2.0 Pixel Printing

Compatibility

• ✅ 2.0 | ⛔ 1.9 | ...

Background

These features may not work with many raw printing devices, such as Zebra, Epson, Citizen printers. The data is sent in Pixel Printing format, which is more common for LaserJet or Deskjet printers. The ZDesigner driver from Zebra allows both raw and pixel printing.

To test these features without a physical printer, try using a PDF or XPS writer.

Contents

The following code can be used for Pixel Printing (formerly Postscript Printing) only. If you are unsure what Pixel Printing is, please refer to What is Pixel Printing?

• HTML Printing
• PDF Printing
• Image Printing
• Advanced Pixel Printing

---

HTML Printing

1. HTML rendering is done via pure Java in using an embedded webkit browser

   var config = qz.configs.create("Printer Name");
   var data = [
       {
           type: 'html',
           format: 'file',
           data: 'assets/html_sample.html'
       }
   ];
   qz.print(config, data).catch(function(e) { console.error(e); });

2. An options parameter can be supplied to to signify things including margins, orientation, size, printer language, encoding, etc.

   var config = qz.configs.create("Printer Name");
   var data = [
       {
           type: 'html',
           format: 'plain',
           data: 'assets/html_sample.html',
           options: { margins: 2, orientation: 'landscape', printerTray: 2 }
       }
   ];
   qz.print(config, data).catch(function(e) { console.error(e); });

   JavaFX

   • ⚠️ Java 8 + JavaFX is required for high-resolution (>72 dpi) HTML printing.
   • ⚠️ By default, JavaFX is NOT included in OpenJDK
     • 💡 Older Ubuntu versions can get Oracle Java 8 + JavaFX here: http://www.webupd8.org/2012/09/install-oracle-java-8-in-ubuntu-via-ppa.html

PDF Printing

QZ Tray 2.0 allows printing PDF files directly to a printer using Apache PDFBOX.

• ⚠️ Warning: Mac users may need to specify a density per #155

1. How to print a PDF file

   var config = qz.configs.create("Printer Name");
   var data = [
      { 
         type: 'pdf', 
         data: 'assets/pdf_sample.pdf' 
      }
   ];
   qz.print(config, data).catch(function(e) { console.error(e); });

2. How to print a base64 PDF

   var config = qz.configs.create("Printer Name");
   var data = [
      { 
         type: 'pdf',
         format: 'base64',
         data: 'Ck4KcTYwOQpRMjAzLDI2CkI1LDI2LDAsMUEsMyw3LDE1MixCLCIxMjM0IgpBMzEwLDI2LDAsMywx...' 
      }
   ];
   qz.print(config, data).catch(function(e) { console.error(e); });

Image Printing

var config = qz.configs.create("Printer Name");
var data = [
   { 
      type: 'image', 
      data: 'assets/img/image_sample.png' 
   }
];
qz.print(config, data).catch(function(e) { console.error(e); });

Advanced Printing

Page Size

A page size can be set using the config parameter size.

Custom page sizes are not supported. When a page size is set, the closest matching page size available to the printer (determined by the printer driver) is selected.

• To print to the wider edge (standard page sizes are expected), the orientation parameter can be used to set orientation to landscape
• Both standard and metric sizes are supported, but it is highly recommended to use inches (standard). This is do to the density that is in DPI (dots per inch).

function printStuff() {
   var config = qz.configs.create("Printer Name", { units: "in", orientation: "landscape", size: { width: 2, height: 5} )};

   var data = [
      'Raw Data\n',
      'More Raw Data\n',
      'Even More Raw Data\n'
   ];

   qz.print(config, data).catch(function(e) { console.error(e); });
}

Image Interpolation

A config parameter interpolation can be provided to change the pixel blending technique used when scaling an image.

var config = qz.configs.create("Printer Name", { interpolation: "nearest-neighbor" });
var data = [
   { 
      type: 'image', 
      data: 'assets/img/image_sample.png' 
   }
];
qz.print(config, data).catch(function(e) { console.error(e); });

Density

Not providing a density will cause printing to use the default value for the printer. A config parameter density can be provided to change the DPI, dots/mm or dots/cm respectively.

var config = qz.configs.create("Printer Name", { units: "in", density: "600" });  // force 600dpi
var data = [
   { 
      type: 'pdf', 
      data: 'assets/pdf_sample.pdf' 
   }
];
qz.print(config, data).catch(function(e) { console.error(e); });

Custom Job Name

A config parameter jobName can be provided to change the name listed in the print queue.

var config = qz.configs.create("Printer Name", { jobName: "Receipt #123456" });
var data = [
   { 
      type: 'image', 
      data: 'assets/img/image_sample.png' 
   }
];
qz.print(config, data).catch(function(e) { console.error(e); });