/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
* file, You can obtain one at https://mozilla.org/MPL/2.0/. */
use std::f32;
use app_units::{Au, MAX_AU, MIN_AU};
use euclid::default::{Point2D as UntypedPoint2D, Rect as UntypedRect, Size2D as UntypedSize2D};
use euclid::{Box2D, Length, Point2D, SideOffsets2D, Size2D, Vector2D};
use malloc_size_of_derive::MallocSizeOf;
use webrender_api::units::{FramebufferPixel, LayoutPoint, LayoutRect, LayoutSize};
// Units for use with euclid::length and euclid::scale_factor.
pub type FramebufferUintLength = Length<u32, FramebufferPixel>;
/// A normalized "pixel" at the default resolution for the display.
///
/// Like the CSS "px" unit, the exact physical size of this unit may vary between devices, but it
/// should approximate a device-independent reference length. This unit corresponds to Android's
/// "density-independent pixel" (dip), Mac OS X's "point", and Windows "device-independent pixel."
///
/// The relationship between DevicePixel and DeviceIndependentPixel is defined by the OS. On most low-dpi
/// screens, one DeviceIndependentPixel is equal to one DevicePixel. But on high-density screens it can be
/// some larger number. For example, by default on Apple "retina" displays, one DeviceIndependentPixel equals
/// two DevicePixels. On Android "MDPI" displays, one DeviceIndependentPixel equals 1.5 device pixels.
///
/// The ratio between DeviceIndependentPixel and DevicePixel for a given display be found by calling
/// `servo::windowing::WindowMethods::hidpi_factor`.
#[derive(Clone, Copy, Debug, MallocSizeOf)]
pub enum DeviceIndependentPixel {}
pub type DeviceIndependentIntRect = Box2D<i32, DeviceIndependentPixel>;
pub type DeviceIndependentIntPoint = Point2D<i32, DeviceIndependentPixel>;
pub type DeviceIndependentIntSize = Size2D<i32, DeviceIndependentPixel>;
pub type DeviceIndependentIntLength = Length<i32, DeviceIndependentPixel>;
pub type DeviceIndependentIntSideOffsets = SideOffsets2D<i32, DeviceIndependentPixel>;
pub type DeviceIndependentIntVector2D = Vector2D<i32, DeviceIndependentPixel>;
pub type DeviceIndependentRect = Box2D<f32, DeviceIndependentPixel>;
pub type DeviceIndependentBox2D = Box2D<f32, DeviceIndependentPixel>;
pub type DeviceIndependentPoint = Point2D<f32, DeviceIndependentPixel>;
pub type DeviceIndependentVector2D = Vector2D<f32, DeviceIndependentPixel>;
pub type DeviceIndependentSize = Size2D<f32, DeviceIndependentPixel>;
// An Au is an "App Unit" and represents 1/60th of a CSS pixel. It was
// originally proposed in 2002 as a standard unit of measure in Gecko.
// See https://bugzilla.mozilla.org/show_bug.cgi?id=177805 for more info.
pub trait MaxRect {
fn max_rect() -> Self;
}
impl MaxRect for UntypedRect<Au> {
#[inline]
fn max_rect() -> Self {
Self::new(
UntypedPoint2D::new(MIN_AU / 2, MIN_AU / 2),
UntypedSize2D::new(MAX_AU, MAX_AU),
)
}
}
impl MaxRect for LayoutRect {
#[inline]
fn max_rect() -> Self {
Self::from_origin_and_size(
LayoutPoint::new(f32::MIN / 2.0, f32::MIN / 2.0),
LayoutSize::new(f32::MAX, f32::MAX),
)
}
}
/// A helper function to convert a rect of `f32` pixels to a rect of app units.
pub fn f32_rect_to_au_rect(rect: UntypedRect<f32>) -> UntypedRect<Au> {
UntypedRect::new(
Point2D::new(
Au::from_f32_px(rect.origin.x),
Au::from_f32_px(rect.origin.y),
),
Size2D::new(
Au::from_f32_px(rect.size.width),
Au::from_f32_px(rect.size.height),
),
)
}
/// A helper function to convert a rect of `Au` pixels to a rect of f32 units.
pub fn au_rect_to_f32_rect(rect: UntypedRect<Au>) -> UntypedRect<f32> {
UntypedRect::new(
Point2D::new(rect.origin.x.to_f32_px(), rect.origin.y.to_f32_px()),
Size2D::new(rect.size.width.to_f32_px(), rect.size.height.to_f32_px()),
)
}