Struct Polygon 

pub struct Polygon<T: Coord = i32, S: AsRef<[Point<T>]> = Vec<Point<T>>> { /* private fields */ }

Polygon shape defined by a list of vertices.

Depending on the storage type S, a Polygon can own its vertices (eg. Vec<Point>) or they can borrowed (eg. &[Point]).

Implementations

impl<T: Coord, S: AsRef<[Point<T>]>> Polygon<T, S>

pub fn new(points: S) -> Polygon<T, S>

Create a view of a set of points as a polygon.

pub fn borrow(&self) -> Polygon<T, &[Point<T>]>

Return a polygon which borrows its points from this polygon.

pub fn edges(&self) -> impl Iterator<Item = Line<T>> + '_

Return an iterator over the edges of this polygon.

pub fn vertices(&self) -> &[Point<T>]

Return a slice of the endpoints of the polygon’s edges.

pub fn to_owned(&self) -> Polygon<T>

Return a clone of this polygon which owns its vertices.

impl<S: AsRef<[Point]>> Polygon<i32, S>

pub fn fill_iter(&self) -> FillIter

Return an iterator over coordinates of pixels that fill the polygon.

Polygon filling treats the polygon’s vertices as being located at the center of pixels with the corresponding coordinates. Pixels are deemed inside the polygon if a ray from -infinity to the pixel’s center crosses an odd number of polygon edges, aka. the even-odd rule ¹. Pixel centers which lie exactly on a polygon edge are treated as inside the polygon for top/left edges and outside the polygon for bottom/right edges. This follows conventions in various graphics libraries (eg. ²).

This treatment of polygon vertices differs from graphics libraries like Skia or Qt which use float coordinates for paths. In those libraries polygon filling is still based on the relationship between polygon edges and pixel centers, but integer polygon vertex coordinates refer to the corners of pixels.

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1. https://en.wikipedia.org/wiki/Even–odd_rule ↩

2. https://learn.microsoft.com/en-us/windows/win32/direct3d11/d3d10-graphics-programming-guide-rasterizer-stage-rules#triangle-rasterization-rules-without-multisampling ↩

pub fn contains_pixel(&self, p: Point) -> bool

Return true if the pixel with coordinates p lies inside the polygon.

The intent of this function is to align with Polygon::fill_iter such that polygon.contains_pixel(p) is equivalent to polygon.fill_iter().any(|fp| fp == p) but faster because it doesn’t iterate over every pixel inside the polygon. See Polygon::fill_iter for notes on how the inside/outisde status of a pixel is determined.

pub fn is_simple(&self) -> bool

Return true if this polygon has no self-intersections and no holes.

Trait Implementations

impl<S: AsRef<[Point<f32>]>> BoundingRect for Polygon<f32, S>

type Coord = f32

Coordinate type of bounding rect.

fn bounding_rect(&self) -> Rect<f32>

Return the smallest axis-aligned bounding rect which contains this shape.

impl<S: AsRef<[Point<i32>]>> BoundingRect for Polygon<i32, S>

type Coord = i32

Coordinate type of bounding rect.

fn bounding_rect(&self) -> Rect<i32>

Return the smallest axis-aligned bounding rect which contains this shape.

impl<T: Clone + Coord, S: Clone + AsRef<[Point<T>]>> Clone for Polygon<T, S>

fn clone(&self) -> Polygon<T, S>

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl<T: Debug + Coord, S: Debug + AsRef<[Point<T>]>> Debug for Polygon<T, S>

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl<T: Copy + Coord, S: Copy + AsRef<[Point<T>]>> Copy for Polygon<T, S>