ChunksMut<T>

Returns an iterator over chunk_size elements of the slice at a time. The chunks are mutable slices, and do not overlap. If chunk_size does not divide the length of the slice, then the last chunk will not have length chunk_size.

Panics

Panics if chunk_size is 0.

Examples

let v = &mut [0, 0, 0, 0, 0];
let mut count = 1;

for chunk in v.chunks_mut(2) {
    for elem in chunk.iter_mut() {
        *elem += count;
    }
    count += 1;
}
assert_eq!(v, &[1, 1, 2, 2, 3]);

fn split_at(&self, mid: usize) -> (&[T], &[T])

Divides one slice into two at an index.

The first will contain all indices from [0, mid) (excluding the index mid itself) and the second will contain all indices from [mid, len) (excluding the index len itself).

Panics

Panics if mid > len.

Examples

let v = [1, 2, 3, 4, 5, 6];

{
   let (left, right) = v.split_at(0);
   assert!(left == []);
   assert!(right == [1, 2, 3, 4, 5, 6]);
}

{
    let (left, right) = v.split_at(2);
    assert!(left == [1, 2]);
    assert!(right == [3, 4, 5, 6]);
}

{
    let (left, right) = v.split_at(6);
    assert!(left == [1, 2, 3, 4, 5, 6]);
    assert!(right == []);
}

fn split_at_mut(&mut self, mid: usize) -> (&mut [T], &mut [T])

Divides one &mut into two at an index.

The first will contain all indices from [0, mid) (excluding the index mid itself) and the second will contain all indices from [mid, len) (excluding the index len itself).

Panics

Panics if mid > len.

Examples

let mut v = [1, 0, 3, 0, 5, 6];
// scoped to restrict the lifetime of the borrows
{
    let (left, right) = v.split_at_mut(2);
    assert!(left == [1, 0]);
    assert!(right == [3, 0, 5, 6]);
    left[1] = 2;
    right[1] = 4;
}
assert!(v == [1, 2, 3, 4, 5, 6]);

fn split<F>(&self, pred: F) -> Split<T, F> where
    F: FnMut(&T) -> bool, 

Returns an iterator over subslices separated by elements that match pred. The matched element is not contained in the subslices.

Examples

let slice = [10, 40, 33, 20];
let mut iter = slice.split(|num| num % 3 == 0);

assert_eq!(iter.next().unwrap(), &[10, 40]);
assert_eq!(iter.next().unwrap(), &[20]);
assert!(iter.next().is_none());

If the first element is matched, an empty slice will be the first item returned by the iterator. Similarly, if the last element in the slice is matched, an empty slice will be the last item returned by the iterator:

let slice = [10, 40, 33];
let mut iter = slice.split(|num| num % 3 == 0);

assert_eq!(iter.next().unwrap(), &[10, 40]);
assert_eq!(iter.next().unwrap(), &[]);
assert!(iter.next().is_none());

If two matched elements are directly adjacent, an empty slice will be present between them:

let slice = [10, 6, 33, 20];
let mut iter = slice.split(|num| num % 3 == 0);

assert_eq!(iter.next().unwrap(), &[10]);
assert_eq!(iter.next().unwrap(), &[]);
assert_eq!(iter.next().unwrap(), &[20]);
assert!(iter.next().is_none());

fn split_mut<F>(&mut self, pred: F) -> SplitMut<T, F> where
    F: FnMut(&T) -> bool, 

Returns an iterator over mutable subslices separated by elements that match pred. The matched element is not contained in the subslices.

Examples

let mut v = [10, 40, 30, 20, 60, 50];

for group in v.split_mut(|num| *num % 3 == 0) {
    group[0] = 1;
}
assert_eq!(v, [1, 40, 30, 1, 60, 1]);

fn rsplit<F>(&self, pred: F) -> RSplit<T, F> where
    F: FnMut(&T) -> bool, 

🔬 This is a nightly-only experimental API. (slice_rsplit)

Returns an iterator over subslices separated by elements that match pred, starting at the end of the slice and working backwards. The matched element is not contained in the subslices.

Examples

#![feature(slice_rsplit)]

let slice = [11, 22, 33, 0, 44, 55];
let mut iter = slice.rsplit(|num| *num == 0);

assert_eq!(iter.next().unwrap(), &[44, 55]);
assert_eq!(iter.next().unwrap(), &[11, 22, 33]);
assert_eq!(iter.next(), None);

As with split(), if the first or last element is matched, an empty slice will be the first (or last) item returned by the iterator.

