Struct TransformationMatrix 

#[repr(C)]
pub struct TransformationMatrix {
    pub rotation_scale: [[f32; 2]; 2],
    pub translation: [f32; 2],
}

A 2D affine transform in scaled pixels: a 2x2 linear part and a translation.

Sprites carry one in MonochromeSprite::transformation and SubpixelSprite::transformation. Start from TransformationMatrix::unit and chain calls to build a transform. When you chain calls, the transform from the last call is applied to a point first.

Examples

let moved = TransformationMatrix::unit().translate(point(ScaledPixels(10.), ScaledPixels(5.)));
assert_eq!(moved.apply(point(px(1.), px(2.))), point(px(11.), px(7.)));

let scaled = TransformationMatrix::unit().scale(size(2., 3.));
assert_eq!(scaled.apply(point(px(1.), px(1.))), point(px(2.), px(3.)));

// The translation is applied first, then the scale.
let chained = TransformationMatrix::unit()
    .scale(size(2., 3.))
    .translate(point(ScaledPixels(10.), ScaledPixels(5.)));
assert_eq!(chained.apply(point(px(1.), px(1.))), point(px(22.), px(18.)));

Fields

rotation_scale: [[f32; 2]; 2]

2x2 matrix containing rotation and scale, stored row-major

translation: [f32; 2]

translation vector

Implementations

impl TransformationMatrix

pub fn unit() -> Self

Returns the identity transform, which leaves points unchanged.

pub fn translate(self, point: Point<ScaledPixels>) -> Self

Returns this transform combined with a translation by point. The translation is applied to points before this transform.

pub fn rotate(self, angle: Radians) -> Self

Returns this transform combined with a clockwise rotation by angle around the origin. Clockwise is on screen, where the y axis points down.

pub fn scale(self, size: Size<f32>) -> Self

Returns this transform combined with a scale by size around the origin.

pub fn compose(self, other: TransformationMatrix) -> TransformationMatrix

Returns self combined with other, so that other is applied to points first. This is the matrix product self * other.

pub fn apply(&self, point: Point<Pixels>) -> Point<Pixels>

Returns point transformed by this matrix.

Trait Implementations

impl Clone for TransformationMatrix

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 TransformationMatrix

impl Debug for TransformationMatrix

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

Formats the value using the given formatter.

impl Default for TransformationMatrix

fn default() -> Self

Returns the “default value” for a type.

impl Eq for TransformationMatrix

impl PartialEq for TransformationMatrix

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

Equality operator ==.

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

Inequality operator !=.

impl StructuralPartialEq for TransformationMatrix