Bug 696819

Summary: Subpixel rendering
Product: MuPDF Reporter: ecir.hana
Component: fitzAssignee: MuPDF bugs <mupdf-bugs>
Status: RESOLVED WONTFIX    
Severity: normal CC: robin.watts
Priority: P4    
Version: unspecified   
Hardware: PC   
OS: All   
Customer: Word Size: ---

Description ecir.hana 2016-06-04 00:04:57 UTC 
Introduction:
Subpixel rendering is a way of rasterizing curved shapes that takes advantage of the pixel RGB stripes arrangement on the screen:
https://en.wikipedia.org/wiki/Subpixel_rendering

Synopsis:
It would be great if MuPDF supported the subpixel rendering of text as it makes the text appear sharper and hence more pleasant to read.

References:
http://askubuntu.com/questions/45255/why-isnt-document-viewer-2-32-0-using-subpixel-rendering
http://askubuntu.com/questions/778852/pdf-viewer-with-subpixel-rendering
Comment 1 Robin Watts 2016-06-06 06:25:04 UTC 
In order to support subpixel rendering, we need to know the layout of the sub-pixels on the screen.

Most computer monitors are RGBRGBRGB, though some are BGRBGRBGR.

Many devices have more complex layouts (with certain subpixels shared between pixels). For handheld devices this is even harder to get right due to the need to support different rotations.

We therefore take the view that if you want subpixel rendering, you should update the transform on input to be 3 times as wide, render to a wider pixmap, and then filter it down according to your own specific devices screen.

The core is entirely capable of doing this with no extra changes required on our part.