#![feature(slice_rsplit)]

let v = &[0, 1, 1, 2, 3, 5, 8];
let mut it = v.rsplit(|n| *n % 2 == 0);
assert_eq!(it.next().unwrap(), &[]);
assert_eq!(it.next().unwrap(), &[3, 5]);
assert_eq!(it.next().unwrap(), &[1, 1]);
assert_eq!(it.next().unwrap(), &[]);
assert_eq!(it.next(), None);

fn rsplit_mut<F>(&mut self, pred: F) -> RSplitMut<T, F> where
    F: FnMut(&T) -> bool, 

🔬 This is a nightly-only experimental API. (slice_rsplit)

Returns an iterator over mutable subslices separated by elements that match pred, starting at the end of the slice and working backwards. The matched element is not contained in the subslices.

Examples

#![feature(slice_rsplit)]

let mut v = [100, 400, 300, 200, 600, 500];

let mut count = 0;
for group in v.rsplit_mut(|num| *num % 3 == 0) {
    count += 1;
    group[0] = count;
}
assert_eq!(v, [3, 400, 300, 2, 600, 1]);

fn splitn<F>(&self, n: usize, pred: F) -> SplitN<T, F> where
    F: FnMut(&T) -> bool, 

Returns an iterator over subslices separated by elements that match pred, limited to returning at most n items. The matched element is not contained in the subslices.

The last element returned, if any, will contain the remainder of the slice.

Examples

Print the slice split once by numbers divisible by 3 (i.e. [10, 40], [20, 60, 50]):

let v = [10, 40, 30, 20, 60, 50];

for group in v.splitn(2, |num| *num % 3 == 0) {
    println!("{:?}", group);
}

fn splitn_mut<F>(&mut self, n: usize, pred: F) -> SplitNMut<T, F> where
    F: FnMut(&T) -> bool, 

Returns an iterator over subslices separated by elements that match pred, limited to returning at most n items. The matched element is not contained in the subslices.

The last element returned, if any, will contain the remainder of the slice.

Examples

let mut v = [10, 40, 30, 20, 60, 50];

for group in v.splitn_mut(2, |num| *num % 3 == 0) {
    group[0] = 1;
}
assert_eq!(v, [1, 40, 30, 1, 60, 50]);

fn rsplitn<F>(&self, n: usize, pred: F) -> RSplitN<T, F> where
    F: FnMut(&T) -> bool, 

Returns an iterator over subslices separated by elements that match pred limited to returning at most n items. This starts at the end of the slice and works backwards. The matched element is not contained in the subslices.

The last element returned, if any, will contain the remainder of the slice.

Examples

Print the slice split once, starting from the end, by numbers divisible by 3 (i.e. [50], [10, 40, 30, 20]):

let v = [10, 40, 30, 20, 60, 50];

for group in v.rsplitn(2, |num| *num % 3 == 0) {
    println!("{:?}", group);
}

fn rsplitn_mut<F>(&mut self, n: usize, pred: F) -> RSplitNMut<T, F> where
    F: FnMut(&T) -> bool, 

Returns an iterator over subslices separated by elements that match pred limited to returning at most n items. This starts at the end of the slice and works backwards. The matched element is not contained in the subslices.

The last element returned, if any, will contain the remainder of the slice.

Examples

let mut s = [10, 40, 30, 20, 60, 50];

for group in s.rsplitn_mut(2, |num| *num % 3 == 0) {
    group[0] = 1;
}
assert_eq!(s, [1, 40, 30, 20, 60, 1]);

fn contains(&self, x: &T) -> bool where
    T: PartialEq<T>, 

Returns true if the slice contains an element with the given value.

Examples

let v = [10, 40, 30];
assert!(v.contains(&30));
assert!(!v.contains(&50));

fn starts_with(&self, needle: &[T]) -> bool where
    T: PartialEq<T>, 

Returns true if needle is a prefix of the slice.

Examples

let v = [10, 40, 30];
assert!(v.starts_with(&[10]));
assert!(v.starts_with(&[10, 40]));
assert!(!v.starts_with(&[50]));
assert!(!v.starts_with(&[10, 50]));

Always returns true if needle is an empty slice:

let v = &[10, 40, 30];
assert!(v.starts_with(&[]));
let v: &[u8] = &[];
assert!(v.starts_with(&[]));

fn ends_with(&self, needle: &[T]) -> bool where
    T: PartialEq<T>, 

Returns true if needle is a suffix of the slice.

