nannou_svg_draw_example.rs

use nannou::prelude::*;

fn main() {
    nannou::app(model).run();
}

struct Model {
    svg_render_frame: u64,
}

fn model(app: &App) -> Model {
    app.new_window()
        .mouse_pressed(mouse_pressed)
        .view(view)
        .build()
        .unwrap();

    Model {
        svg_render_frame: 0,
    }
}

fn mouse_pressed(app: &App, model: &mut Model, button: MouseButton) {
    if let MouseButton::Left = button {
        model.svg_render_frame = app.elapsed_frames() + 1;
    }
}

fn view(app: &App, model: &Model, frame: Frame) {
    let draw = example_draw(app);

    if model.svg_render_frame == app.elapsed_frames() {
        nannou::draw::renderer::svg::render_and_save(
            app.main_window().rect(),
            &draw.clone(),
            captured_frame_path(app),
        );
    } else {
        draw.to_frame(app, &frame).unwrap();
    }
}

fn captured_frame_path(app: &App) -> std::path::PathBuf {
    std::path::PathBuf::from(env!("CARGO_MANIFEST_DIR"))
        .join(format!("out_{:03}.svg", app.elapsed_frames()))
}

fn example_draw(app: &App) -> Draw {
    // Begin drawing
    let draw = app.draw();

    // Clear the background to blue.
    draw.background().color(CORNFLOWERBLUE);

    // Draw a purple triangle in the top left half of the window.
    let win = app.window_rect();
    draw.tri()
        .points(win.bottom_left(), win.top_left(), win.top_right())
        .color(VIOLET);

    // Draw an ellipse to follow the mouse.
    let t = app.time;
    draw.ellipse()
        .x_y(app.mouse.x * t.cos(), app.mouse.y)
        .radius(win.w() * 0.125 * t.sin())
        .color(RED);

    // Draw a line!
    draw.line()
        .weight(10.0 + (t.sin() * 0.5 + 0.5) * 90.0)
        .caps_round()
        .color(PALEGOLDENROD)
        .points(win.top_left() * t.sin(), win.bottom_right() * t.cos());

    // Draw a quad that follows the inverse of the ellipse.
    draw.quad()
        .x_y(-app.mouse.x, app.mouse.y)
        .color(DARKGREEN)
        .rotate(t);

    // Draw a rect that follows a different inverse of the ellipse.
    draw.rect()
        .x_y(app.mouse.y, app.mouse.x)
        .w(app.mouse.x * 0.25)
        .hsv(t, 1.0, 1.0);

    draw
}