| // Copyright 2016 Joe Wilm, The Alacritty Project Contributors |
| // |
| // Licensed under the Apache License, Version 2.0 (the "License"); |
| // you may not use this file except in compliance with the License. |
| // You may obtain a copy of the License at |
| // |
| // http://www.apache.org/licenses/LICENSE-2.0 |
| // |
| // Unless required by applicable law or agreed to in writing, software |
| // distributed under the License is distributed on an "AS IS" BASIS, |
| // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| // See the License for the specific language governing permissions and |
| // limitations under the License. |
| |
| //! Helpers for creating different cursor glyphs from font metrics |
| |
| use std::cmp; |
| |
| use serde::Deserialize; |
| |
| use font::{Metrics, RasterizedGlyph}; |
| |
| use crate::ansi::CursorStyle; |
| |
| /// Width/Height of the cursor relative to the font width |
| pub const CURSOR_WIDTH_PERCENTAGE: i32 = 15; |
| |
| /// A key for caching cursor glyphs |
| #[derive(Debug, Eq, PartialEq, Copy, Clone, Hash, Deserialize)] |
| pub struct CursorKey { |
| pub style: CursorStyle, |
| pub is_wide: bool, |
| } |
| |
| pub fn get_cursor_glyph( |
| cursor: CursorStyle, |
| metrics: Metrics, |
| offset_x: i8, |
| offset_y: i8, |
| is_wide: bool, |
| ) -> RasterizedGlyph { |
| // Calculate the cell metrics |
| let height = metrics.line_height as i32 + i32::from(offset_y); |
| let mut width = metrics.average_advance as i32 + i32::from(offset_x); |
| let line_width = cmp::max(width * CURSOR_WIDTH_PERCENTAGE / 100, 1); |
| |
| // Double the cursor width if it's above a double-width glyph |
| if is_wide { |
| width *= 2; |
| } |
| |
| match cursor { |
| CursorStyle::HollowBlock => get_box_cursor_glyph(height, width, line_width), |
| CursorStyle::Underline => get_underline_cursor_glyph(width, line_width), |
| CursorStyle::Beam => get_beam_cursor_glyph(height, line_width), |
| CursorStyle::Block => get_block_cursor_glyph(height, width), |
| CursorStyle::Hidden => RasterizedGlyph::default(), |
| } |
| } |
| |
| // Returns a custom underline cursor character |
| pub fn get_underline_cursor_glyph(width: i32, line_width: i32) -> RasterizedGlyph { |
| // Create a new rectangle, the height is relative to the font width |
| let buf = vec![255u8; (width * line_width * 3) as usize]; |
| |
| // Create a custom glyph with the rectangle data attached to it |
| RasterizedGlyph { c: ' ', top: line_width, left: 0, height: line_width, width, buf } |
| } |
| |
| // Returns a custom beam cursor character |
| pub fn get_beam_cursor_glyph(height: i32, line_width: i32) -> RasterizedGlyph { |
| // Create a new rectangle that is at least one pixel wide |
| let buf = vec![255u8; (line_width * height * 3) as usize]; |
| |
| // Create a custom glyph with the rectangle data attached to it |
| RasterizedGlyph { c: ' ', top: height, left: 0, height, width: line_width, buf } |
| } |
| |
| // Returns a custom box cursor character |
| pub fn get_box_cursor_glyph(height: i32, width: i32, line_width: i32) -> RasterizedGlyph { |
| // Create a new box outline rectangle |
| let mut buf = Vec::with_capacity((width * height * 3) as usize); |
| for y in 0..height { |
| for x in 0..width { |
| if y < line_width |
| || y >= height - line_width |
| || x < line_width |
| || x >= width - line_width |
| { |
| buf.append(&mut vec![255u8; 3]); |
| } else { |
| buf.append(&mut vec![0u8; 3]); |
| } |
| } |
| } |
| |
| // Create a custom glyph with the rectangle data attached to it |
| RasterizedGlyph { c: ' ', top: height, left: 0, height, width, buf } |
| } |
| |
| // Returns a custom block cursor character |
| pub fn get_block_cursor_glyph(height: i32, width: i32) -> RasterizedGlyph { |
| // Create a completely filled glyph |
| let buf = vec![255u8; (width * height * 3) as usize]; |
| |
| // Create a custom glyph with the rectangle data attached to it |
| RasterizedGlyph { c: ' ', top: height, left: 0, height, width, buf } |
| } |