blob: 56b41da26965f86e56bc609f4ca127f457429393 [file] [log] [blame]
extern crate rusttype;
use rusttype::{point, FontCollection, PositionedGlyph, Scale};
use std::io::Write;
fn main() {
let font_data = include_bytes!("../fonts/wqy-microhei/WenQuanYiMicroHei.ttf");
let collection = FontCollection::from_bytes(font_data as &[u8]).unwrap_or_else(|e| {
panic!("error constructing a FontCollection from bytes: {}", e);
});
let font = collection.into_font() // only succeeds if collection consists of one font
.unwrap_or_else(|e| {
panic!("error turning FontCollection into a Font: {}", e);
});
// Desired font pixel height
let height: f32 = 12.4; // to get 80 chars across (fits most terminals); adjust as desired
let pixel_height = height.ceil() as usize;
// 2x scale in x direction to counter the aspect ratio of monospace characters.
let scale = Scale {
x: height * 2.0,
y: height,
};
// The origin of a line of text is at the baseline (roughly where
// non-descending letters sit). We don't want to clip the text, so we shift
// it down with an offset when laying it out. v_metrics.ascent is the
// distance between the baseline and the highest edge of any glyph in
// the font. That's enough to guarantee that there's no clipping.
let v_metrics = font.v_metrics(scale);
let offset = point(0.0, v_metrics.ascent);
// Glyphs to draw for "RustType". Feel free to try other strings.
let glyphs: Vec<PositionedGlyph> = font.layout("RustType", scale, offset).collect();
// Find the most visually pleasing width to display
let width = glyphs
.iter()
.rev()
.map(|g| g.position().x as f32 + g.unpositioned().h_metrics().advance_width)
.next()
.unwrap_or(0.0)
.ceil() as usize;
println!("width: {}, height: {}", width, pixel_height);
// Rasterise directly into ASCII art.
let mut pixel_data = vec![b'@'; width * pixel_height];
let mapping = b"@%#x+=:-. "; // The approximation of greyscale
let mapping_scale = (mapping.len() - 1) as f32;
for g in glyphs {
if let Some(bb) = g.pixel_bounding_box() {
g.draw(|x, y, v| {
// v should be in the range 0.0 to 1.0
let i = (v * mapping_scale + 0.5) as usize;
// so something's wrong if you get $ in the output.
let c = mapping.get(i).cloned().unwrap_or(b'$');
let x = x as i32 + bb.min.x;
let y = y as i32 + bb.min.y;
// There's still a possibility that the glyph clips the boundaries of the bitmap
if x >= 0 && x < width as i32 && y >= 0 && y < pixel_height as i32 {
let x = x as usize;
let y = y as usize;
pixel_data[(x + y * width)] = c;
}
})
}
}
// Print it out
let stdout = ::std::io::stdout();
let mut handle = stdout.lock();
for j in 0..pixel_height {
handle
.write_all(&pixel_data[j * width..(j + 1) * width])
.unwrap();
handle.write_all(b"\n").unwrap();
}
}