[kaka/rust-sdl-test.git] / src / common.rs

use std::ops::{Add, AddAssign, Sub, SubAssign, Mul, MulAssign, Div, DivAssign, Neg};

#[macro_export]
macro_rules! point {
    ( $x:expr, $y:expr ) => {
        Point2D { x: $x, y: $y }
    };
}

#[derive(Debug, Default, Copy, Clone, PartialEq)]
pub struct Point2D<T> {
    pub x: T,
    pub y: T,
}

impl Point2D<f64> {
    pub fn length(&self) -> f64 {
        ((self.x * self.x) + (self.y * self.y)).sqrt()
    }

    pub fn normalized(&self) -> Self {
	let l = self.length();
	Self {
	    x: self.x / l,
	    y: self.y / l,
	}
    }

    pub fn to_radians(&self) -> Radians {
	Radians(self.y.atan2(self.x))
    }

    pub fn to_degrees(&self) -> Degrees {
	self.to_radians().to_degrees()
    }

    pub fn to_i32(self) -> Point2D<i32> {
	Point2D {
	    x: self.x as i32,
	    y: self.y as i32,
	}
    }
}

macro_rules! point_op {
    ($op:tt, $trait:ident($fn:ident), $trait_assign:ident($fn_assign:ident), $rhs:ident = $Rhs:ty => $x:expr, $y:expr) => {
        impl<T: $trait<Output = T>> $trait<$Rhs> for Point2D<T> {
            type Output = Self;

            fn $fn(self, $rhs: $Rhs) -> Self {
                Self {
                    x: self.x $op $x,
                    y: self.y $op $y,
                }
            }
        }

        impl<T: $trait<Output = T> + Copy> $trait_assign<$Rhs> for Point2D<T> {
            fn $fn_assign(&mut self, $rhs: $Rhs) {
                *self = Self {
                    x: self.x $op $x,
                    y: self.y $op $y,
                }
            }
        }
    }
}

point_op!(+, Add(add), AddAssign(add_assign), rhs = Point2D<T> => rhs.x, rhs.y);
point_op!(-, Sub(sub), SubAssign(sub_assign), rhs = Point2D<T> => rhs.x, rhs.y);
point_op!(*, Mul(mul), MulAssign(mul_assign), rhs = Point2D<T> => rhs.x, rhs.y);
point_op!(/, Div(div), DivAssign(div_assign), rhs = Point2D<T> => rhs.x, rhs.y);
point_op!(+, Add(add), AddAssign(add_assign), rhs = (T, T) => rhs.0, rhs.1);
point_op!(-, Sub(sub), SubAssign(sub_assign), rhs = (T, T) => rhs.0, rhs.1);
point_op!(*, Mul(mul), MulAssign(mul_assign), rhs = (T, T) => rhs.0, rhs.1);
point_op!(/, Div(div), DivAssign(div_assign), rhs = (T, T) => rhs.0, rhs.1);

////////// multiply point with scalar //////////////////////////////////////////
impl<T: Mul<Output = T> + Copy> Mul<T> for Point2D<T> {
    type Output = Self;

    fn mul(self, rhs: T) -> Self {
	Self {
	    x: self.x * rhs,
	    y: self.y * rhs,
	}
    }
}

impl<T: Mul<Output = T> + Copy> MulAssign<T> for Point2D<T> {
    fn mul_assign(&mut self, rhs: T) {
	*self = Self {
	    x: self.x * rhs,
	    y: self.y * rhs,
	}
    }
}