Examples

let v = [10, 40, 30];
assert!(v.ends_with(&[30]));
assert!(v.ends_with(&[40, 30]));
assert!(!v.ends_with(&[50]));
assert!(!v.ends_with(&[50, 30]));

Always returns true if needle is an empty slice:

let v = &[10, 40, 30];
assert!(v.ends_with(&[]));
let v: &[u8] = &[];
assert!(v.ends_with(&[]));

fn binary_search(&self, x: &T) -> Result<usize, usize> where
    T: Ord, 

Binary searches this sorted slice for a given element.

If the value is found then Ok is returned, containing the index of the matching element; if the value is not found then Err is returned, containing the index where a matching element could be inserted while maintaining sorted order.

Examples

Looks up a series of four elements. The first is found, with a uniquely determined position; the second and third are not found; the fourth could match any position in [1, 4].

let s = [0, 1, 1, 1, 1, 2, 3, 5, 8, 13, 21, 34, 55];

assert_eq!(s.binary_search(&13),  Ok(9));
assert_eq!(s.binary_search(&4),   Err(7));
assert_eq!(s.binary_search(&100), Err(13));
let r = s.binary_search(&1);
assert!(match r { Ok(1...4) => true, _ => false, });

fn binary_search_by<'a, F>(&'a self, f: F) -> Result<usize, usize> where
    F: FnMut(&'a T) -> Ordering, 

Binary searches this sorted slice with a comparator function.

The comparator function should implement an order consistent with the sort order of the underlying slice, returning an order code that indicates whether its argument is Less, Equal or Greater the desired target.

If a matching value is found then returns Ok, containing the index for the matched element; if no match is found then Err is returned, containing the index where a matching element could be inserted while maintaining sorted order.

Examples

Looks up a series of four elements. The first is found, with a uniquely determined position; the second and third are not found; the fourth could match any position in [1, 4].

let s = [0, 1, 1, 1, 1, 2, 3, 5, 8, 13, 21, 34, 55];

let seek = 13;
assert_eq!(s.binary_search_by(|probe| probe.cmp(&seek)), Ok(9));
let seek = 4;
assert_eq!(s.binary_search_by(|probe| probe.cmp(&seek)), Err(7));
let seek = 100;
assert_eq!(s.binary_search_by(|probe| probe.cmp(&seek)), Err(13));
let seek = 1;
let r = s.binary_search_by(|probe| probe.cmp(&seek));
assert!(match r { Ok(1...4) => true, _ => false, });

fn binary_search_by_key<'a, B, F>(&'a self, b: &B, f: F) -> Result<usize, usize> where
    B: Ord,
    F: FnMut(&'a T) -> B, 

Binary searches this sorted slice with a key extraction function.

Assumes that the slice is sorted by the key, for instance with sort_by_key using the same key extraction function.

If a matching value is found then returns Ok, containing the index for the matched element; if no match is found then Err is returned, containing the index where a matching element could be inserted while maintaining sorted order.

Examples

Looks up a series of four elements in a slice of pairs sorted by their second elements. The first is found, with a uniquely determined position; the second and third are not found; the fourth could match any position in [1, 4].

let s = [(0, 0), (2, 1), (4, 1), (5, 1), (3, 1),
         (1, 2), (2, 3), (4, 5), (5, 8), (3, 13),
         (1, 21), (2, 34), (4, 55)];

assert_eq!(s.binary_search_by_key(&13, |&(a,b)| b),  Ok(9));
assert_eq!(s.binary_search_by_key(&4, |&(a,b)| b),   Err(7));
assert_eq!(s.binary_search_by_key(&100, |&(a,b)| b), Err(13));
let r = s.binary_search_by_key(&1, |&(a,b)| b);
assert!(match r { Ok(1...4) => true, _ => false, });

fn sort(&mut self) where
    T: Ord, 

Sorts the slice.

This sort is stable (i.e. does not reorder equal elements) and O(n log n) worst-case.

When applicable, unstable sorting is preferred because it is generally faster than stable sorting and it doesn't allocate auxiliary memory. See sort_unstable.

