Struct quicksilver::geom::Transform

pub struct Transform(_);

A 2D transformation represented by a matrix

Transforms can be composed together through matrix multiplication, and are applied to Vectors through multiplication, meaning the notation used is the '*' operator. A property of matrix multiplication is that for some matrices A, B, C and vector V is

Transform = A * B * C
Transform * V = A * (B * (C * V))

This property allows encoding multiple transformations in a single matrix. A transformation that involves rotating a shape 30 degrees and then moving it six units up could be written as

use quicksilver::geom::{Transform, Vector};
let transform = Transform::rotate(30) * Transform::translate(Vector::new(0, -6));

and then applied to a Vector

transform * Vector::new(5, 5)

Methods

impl Transform

pub fn identity() -> Transform

Create an identity transformation

pub fn rotate<T: Scalar>(angle: T) -> Transform

Create a rotation transformation

pub fn translate(vec: Vector) -> Transform

Create a translation transformation

pub fn scale(vec: Vector) -> Transform

Create a scale transformation

pub fn into_matrix(self) -> Matrix3<f32>

Convert the Transform into an nalgebra Matrix3

pub fn inverse(&self) -> Transform

Find the inverse of a Transform

A transform's inverse will cancel it out when multplied with it, as seen below:

let transform = Transform::translate(Vector::new(4, 5));
let inverse = transform.inverse();
let vector = Vector::new(10, 10);
assert_eq!(vector, transform * inverse * vector);
assert_eq!(vector, inverse * transform * vector);

Trait Implementations

impl Clone for Transform

fn clone(&self) -> Transform

Returns a copy of the value.

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

Performs copy-assignment from source.

impl Copy for Transform

impl Debug for Transform

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

Formats the value using the given formatter.

impl Mul<Transform> for Transform

Concat two transforms A and B such that A * B * v = A * (B * v)

type Output = Transform

The resulting type after applying the * operator.

fn mul(self, other: Transform) -> Transform

Performs the * operation.

impl Mul<Vector> for Transform

Transform a vector

type Output = Vector

The resulting type after applying the * operator.

fn mul(self, other: Vector) -> Vector

Performs the * operation.

impl<T: Scalar> Mul<T> for Transform

Scale all of the internal values of the Transform matrix

Note this will NOT scale vectors multiplied by this transform, and generally you shouldn't need to use this.

type Output = Transform

The resulting type after applying the * operator.

fn mul(self, other: T) -> Transform

Performs the * operation.

impl Display for Transform

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

Formats the value using the given formatter.

impl Default for Transform

fn default() -> Transform

Returns the "default value" for a type.

impl PartialEq for Transform

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

This method tests for self and other values to be equal, and is used by ==.

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

This method tests for !=.

impl Eq for Transform

impl From<Matrix3<f32>> for Transform

fn from(other: Matrix3<f32>) -> Transform

Performs the conversion.