////////// divide point with scalar ////////////////////////////////////////////
impl<T: Div<Output = T> + Copy> Div<T> for Point2D<T> {
    type Output = Self;

    fn div(self, rhs: T) -> Self {
	Self {
	    x: self.x / rhs,
	    y: self.y / rhs,
	}
    }
}

impl<T: Div<Output = T> + Copy> DivAssign<T> for Point2D<T> {
    fn div_assign(&mut self, rhs: T) {
	*self = Self {
	    x: self.x / rhs,
	    y: self.y / rhs,
	}
    }
}

impl<T: Neg<Output = T>> Neg for Point2D<T> {
    type Output = Self;

    fn neg(self) -> Self {
	Self {
	    x: -self.x,
	    y: -self.y,
	}
    }
}

impl<T> From<(T, T)> for Point2D<T> {
    fn from(item: (T, T)) -> Self {
        Point2D {
            x: item.0,
            y: item.1,
        }
    }
}

impl<T> From<Point2D<T>> for (T, T) {
    fn from(item: Point2D<T>) -> Self {
        (item.x, item.y)
    }
}

impl From<Degrees> for Point2D<f64> {
    fn from(item: Degrees) -> Self {
	let r = item.0.to_radians();
        Point2D {
            x: r.cos(),
            y: r.sin(),
        }
    }
}

impl From<Radians> for Point2D<f64> {
    fn from(item: Radians) -> Self {
        Point2D {
            x: item.0.cos(),
            y: item.0.sin(),
        }
    }
}

#[derive(Debug, Default, PartialEq, Clone, Copy)]
pub struct Degrees(pub f64);
#[derive(Debug, Default, PartialEq, Clone, Copy)]
pub struct Radians(pub f64);

impl Degrees {
    #[allow(dead_code)]
    fn to_radians(&self) -> Radians {
	Radians(self.0.to_radians())
    }
}

impl Radians {
    #[allow(dead_code)]
    fn to_degrees(&self) -> Degrees {
	Degrees(self.0.to_degrees())
    }
}

#[macro_export]
macro_rules! rect {
    ( $x:expr, $y:expr ) => {
        Rect { x: $x, y: $y }
    };
}

#[derive(Default)]
pub struct Rect<T> {
    pub width: T,
    pub height: T,
}

impl<T: Mul<Output = T> + Copy> Rect<T> {
    #[allow(dead_code)]
    pub fn area(&self) -> T {
        self.width * self.height
    }
}

impl<T> From<(T, T)> for Rect<T> {
    fn from(item: (T, T)) -> Self {
        Rect {
            width: item.0,
            height: item.1,
        }
    }
}

#[macro_export]
macro_rules! hashmap {
    ($($k:expr => $v:expr),*) => {
	{
	    let mut map = std::collections::HashMap::new();
	    $(map.insert($k, $v);)*
	    map
	}
    }
}

#[cfg(test)]
mod tests {
    use super::*;

    #[test]
    fn immutable_copy_of_point() {
        let a = point!(0, 0);
        let mut b = a; // Copy
        assert_eq!(a, b); // PartialEq
        b.x = 1;
        assert_ne!(a, b); // PartialEq
    }

    #[test]
    fn add_points() {
        let mut a = point!(1, 0);
        assert_eq!(a + point!(2, 2), point!(3, 2)); // Add
        a += point!(2, 2); // AddAssign
        assert_eq!(a, point!(3, 2));
        assert_eq!(point!(1, 0) + (2, 3), point!(3, 3));
    }

    #[test]
    fn sub_points() {
        let mut a = point!(1, 0);
        assert_eq!(a - point!(2, 2), point!(-1, -2));
        a -= point!(2, 2);
        assert_eq!(a, point!(-1, -2));
        assert_eq!(point!(1, 0) - (2, 3), point!(-1, -3));
    }

    #[test]
    fn mul_points() {
        let mut a = point!(1, 2);
        assert_eq!(a * 2, point!(2, 4));
        assert_eq!(a * point!(2, 3), point!(2, 6));
        a *= 2;
        assert_eq!(a, point!(2, 4));
        a *= point!(3, 1);
        assert_eq!(a, point!(6, 4));
        assert_eq!(point!(1, 0) * (2, 3), point!(2, 0));
    }

    #[test]
    fn div_points() {
        let mut a = point!(4, 8);
        assert_eq!(a / 2, point!(2, 4));
        assert_eq!(a / point!(2, 4), point!(2, 2));
        a /= 2;
        assert_eq!(a, point!(2, 4));
        a /= point!(2, 4);
        assert_eq!(a, point!(1, 1));
        assert_eq!(point!(6, 3) / (2, 3), point!(3, 1));
    }

