circles/
circles.rs

1//! Example program drawing circles on a page.
2extern crate pdf_canvas;
3
4use pdf_canvas::graphicsstate::Color;
5use pdf_canvas::Pdf;
6use std::f32::consts::PI;
7
8/// Create a `circles.pdf` file, with a single page containg a circle
9/// stroked in black, overwritten with a circle in a finer yellow
10/// stroke.
11/// The black circle is drawn using the `Canvas.circle` method,
12/// which approximates a circle with four bezier curves.
13/// The yellow circle is drawn as a 200-sided polygon.
14fn main() {
15    // Open our pdf document.
16    let mut document = Pdf::create("circles.pdf").unwrap();
17
18    // Add a 400x400 pt page.
19
20    // Render-page writes the pdf file structure for a page and
21    // creates a Canvas which is sent to the function that is the last
22    // argument of the render_page method.
23    // That function then puts content on the page by calling methods
24    // on the canvas.
25    document
26        .render_page(400.0, 400.0, |c| {
27            let (x, y) = (200.0, 200.0);
28            let r = 190.0;
29
30            // Set a wide black pen and stroke a circle
31            c.set_stroke_color(Color::rgb(0, 0, 0))?;
32            c.set_line_width(2.0)?;
33            c.circle(x, y, r)?;
34            c.stroke()?;
35
36            // Set a finer yellow pen and stroke a 200-sided polygon
37            c.set_stroke_color(Color::rgb(255, 230, 150))?;
38            c.set_line_width(1.0)?;
39            c.move_to(x + r, y)?;
40            let sides: u8 = 200;
41            for n in 1..sides {
42                let phi = f32::from(n) * 2.0 * PI / f32::from(sides);
43                c.line_to(x + r * phi.cos(), y + r * phi.sin())?;
44            }
45            c.close_and_stroke()
46        })
47        .unwrap();
48    document.finish().unwrap();
49}
circles/circles.rs

circles/
circles.rs
