printpdf

printpdf is a library designed for creating printable PDF documents.

[dependencies]
printpdf = "0.3.2"

Features

Currently, printpdf can only write documents, not read them.

Page generation
Layers (Illustrator like layers)
Graphics (lines, shapes, bezier curves)
Images (currently BMP only or generate your own images)
Embedded fonts (TTF and OTF) with Unicode support
Advanced graphics - overprint control, blending modes, etc.
Advanced typography - character scaling, character spacing, superscript, subscript, outlining, etc.
PDF layers (you should be able to open the PDF in Illustrator and have the layers appear)

Getting started

Writing PDF

Simple page

use printpdf::*;
use std::fs::File;
use std::io::BufWriter;

let (doc, page1, layer1) = PdfDocument::new("PDF_Document_title", Mm(247.0), Mm(210.0), "Layer 1");
let (page2, layer1) = doc.add_page(Mm(10.0), Mm(250.0),"Page 2, Layer 1");

doc.save(&mut BufWriter::new(File::create("test_working.pdf").unwrap())).unwrap();

Adding graphical shapes

use printpdf::*;
use std::fs::File;
use std::io::BufWriter;
use std::iter::FromIterator;

let (doc, page1, layer1) = PdfDocument::new("printpdf graphics test", Mm(297.0), Mm(210.0), "Layer 1");
let current_layer = doc.get_page(page1).get_layer(layer1);

// Quadratic shape. The "false" determines if the next (following)
// point is a bezier handle (for curves)
// If you want holes, simply reorder the winding of the points to be
// counterclockwise instead of clockwise.
let points1 = vec![(Point::new(Mm(100.0), Mm(100.0)), false),
                   (Point::new(Mm(100.0), Mm(200.0)), false),
                   (Point::new(Mm(300.0), Mm(200.0)), false),
                   (Point::new(Mm(300.0), Mm(100.0)), false)];

// Is the shape stroked? Is the shape closed? Is the shape filled?
let line1 = Line {
    points: points1,
    is_closed: true,
    has_fill: true,
    has_stroke: true,
    is_clipping_path: false,
};

// Triangle shape
// Note: Line is invisible by default, the previous method of
// constructing a line is recommended!
let mut line2 = Line::from_iter(vec![
    (Point::new(Mm(150.0), Mm(150.0)), false),
    (Point::new(Mm(150.0), Mm(250.0)), false),
    (Point::new(Mm(350.0), Mm(250.0)), false)]);

line2.set_stroke(true);
line2.set_closed(false);
line2.set_fill(false);
line2.set_as_clipping_path(false);

let fill_color = Color::Cmyk(Cmyk::new(0.0, 0.23, 0.0, 0.0, None));
let outline_color = Color::Rgb(Rgb::new(0.75, 1.0, 0.64, None));
let mut dash_pattern = LineDashPattern::default();
dash_pattern.dash_1 = Some(20);

current_layer.set_fill_color(fill_color);
current_layer.set_outline_color(outline_color);
current_layer.set_outline_thickness(10.0);

// Draw first line
current_layer.add_shape(line1);

let fill_color_2 = Color::Cmyk(Cmyk::new(0.0, 0.0, 0.0, 0.0, None));
let outline_color_2 = Color::Greyscale(Greyscale::new(0.45, None));

// More advanced graphical options
current_layer.set_overprint_stroke(true);
current_layer.set_blend_mode(BlendMode::Seperable(SeperableBlendMode::Multiply));
current_layer.set_line_dash_pattern(dash_pattern);
current_layer.set_line_cap_style(LineCapStyle::Round);

current_layer.set_fill_color(fill_color_2);
current_layer.set_outline_color(outline_color_2);
current_layer.set_outline_thickness(15.0);

// draw second line
current_layer.add_shape(line2);

Adding images

Note: Images only get compressed in release mode. You might get huge PDFs (6 or more MB) in debug mode. In release mode, the compression makes these files much smaller (~ 100 - 200 KB).

To make this process faster, use BufReader instead of directly reading from the file. Images are currently not a top priority.

Scaling of images is implicitly done to fit one pixel = one dot at 300 dpi.

extern crate printpdf;

// imports the `image` library with the exact version that we are using
use printpdf::*;

use std::convert::From;
use std::fs::File;

fn main() {
    let (doc, page1, layer1) = PdfDocument::new("PDF_Document_title", Mm(247.0), Mm(210.0), "Layer 1");
    let current_layer = doc.get_page(page1).get_layer(layer1);

    // currently, the only reliable file format is bmp (jpeg works, but not in release mode)
    // this is an issue of the image library, not a fault of printpdf
    let mut image_file = File::open("assets/img/BMP_test.bmp").unwrap();
    let image = Image::try_from(image::bmp::BmpDecoder::new(&mut image_file).unwrap()).unwrap();