Current implementation

The current algorithm is an adaptive, iterative merge sort inspired by timsort. It is designed to be very fast in cases where the slice is nearly sorted, or consists of two or more sorted sequences concatenated one after another.

Also, it allocates temporary storage half the size of self, but for short slices a non-allocating insertion sort is used instead.

Examples

let mut v = [-5, 4, 1, -3, 2];

v.sort();
assert!(v == [-5, -3, 1, 2, 4]);

fn sort_by<F>(&mut self, compare: F) where
    F: FnMut(&T, &T) -> Ordering, 

Sorts the slice with a comparator function.

This sort is stable (i.e. does not reorder equal elements) and O(n log n) worst-case.

When applicable, unstable sorting is preferred because it is generally faster than stable sorting and it doesn't allocate auxiliary memory. See sort_unstable_by.

Current implementation

The current algorithm is an adaptive, iterative merge sort inspired by timsort. It is designed to be very fast in cases where the slice is nearly sorted, or consists of two or more sorted sequences concatenated one after another.

Also, it allocates temporary storage half the size of self, but for short slices a non-allocating insertion sort is used instead.

Examples

let mut v = [5, 4, 1, 3, 2];
v.sort_by(|a, b| a.cmp(b));
assert!(v == [1, 2, 3, 4, 5]);

// reverse sorting
v.sort_by(|a, b| b.cmp(a));
assert!(v == [5, 4, 3, 2, 1]);

fn sort_by_key<B, F>(&mut self, f: F) where
    B: Ord,
    F: FnMut(&T) -> B, 

Sorts the slice with a key extraction function.

This sort is stable (i.e. does not reorder equal elements) and O(n log n) worst-case.

When applicable, unstable sorting is preferred because it is generally faster than stable sorting and it doesn't allocate auxiliary memory. See sort_unstable_by_key.

Current implementation

The current algorithm is an adaptive, iterative merge sort inspired by timsort. It is designed to be very fast in cases where the slice is nearly sorted, or consists of two or more sorted sequences concatenated one after another.

Also, it allocates temporary storage half the size of self, but for short slices a non-allocating insertion sort is used instead.

Examples

let mut v = [-5i32, 4, 1, -3, 2];

v.sort_by_key(|k| k.abs());
assert!(v == [1, 2, -3, 4, -5]);

fn sort_unstable(&mut self) where
    T: Ord, 

Sorts the slice, but may not preserve the order of equal elements.

This sort is unstable (i.e. may reorder equal elements), in-place (i.e. does not allocate), and O(n log n) worst-case.

Current implementation

The current algorithm is based on pattern-defeating quicksort by Orson Peters, which combines the fast average case of randomized quicksort with the fast worst case of heapsort, while achieving linear time on slices with certain patterns. It uses some randomization to avoid degenerate cases, but with a fixed seed to always provide deterministic behavior.

It is typically faster than stable sorting, except in a few special cases, e.g. when the slice consists of several concatenated sorted sequences.

Examples

let mut v = [-5, 4, 1, -3, 2];

v.sort_unstable();
assert!(v == [-5, -3, 1, 2, 4]);

fn sort_unstable_by<F>(&mut self, compare: F) where
    F: FnMut(&T, &T) -> Ordering, 

Sorts the slice with a comparator function, but may not preserve the order of equal elements.

This sort is unstable (i.e. may reorder equal elements), in-place (i.e. does not allocate), and O(n log n) worst-case.

Current implementation

The current algorithm is based on pattern-defeating quicksort by Orson Peters, which combines the fast average case of randomized quicksort with the fast worst case of heapsort, while achieving linear time on slices with certain patterns. It uses some randomization to avoid degenerate cases, but with a fixed seed to always provide deterministic behavior.

It is typically faster than stable sorting, except in a few special cases, e.g. when the slice consists of several concatenated sorted sequences.

Examples

let mut v = [5, 4, 1, 3, 2];
v.sort_unstable_by(|a, b| a.cmp(b));
assert!(v == [1, 2, 3, 4, 5]);

// reverse sorting
v.sort_unstable_by(|a, b| b.cmp(a));
assert!(v == [5, 4, 3, 2, 1]);

fn sort_unstable_by_key<B, F>(&mut self, f: F) where
    B: Ord,
    F: FnMut(&T) -> B, 

Sorts the slice with a key extraction function, but may not preserve the order of equal elements.