    #[test]
    fn neg_point() {
        assert_eq!(point!(1, 1), -point!(-1, -1));
    }

    #[test]
    fn angles() {
	assert_eq!(Radians(0.0).to_degrees(), Degrees(0.0));
	assert_eq!(Radians(std::f64::consts::PI).to_degrees(), Degrees(180.0));
	assert_eq!(Degrees(180.0).to_radians(), Radians(std::f64::consts::PI));
	assert!((Point2D::from(Degrees(90.0)) - point!(0.0, 1.0)).length() < 0.001);
	assert!((Point2D::from(Radians(std::f64::consts::FRAC_PI_2)) - point!(0.0, 1.0)).length() < 0.001);
    }

    #[test]
    fn area_for_rect_of_multipliable_type() {
        let r: Rect<_> = (30, 20).into(); // the Into trait uses the From trait
        assert_eq!(r.area(), 30 * 20);
        // let a = Rect::from(("a".to_string(), "b".to_string())).area(); // this doesn't work, because area() is not implemented for String
    }
}
Commit	Line	Data
	1	use std::ops::{Add, AddAssign, Sub, SubAssign, Mul, MulAssign, Div, DivAssign, Neg};
	2
	3	#[macro_export]
	4	macro_rules! point {
	5	( $x:expr, $y:expr ) => {
	6	Point2D { x: $x, y: $y }
	7	};
	8	}
	9
	10	#[derive(Debug, Default, Copy, Clone, PartialEq)]
	11	pub struct Point2D<T> {
	12	pub x: T,
	13	pub y: T,
	14	}
	15
	16	impl Point2D<f64> {
	17	pub fn length(&self) -> f64 {
	18	((self.x * self.x) + (self.y * self.y)).sqrt()
	19	}
	20
	21	pub fn normalized(&self) -> Self {
	22	let l = self.length();
	23	Self {
	24	x: self.x / l,
	25	y: self.y / l,
	26	}
	27	}
	28
	29	pub fn to_radians(&self) -> Radians {
	30	Radians(self.y.atan2(self.x))
	31	}
	32
	33	pub fn to_degrees(&self) -> Degrees {
	34	self.to_radians().to_degrees()
	35	}
	36
	37	pub fn to_i32(self) -> Point2D<i32> {
	38	Point2D {
	39	x: self.x as i32,
	40	y: self.y as i32,
	41	}
	42	}
	43	}
	44
	45	macro_rules! point_op {
	46	($op:tt, $trait:ident($fn:ident), $trait_assign:ident($fn_assign:ident), $rhs:ident = $Rhs:ty => $x:expr, $y:expr) => {
	47	impl<T: $trait<Output = T>> $trait<$Rhs> for Point2D<T> {
	48	type Output = Self;
	49
	50	fn $fn(self, $rhs: $Rhs) -> Self {
	51	Self {
	52	x: self.x $op $x,
	53	y: self.y $op $y,
	54	}
	55	}
	56	}
	57
	58	impl<T: $trait<Output = T> + Copy> $trait_assign<$Rhs> for Point2D<T> {
	59	fn $fn_assign(&mut self, $rhs: $Rhs) {
	60	*self = Self {
	61	x: self.x $op $x,
	62	y: self.y $op $y,
	63	}
	64	}
	65	}
	66	}
	67	}
	68
	69	point_op!(+, Add(add), AddAssign(add_assign), rhs = Point2D<T> => rhs.x, rhs.y);
	70	point_op!(-, Sub(sub), SubAssign(sub_assign), rhs = Point2D<T> => rhs.x, rhs.y);
	71	point_op!(*, Mul(mul), MulAssign(mul_assign), rhs = Point2D<T> => rhs.x, rhs.y);
	72	point_op!(/, Div(div), DivAssign(div_assign), rhs = Point2D<T> => rhs.x, rhs.y);
	73	point_op!(+, Add(add), AddAssign(add_assign), rhs = (T, T) => rhs.0, rhs.1);
