| // Copyright 2018 The Servo Project Developers. See the COPYRIGHT |
| // file at the top-level directory of this distribution. |
| // |
| // Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or |
| // http://www.apache.org/licenses/LICENSE-2.0> or the MIT license |
| // <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your |
| // option. This file may not be copied, modified, or distributed |
| // except according to those terms. |
| |
| use sys; |
| |
| /// Direction of text flow during layout. |
| /// |
| /// This maps to the [`hb_direction_t`] from |
| /// [`harfbuzz-sys`]. It can be converted to |
| /// or from `hb_direction_t` using the [`From`] |
| /// and [`Into`] traits: |
| /// |
| /// ``` |
| /// # use harfbuzz::{Direction, sys}; |
| /// assert_eq!(Direction::from(sys::HB_DIRECTION_LTR), Direction::LTR); |
| /// assert_eq!(sys::hb_direction_t::from(Direction::BTT), sys::HB_DIRECTION_BTT); |
| /// |
| /// let hb_dir: sys::hb_direction_t = Direction::LTR.into(); |
| /// assert_eq!(hb_dir, sys::HB_DIRECTION_LTR); |
| /// |
| /// let dir: Direction = sys::HB_DIRECTION_TTB.into(); |
| /// assert_eq!(dir, Direction::TTB); |
| /// ``` |
| /// |
| /// [`hb_direction_t`]: ../harfbuzz_sys/type.hb_direction_t.html |
| /// [`harfbuzz-sys`]: ../harfbuzz_sys/index.html |
| /// [`From`]: https://doc.rust-lang.org/std/convert/trait.From.html |
| /// [`Into`]: https://doc.rust-lang.org/std/convert/trait.Into.html |
| #[derive(Copy, Clone, Debug, PartialEq, PartialOrd)] |
| pub enum Direction { |
| /// Initial, unset direction. |
| /// |
| /// This corresponds to [`HB_DIRECTION_INVALID`]. |
| /// |
| /// [`HB_DIRECTION_INVALID`]: ../harfbuzz_sys/constant.HB_DIRECTION_INVALID.html |
| Invalid, |
| /// Text is set horizontally from left to right. |
| /// |
| /// This corresponds to [`HB_DIRECTION_LTR`]. |
| /// |
| /// [`HB_DIRECTION_LTR`]: ../harfbuzz_sys/constant.HB_DIRECTION_LTR.html |
| LTR, |
| /// Text is set horizontally from right to left. |
| /// |
| /// This corresponds to [`HB_DIRECTION_RTL`]. |
| /// |
| /// [`HB_DIRECTION_RTL`]: ../harfbuzz_sys/constant.HB_DIRECTION_RTL.html |
| RTL, |
| /// Text is set vertically from top to bottom. |
| /// |
| /// This corresponds to [`HB_DIRECTION_TTB`]. |
| /// |
| /// [`HB_DIRECTION_TTB`]: ../harfbuzz_sys/constant.HB_DIRECTION_TTB.html |
| TTB, |
| /// Text is set vertically from bottom to top. |
| /// |
| /// This corresponds to [`HB_DIRECTION_BTT`]. |
| /// |
| /// [`HB_DIRECTION_BTT`]: ../harfbuzz_sys/constant.HB_DIRECTION_BTT.html |
| BTT, |
| } |
| |
| impl From<sys::hb_direction_t> for Direction { |
| fn from(s: sys::hb_direction_t) -> Self { |
| match s { |
| sys::HB_DIRECTION_INVALID => Direction::Invalid, |
| sys::HB_DIRECTION_LTR => Direction::LTR, |
| sys::HB_DIRECTION_RTL => Direction::RTL, |
| sys::HB_DIRECTION_TTB => Direction::TTB, |
| sys::HB_DIRECTION_BTT => Direction::BTT, |
| _ => Direction::Invalid, |
| } |
| } |
| } |
| |
| impl From<Direction> for sys::hb_direction_t { |
| fn from(s: Direction) -> Self { |
| match s { |
| Direction::Invalid => sys::HB_DIRECTION_INVALID, |
| Direction::LTR => sys::HB_DIRECTION_LTR, |
| Direction::RTL => sys::HB_DIRECTION_RTL, |
| Direction::TTB => sys::HB_DIRECTION_TTB, |
| Direction::BTT => sys::HB_DIRECTION_BTT, |
| } |
| } |
| } |