artano 0.3.13

Adds text to pictures.
Documentation 
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use image::{GenericImage, GenericImageView, Pixel};
use imageproc::definitions::Clamp;
use rusttype::{self, Font, Scale};

pub fn text<'a, I>(
    image: &'a mut I,
    color: I::Pixel,
    x: u32,
    y: u32,
    scale: Scale,
    font: &'a Font<'a>,
    text: &'a str,
) where
    I: GenericImage + GenericImageView,
    <<I as GenericImageView>::Pixel as Pixel>::Subpixel: Into<f32> + Clamp<f32>,
{
    use imageproc::pixelops;

    let v_metrics = font.v_metrics(scale);
    let offset = rusttype::point(0.0, v_metrics.ascent);

    for glyph in font.layout(text, scale, offset) {
        if let Some(bb) = glyph.pixel_bounding_box() {
            glyph.draw(|gx, gy, gv| {
                let gx = gx as i32 + bb.min.x;
                let gy = gy as i32 + bb.min.y;

                let image_x = gx + x as i32;
                let image_y = gy + y as i32;

                let image_width = image.width() as i32;
                let image_height = image.height() as i32;

                if image_x >= 0 && image_x < image_width && image_y >= 0 && image_y < image_height {
                    let pixel = image.get_pixel(image_x as u32, image_y as u32);
                    let weighted_color = pixelops::weighted_sum(pixel, color, 1.0 - gv, gv);
                    image.put_pixel(image_x as u32, image_y as u32, weighted_color);
                }
            })
        }
    }
}