Struct ProjectiveTransform 

pub struct ProjectiveTransform { /* private fields */ }

A projective mapping of a two-dimensional coordinate plane.

Implementations

impl ProjectiveTransform

pub const fn identity() -> Self

Leaves positions unchanged.

pub fn translation(tx: f32, ty: f32) -> Self

Translates positions by the supplied logical-pixel offsets.

pub fn uniform_scale(scale: f32) -> Self

Uniform scale about the origin (device-scale root transform: render graphs stay in logical dp; density applies at execution).

pub fn from_rect_to_quad(rect: Rect, quad: [[f32; 2]; 4]) -> Self

Maps a rectangle to corners ordered top-left, top-right, bottom-left, bottom-right, with the whole rectangle in front of the eye.

pub const fn from_rows(matrix: [[f32; 3]; 3]) -> Self

The transform of a row-major homogeneous matrix, kept as it is: its bottom row gives each point’s w, which NEAR_W cuts.

pub fn from_homogeneous(matrix: [[f32; 3]; 3]) -> Self

The transform a homogeneous matrix describes, scaled so its last entry is one or minus one wherever that entry is not zero: its other entries then read as the scale, turn, translation and perspective they are. The scale is positive, so every point keeps the side of the eye its homogeneous w puts it on.

pub fn then(self, next: Self) -> Self

Returns the composed transform that applies self first and next second.

pub fn inverse(self) -> Option<Self>

Maps destination coordinates back to the source, unless the matrix is singular.

pub fn matrix(self) -> [[f32; 3]; 3]

Returns the row-major homogeneous matrix.

pub fn map_point(&self, point: Point) -> Point

Maps a position into destination coordinates.

pub fn map_rect(&self, rect: Rect) -> [[f32; 2]; 4]

Maps a rectangle’s top-left, top-right, bottom-left and bottom-right corners.

pub fn in_front(&self, point: Point) -> bool

Whether point lies in front of the eye of the transform’s perspective, so that it maps to a position: its homogeneous w is at least NEAR_W. Always true without perspective.

pub fn rect_in_front(&self, rect: Rect) -> bool

Whether all of rect lies in front of the eye.

pub fn map_point_in_front(&self, point: Point) -> Option<Point>

Maps point through this transform, the inverse of a perspective, back onto the plane the perspective shows; None when the eye’s ray through point meets the plane behind the eye or nearer than NEAR_W. The perspective’s own w at the mapped point is one over this transform’s w at point.

pub fn front_polygon(&self, rect: Rect) -> FrontPolygon

Maps the part of rect in front of the eye: the rectangle cut where its homogeneous w falls below NEAR_W, corners in order top-left, top-right, bottom-right, bottom-left with the cut’s corners between.

pub fn bounds_for_rect(&self, rect: Rect) -> Rect

Returns the axis-aligned bounds of the transformed rectangle’s part in front of the eye; empty when no part is.

Trait Implementations

impl Clone for ProjectiveTransform

fn clone(&self) -> Self

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Copy for ProjectiveTransform

impl Debug for ProjectiveTransform

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

Formats the value using the given formatter.

impl Default for ProjectiveTransform

fn default() -> Self

Returns the “default value” for a type.

impl PartialEq for ProjectiveTransform

fn eq(&self, other: &Self) -> bool

Equality operator ==.

fn ne(&self, other: &Rhs) -> bool

Inequality operator !=.