This sort is unstable (i.e. may reorder equal elements), in-place (i.e. does not allocate), and O(n log n) worst-case.

Current implementation

The current algorithm is based on pattern-defeating quicksort by Orson Peters, which combines the fast average case of randomized quicksort with the fast worst case of heapsort, while achieving linear time on slices with certain patterns. It uses some randomization to avoid degenerate cases, but with a fixed seed to always provide deterministic behavior.

It is typically faster than stable sorting, except in a few special cases, e.g. when the slice consists of several concatenated sorted sequences.

Examples

let mut v = [-5i32, 4, 1, -3, 2];

v.sort_unstable_by_key(|k| k.abs());
assert!(v == [1, 2, -3, 4, -5]);

fn rotate(&mut self, mid: usize)

🔬 This is a nightly-only experimental API. (slice_rotate)

Permutes the slice in-place such that self[mid..] moves to the beginning of the slice while self[..mid] moves to the end of the slice. Equivalently, rotates the slice mid places to the left or k = self.len() - mid places to the right.

This is a "k-rotation", a permutation in which item i moves to position i + k, modulo the length of the slice. See Elements of Programming §10.4.

Rotation by mid and rotation by k are inverse operations.

Panics

This function will panic if mid is greater than the length of the slice. (Note that mid == self.len() does not panic; it's a nop rotation with k == 0, the inverse of a rotation with mid == 0.)

Complexity

Takes linear (in self.len()) time.

Examples

#![feature(slice_rotate)]

let mut a = [1, 2, 3, 4, 5, 6, 7];
let mid = 2;
a.rotate(mid);
assert_eq!(&a, &[3, 4, 5, 6, 7, 1, 2]);
let k = a.len() - mid;
a.rotate(k);
assert_eq!(&a, &[1, 2, 3, 4, 5, 6, 7]);

use std::ops::Range;
fn slide<T>(slice: &mut [T], range: Range<usize>, to: usize) {
    if to < range.start {
        slice[to..range.end].rotate(range.start-to);
    } else if to > range.end {
        slice[range.start..to].rotate(range.end-range.start);
    }
}
let mut v: Vec<_> = (0..10).collect();
slide(&mut v, 1..4, 7);
assert_eq!(&v, &[0, 4, 5, 6, 1, 2, 3, 7, 8, 9]);
slide(&mut v, 6..8, 1);
assert_eq!(&v, &[0, 3, 7, 4, 5, 6, 1, 2, 8, 9]);

fn clone_from_slice(&mut self, src: &[T]) where
    T: Clone, 

Copies the elements from src into self.

The length of src must be the same as self.

If src implements Copy, it can be more performant to use copy_from_slice.

Panics

This function will panic if the two slices have different lengths.

Examples

let mut dst = [0, 0, 0];
let src = [1, 2, 3];

dst.clone_from_slice(&src);
assert!(dst == [1, 2, 3]);

fn copy_from_slice(&mut self, src: &[T]) where
    T: Copy, 

Copies all elements from src into self, using a memcpy.

The length of src must be the same as self.

If src does not implement Copy, use clone_from_slice.

Panics

This function will panic if the two slices have different lengths.

Examples

let mut dst = [0, 0, 0];
let src = [1, 2, 3];

dst.copy_from_slice(&src);
assert_eq!(src, dst);

fn swap_with_slice(&mut self, src: &mut [T])

🔬 This is a nightly-only experimental API. (swap_with_slice)

Swaps all elements in self with those in src.

The length of src must be the same as self.

Panics

This function will panic if the two slices have different lengths.

Example

#![feature(swap_with_slice)]

let mut src = [1, 2, 3];
let mut dst = [7, 8, 9];

src.swap_with_slice(&mut dst);
assert_eq!(src, [7, 8, 9]);
assert_eq!(dst, [1, 2, 3]);

fn to_vec(&self) -> Vec<T> where
    T: Clone, 

Copies self into a new Vec.

Examples

let s = [10, 40, 30];
let x = s.to_vec();
// Here, `s` and `x` can be modified independently.