	74	point_op!(-, Sub(sub), SubAssign(sub_assign), rhs = (T, T) => rhs.0, rhs.1);
	75	point_op!(*, Mul(mul), MulAssign(mul_assign), rhs = (T, T) => rhs.0, rhs.1);
	76	point_op!(/, Div(div), DivAssign(div_assign), rhs = (T, T) => rhs.0, rhs.1);
	77
	78	////////// multiply point with scalar //////////////////////////////////////////
	79	impl<T: Mul<Output = T> + Copy> Mul<T> for Point2D<T> {
	80	type Output = Self;
	81
	82	fn mul(self, rhs: T) -> Self {
	83	Self {
	84	x: self.x * rhs,
	85	y: self.y * rhs,
	86	}
	87	}
	88	}
	89
	90	impl<T: Mul<Output = T> + Copy> MulAssign<T> for Point2D<T> {
	91	fn mul_assign(&mut self, rhs: T) {
	92	*self = Self {
	93	x: self.x * rhs,
	94	y: self.y * rhs,
	95	}
	96	}
	97	}
	98
	99	////////// divide point with scalar ////////////////////////////////////////////
	100	impl<T: Div<Output = T> + Copy> Div<T> for Point2D<T> {
	101	type Output = Self;
	102
	103	fn div(self, rhs: T) -> Self {
	104	Self {
	105	x: self.x / rhs,
	106	y: self.y / rhs,
	107	}
	108	}
	109	}
	110
	111	impl<T: Div<Output = T> + Copy> DivAssign<T> for Point2D<T> {
	112	fn div_assign(&mut self, rhs: T) {
	113	*self = Self {
	114	x: self.x / rhs,
	115	y: self.y / rhs,
	116	}
	117	}
	118	}
	119
	120	impl<T: Neg<Output = T>> Neg for Point2D<T> {
	121	type Output = Self;
	122
	123	fn neg(self) -> Self {
	124	Self {
	125	x: -self.x,
	126	y: -self.y,
	127	}
	128	}
	129	}
	130
	131	impl<T> From<(T, T)> for Point2D<T> {
	132	fn from(item: (T, T)) -> Self {
	133	Point2D {
	134	x: item.0,
	135	y: item.1,
	136	}
	137	}
	138	}
	139
	140	impl<T> From<Point2D<T>> for (T, T) {
	141	fn from(item: Point2D<T>) -> Self {
	142	(item.x, item.y)
	143	}
	144	}
	145
	146	impl From<Degrees> for Point2D<f64> {
	147	fn from(item: Degrees) -> Self {
	148	let r = item.0.to_radians();
	149	Point2D {
	150	x: r.cos(),
	151	y: r.sin(),
	152	}
	153	}
	154	}
	155
	156	impl From<Radians> for Point2D<f64> {
	157	fn from(item: Radians) -> Self {
	158	Point2D {
	159	x: item.0.cos(),
	160	y: item.0.sin(),
	161	}
	162	}
	163	}
	164
	165	#[derive(Debug, Default, PartialEq, Clone, Copy)]
	166	pub struct Degrees(pub f64);
	167	#[derive(Debug, Default, PartialEq, Clone, Copy)]
	168	pub struct Radians(pub f64);
	169
	170	impl Degrees {
	171	#[allow(dead_code)]
	172	fn to_radians(&self) -> Radians {
	173	Radians(self.0.to_radians())
	174	}
	175	}
	176
	177	impl Radians {
	178	#[allow(dead_code)]
	179	fn to_degrees(&self) -> Degrees {
	180	Degrees(self.0.to_degrees())
	181	}
	182	}
	183
	184	#[macro_export]
	185	macro_rules! rect {
	186	( $x:expr, $y:expr ) => {
	187	Rect { x: $x, y: $y }
	188	};
	189	}
	190
	191	#[derive(Default)]
	192	pub struct Rect<T> {
	193	pub width: T,
	194	pub height: T,
	195	}
	196
	197	impl<T: Mul<Output = T> + Copy> Rect<T> {
