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@tetsu-koba tetsu-koba/00_rust_cairo

Last active Sep 29, 2018
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2D graphics animation tool using cairo rust binding and ffmpeg
2D graphics animation tool using cairo rust binding and ffmpeg
extern crate cairo;
use std::io::Write;
use std::process::{Command, Stdio};
use std::f64::consts::PI;
use cairo::{ImageSurface, Format, Context};
fn draw(surface: &ImageSurface, f: i32) {
let cr = Context::new(surface);
let width = surface.get_width() as f64;
let height = surface.get_height() as f64;
let dx = f as f64 * 1.0;
cr.set_source_rgb(1.0, 1.0, 1.0);
cr.paint();
let cx = width / 2.0;
let cy = height / 2.0;
let r = cy;
let cstart = -0.5 * PI;
let cend = cstart + 2.0 * PI * ((f + 1) as f64) / 300.0;
cr.move_to(cx, cy);
cr.line_to(cx, 0.0);
cr.arc(cx, cy, r, cstart, cend);
cr.line_to(cx, cy);
cr.set_source_rgba(0.0, 0.5, 0.0, 0.2);
cr.fill();
cr.select_font_face(
"sans-serif",
cairo::FontSlant::Normal,
cairo::FontWeight::Normal,
);
cr.set_font_size(70.0);
cr.move_to(600.0 - dx, 100.0);
cr.set_source_rgb(0.0, 0.0, 1.0);
cr.show_text("Hello, world! 1234567890");
cr.fill();
}
fn make_cmdline(width: i32, height: i32, framerate: i32) -> String {
format!(
"ffmpeg -f rawvideo -pix_fmt bgra -s {width}x{height} -i - -pix_fmt yuv420p -r {framerate} -y out.mp4",
width = width,
height = height,
framerate = framerate
)
}
fn make_movie(width: i32, height: i32, framerate: i32, frames: i32) {
let mut surface =
ImageSurface::create(Format::ARgb32, width, height).expect("Couldn't create surface");
let mut child = Command::new("/bin/sh")
.args(&["-c", &make_cmdline(width, height, framerate)])
.stdin(Stdio::piped())
.spawn()
.expect("failed to execute child");
{
// limited borrow of stdin
let child_stdin = child.stdin.as_mut().expect("failed to get stdin");
(0..frames).for_each(|f| {
draw(&surface, f);
let d = surface.get_data().expect("Failed to get_data");
child_stdin.write_all(&d).expect("Failed to write to file");
});
}
child.wait().expect("child process wasn't running");
}
fn main() {
make_movie(1280, 720, 30, 300);
}
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