    // translate x, translate y, rotate, scale x, scale y
    // by default, an image is optimized to 300 DPI (if scale is None)
    // rotations and translations are always in relation to the lower left corner
    image.add_to_layer(current_layer.clone(), None, None, None, None, None, None);

    // you can also construct images manually from your data:
    let mut image_file_2 = ImageXObject {
        width: Px(200),
        height: Px(200),
        color_space: ColorSpace::Greyscale,
        bits_per_component: ColorBits::Bit8,
        interpolate: true,
        /* put your bytes here. Make sure the total number of bytes =
           width * height * (bytes per component * number of components)
           (e.g. 2 (bytes) x 3 (colors) for RGB 16bit) */
        image_data: Vec::new(),
        image_filter: None, /* does not work yet */
        clipping_bbox: None, /* doesn't work either, untested */
    };

    let image2 = Image::from(image_file_2);
}

Adding fonts

Note: Fonts are shared between pages. This means that they are added to the document first and then a reference to this one object can be passed to multiple pages. This is different to images, for example, which can only be used once on the page they are created on (since that's the most common use-case).

use printpdf::*;
use std::fs::File;

let (doc, page1, layer1) = PdfDocument::new("PDF_Document_title", Mm(247.0), Mm(210.0), "Layer 1");
let current_layer = doc.get_page(page1).get_layer(layer1);

let text = "Lorem ipsum";
let text2 = "unicode: стуфхfцчшщъыьэюя";

let font = doc.add_external_font(File::open("assets/fonts/RobotoMedium.ttf").unwrap()).unwrap();
let font2 = doc.add_external_font(File::open("assets/fonts/RobotoMedium.ttf").unwrap()).unwrap();

// text, font size, x from left edge, y from bottom edge, font
current_layer.use_text(text, 48, Mm(200.0), Mm(200.0), &font);

// For more complex layout of text, you can use functions
// defined on the PdfLayerReference
// Make sure to wrap your commands
// in a `begin_text_section()` and `end_text_section()` wrapper
current_layer.begin_text_section();

    // setup the general fonts.
    // see the docs for these functions for details
    current_layer.set_font(&font2, 33);
    current_layer.set_text_cursor(Mm(10.0), Mm(10.0));
    current_layer.set_line_height(33);
    current_layer.set_word_spacing(3000);
    current_layer.set_character_spacing(10);
    current_layer.set_text_rendering_mode(TextRenderingMode::Stroke);

    // write two lines (one line break)
    current_layer.write_text(text.clone(), &font2);
    current_layer.add_line_break();
    current_layer.write_text(text2.clone(), &font2);
    current_layer.add_line_break();

    // write one line, but write text2 in superscript
    current_layer.write_text(text.clone(), &font2);
    current_layer.set_line_offset(10);
    current_layer.write_text(text2.clone(), &font2);

current_layer.end_text_section();

Optimiziation

Minimizing the size of generated PDFs

By default, the PDF adherese to a "PDF conformance level", usually the PDF-X 1.4 Standard. This means that the PDF includes a full ICC profile file (which is around 500KB large). To turn it off, see the no_icc example:

let (mut doc, _page1, _layer1) = PdfDocument::new("printpdf no_icc test", Mm(297.0), Mm(210.0), "Layer 1");
doc = doc.with_conformance(PdfConformance::Custom(CustomPdfConformance {
  requires_icc_profile: false,
  requires_xmp_metadata: false,
    .. Default::default()
}));

In debug mode, the images, streams and fonts are not compressed for easier debugging. Try building in release mode to optimize the size further.

Changelog

See the CHANGELOG.md file.

Goals and Roadmap

The goal of printpdf is to be a general-use PDF library, such as libharu or similar. PDFs generated by printpdf should always adhere to a PDF standard, except if you turn it off. Currently, only the standard PDF/X-3:2002 is covered (i.e. valid PDF according to Adobe Acrobat). Over time, there will be more standards supported. Checking a PDF for errors is currently only a stub.

Planned features / Not done yet

The following features aren't implemented yet, most

Clipping
Aligning / layouting text
Open Prepress Interface
Halftoning images, Gradients, Patterns
SVG / instantiated content
Forms, annotations
Bookmarks / Table of contents
Conformance / error checking for various PDF standards
Embedded Javascript
Reading PDF
Completion of printpdf wiki

Testing

Currently the testing is pretty much non-existent, because PDF is very hard to test. This should change over time: Testing should be done in two stages. First, test the individual PDF objects, if the conversion into a PDF object is done correctly. The second stage is manual inspection of PDF objects via Adobe Preflight.

Put the tests of the first stage in /tests/mod.rs. The second stage tests are better to be handled inside the plugins' mod.rs file. printpdf depends highly on lopdf, so you can either construct your test object against a real type or a debug string of your serialized type. Either way is fine - you just have to check that the test object is conform to what PDF expects.