use std::cmp::min;
use vec::{ToVec2, Vec2};
#[derive(PartialEq,Debug,Clone)]
pub struct Position {
pub x: Offset,
pub y: Offset,
}
impl Position {
pub fn new(x: Offset, y: Offset) -> Self {
Position { x: x, y: y }
}
pub fn center() -> Self {
Position::new(Offset::Center, Offset::Center)
}
pub fn absolute<T: ToVec2>(offset: T) -> Self {
let offset = offset.to_vec2();
Position::new(Offset::Absolute(offset.x), Offset::Absolute(offset.y))
}
pub fn parent<T: ToVec2>(offset: T) -> Self {
let offset = offset.to_vec2();
Position::new(Offset::Parent(offset.x), Offset::Parent(offset.y))
}
pub fn compute_offset(&self, size: Vec2, available: Vec2, parent: Vec2)
-> Vec2 {
Vec2::new(self.x.compute_offset(size.x, available.x, parent.x),
self.y.compute_offset(size.y, available.y, parent.y))
}
}
#[derive(PartialEq,Debug,Clone)]
pub enum Offset {
Center,
Absolute(usize),
Parent(usize), }
impl Offset {
pub fn compute_offset(&self, size: usize, available: usize, parent: usize)
-> usize {
match *self {
Offset::Center => (available - size) / 2,
Offset::Absolute(offset) => min(offset, available - size),
Offset::Parent(offset) => min(parent + offset, available - size),
}
}
}