	198	#[allow(dead_code)]
	199	pub fn area(&self) -> T {
	200	self.width * self.height
	201	}
	202	}
	203
	204	impl<T> From<(T, T)> for Rect<T> {
	205	fn from(item: (T, T)) -> Self {
	206	Rect {
	207	width: item.0,
	208	height: item.1,
	209	}
	210	}
	211	}
	212
	213	#[macro_export]
	214	macro_rules! hashmap {
	215	($($k:expr => $v:expr),*) => {
	216	{
	217	let mut map = std::collections::HashMap::new();
	218	$(map.insert($k, $v);)*
	219	map
	220	}
	221	}
	222	}
	223
	224	#[cfg(test)]
	225	mod tests {
	226	use super::*;
	227
	228	#[test]
	229	fn immutable_copy_of_point() {
	230	let a = point!(0, 0);
	231	let mut b = a; // Copy
	232	assert_eq!(a, b); // PartialEq
	233	b.x = 1;
	234	assert_ne!(a, b); // PartialEq
	235	}
	236
	237	#[test]
	238	fn add_points() {
	239	let mut a = point!(1, 0);
	240	assert_eq!(a + point!(2, 2), point!(3, 2)); // Add
	241	a += point!(2, 2); // AddAssign
	242	assert_eq!(a, point!(3, 2));
	243	assert_eq!(point!(1, 0) + (2, 3), point!(3, 3));
	244	}
	245
	246	#[test]
	247	fn sub_points() {
	248	let mut a = point!(1, 0);
	249	assert_eq!(a - point!(2, 2), point!(-1, -2));
	250	a -= point!(2, 2);
	251	assert_eq!(a, point!(-1, -2));
	252	assert_eq!(point!(1, 0) - (2, 3), point!(-1, -3));
	253	}
	254
	255	#[test]
	256	fn mul_points() {
	257	let mut a = point!(1, 2);
	258	assert_eq!(a * 2, point!(2, 4));
	259	assert_eq!(a * point!(2, 3), point!(2, 6));
	260	a *= 2;
	261	assert_eq!(a, point!(2, 4));
	262	a *= point!(3, 1);
	263	assert_eq!(a, point!(6, 4));
	264	assert_eq!(point!(1, 0) * (2, 3), point!(2, 0));
	265	}
	266
	267	#[test]
	268	fn div_points() {
	269	let mut a = point!(4, 8);
	270	assert_eq!(a / 2, point!(2, 4));
	271	assert_eq!(a / point!(2, 4), point!(2, 2));
	272	a /= 2;
	273	assert_eq!(a, point!(2, 4));
	274	a /= point!(2, 4);
	275	assert_eq!(a, point!(1, 1));
	276	assert_eq!(point!(6, 3) / (2, 3), point!(3, 1));
	277	}
	278
	279	#[test]
	280	fn neg_point() {
	281	assert_eq!(point!(1, 1), -point!(-1, -1));
	282	}
	283
	284	#[test]
	285	fn angles() {
	286	assert_eq!(Radians(0.0).to_degrees(), Degrees(0.0));
	287	assert_eq!(Radians(std::f64::consts::PI).to_degrees(), Degrees(180.0));
	288	assert_eq!(Degrees(180.0).to_radians(), Radians(std::f64::consts::PI));
	289	assert!((Point2D::from(Degrees(90.0)) - point!(0.0, 1.0)).length() < 0.001);
	290	assert!((Point2D::from(Radians(std::f64::consts::FRAC_PI_2)) - point!(0.0, 1.0)).length() < 0.001);
	291	}
	292
	293	#[test]
	294	fn area_for_rect_of_multipliable_type() {
	295	let r: Rect<_> = (30, 20).into(); // the Into trait uses the From trait
	296	assert_eq!(r.area(), 30 * 20);
	297	// let a = Rect::from(("a".to_string(), "b".to_string())).area(); // this doesn't work, because area() is not implemented for String
	298	}
	299	}