Skip to main content

​
Origin Point and Y-Axis

In PDF, traditionally the origin (0, 0) of a page is located at its bottom-left point. However, in MuPDF WebViewer, the origin (0, 0) of a page is located at its top-left point as this is more suited for web environments and digital displays. WebViewer Coordinate system
This is also known as User space versus Device space

​
Point Size

Coordinates are float numbers and measured in points, where:
  • one point equals 1/72 inches.
Typical document page sizes are ISO A4 and Letter. A Letter page has a size of 8.5 x 11 inches, corresponding to 612 x 792 points. Now we know our document size the MuPDF coordinate system for the bottom right would be coordinate (612, 792).

​
Point Precision

Theoretically, there are infinitely many coordinate positions on a PDF page. In practice however, at most the first 5 decimal places are sufficient for a reasonable precision.
⌘I