use svgdom::{
Align,
AspectRatio,
Transform,
};
use geom::*;
pub fn view_box_to_transform(
view_box: Rect,
aspect: AspectRatio,
img_size: Size,
) -> Transform {
let vr = view_box;
let sx = img_size.width / vr.width;
let sy = img_size.height / vr.height;
let (sx, sy) = if aspect.align == Align::None {
(sx, sy)
} else {
let s = if aspect.slice {
if sx < sy { sy } else { sx }
} else {
if sx > sy { sy } else { sx }
};
(s, s)
};
let x = -vr.x * sx;
let y = -vr.y * sy;
let w = img_size.width - vr.width * sx;
let h = img_size.height - vr.height * sy;
let pos = aligned_pos(aspect.align, x, y, w, h);
Transform::new(sx, 0.0, 0.0, sy, pos.x, pos.y)
}
pub fn aligned_pos(align: Align, x: f64, y: f64, w: f64, h: f64) -> Point {
match align {
Align::None => Point::new(x, y ),
Align::XMinYMin => Point::new(x, y ),
Align::XMidYMin => Point::new(x + w / 2.0, y ),
Align::XMaxYMin => Point::new(x + w, y ),
Align::XMinYMid => Point::new(x, y + h / 2.0),
Align::XMidYMid => Point::new(x + w / 2.0, y + h / 2.0),
Align::XMaxYMid => Point::new(x + w, y + h / 2.0),
Align::XMinYMax => Point::new(x, y + h ),
Align::XMidYMax => Point::new(x + w / 2.0, y + h ),
Align::XMaxYMax => Point::new(x + w, y + h ),
}
}