Trait Implementations

impl<P: Debug + Pixel, Container: Debug> Debug for ImageBuffer<P, Container>

fn fmt(&self, __arg_0: &mut Formatter) -> Result

Formats the value using the given formatter.

impl<P, Container> Deref for ImageBuffer<P, Container> where
    P: Pixel + 'static,
    P::Subpixel: 'static,
    Container: Deref<Target = [P::Subpixel]>, 

type Target = [P::Subpixel]

The resulting type after dereferencing.

fn deref(&self) -> &Self::Target

Dereferences the value.

impl<P, Container> DerefMut for ImageBuffer<P, Container> where
    P: Pixel + 'static,
    P::Subpixel: 'static,
    Container: Deref<Target = [P::Subpixel]> + DerefMut, 

fn deref_mut(&mut self) -> &mut Self::Target

Mutably dereferences the value.

impl<P, Container> Index<(u32, u32)> for ImageBuffer<P, Container> where
    P: Pixel + 'static,
    P::Subpixel: 'static,
    Container: Deref<Target = [P::Subpixel]>, 

type Output = P

The returned type after indexing.

fn index(&self, (x, y): (u32, u32)) -> &P

Performs the indexing (container[index]) operation.

impl<P, Container> IndexMut<(u32, u32)> for ImageBuffer<P, Container> where
    P: Pixel + 'static,
    P::Subpixel: 'static,
    Container: Deref<Target = [P::Subpixel]> + DerefMut, 

fn index_mut(&mut self, (x, y): (u32, u32)) -> &mut P

Performs the mutable indexing (container[index]) operation.

impl<P, Container> Clone for ImageBuffer<P, Container> where
    P: Pixel,
    Container: Deref<Target = [P::Subpixel]> + Clone, 

fn clone(&self) -> ImageBuffer<P, Container>

Returns a copy of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl<P, Container> GenericImage for ImageBuffer<P, Container> where
    P: Pixel + 'static,
    Container: Deref<Target = [P::Subpixel]> + DerefMut,
    P::Subpixel: 'static, 

type Pixel = P

The type of pixel.

fn dimensions(&self) -> (u32, u32)

The width and height of this image.

fn bounds(&self) -> (u32, u32, u32, u32)

The bounding rectangle of this image.

fn get_pixel(&self, x: u32, y: u32) -> P

Returns the pixel located at (x, y)

fn get_pixel_mut(&mut self, x: u32, y: u32) -> &mut P

Puts a pixel at location (x, y)

unsafe fn unsafe_get_pixel(&self, x: u32, y: u32) -> P

Returns the pixel located at (x, y), ignoring bounds checking.

fn put_pixel(&mut self, x: u32, y: u32, pixel: P)

Put a pixel at location (x, y)

unsafe fn unsafe_put_pixel(&mut self, x: u32, y: u32, pixel: P)

Puts a pixel at location (x, y), ignoring bounds checking.

fn blend_pixel(&mut self, x: u32, y: u32, p: P)

Put a pixel at location (x, y), taking into account alpha channels

DEPRECATED: This method will be removed. Blend the pixel directly instead.

fn width(&self) -> u32

The width of this image.

fn height(&self) -> u32

The height of this image.

fn in_bounds(&self, x: u32, y: u32) -> bool

Returns true if this x, y coordinate is contained inside the image.

fn pixels(&self) -> Pixels<Self>

Returns an Iterator over the pixels of this image. The iterator yields the coordinates of each pixel along with their value

fn pixels_mut(&mut self) -> MutPixels<Self>

Returns an Iterator over mutable pixels of this image. The iterator yields the coordinates of each pixel along with a mutable reference to them.

fn copy_from<O>(&mut self, other: &O, x: u32, y: u32) -> bool where
    O: GenericImage<Pixel = Self::Pixel>, 

Copies all of the pixels from another image into this image.

fn sub_image(
    &mut self,
    x: u32,
    y: u32,
    width: u32,
    height: u32
) -> SubImage<Self> where
    Self: 'static,
    <Self::Pixel as Pixel>::Subpixel: 'static,
    Self::Pixel: 'static, 

Returns a subimage that is a view into this image.

impl<'a, 'b, Container, FromType: Pixel + 'static, ToType: Pixel + 'static> ConvertBuffer<ImageBuffer<ToType, Vec<ToType::Subpixel>>> for ImageBuffer<FromType, Container> where
    Container: Deref<Target = [FromType::Subpixel]>,
    ToType: FromColor<FromType>,
    FromType::Subpixel: 'static,
    ToType::Subpixel: 'static, 

fn convert(&self) -> ImageBuffer<ToType, Vec<ToType::Subpixel>>

Converts self to a buffer of type T