[cairo] cairo design

Bill Spitzak spitzak at d2.com
Fri Apr 23 16:31:21 PDT 2004

On Friday 23 April 2004 01:46 pm, Keith Packard wrote:
> The default cairo transformation matrix sets the user coordinate space to
> approximately 100dpi.  For most displays, this ends up being an identity
> transformation, but higher resolution devices will end up using
> non-identity default transformations.

It actually picks the nearest integer transform to 1/96, right? If displays 
go higher resolution you will get a 2:1 transformation, but you will never 
get a non-integer one. This is quite a good idea, as it is approximately 
resolution-independent without messing up programs that assumme things about 
the pixel layout.

You can also directly set the transform so one unit is an actual dimension 
(1/72 inch?) and scale from there to any other actual dimension.

                   ,~,~,~,~ ~ ~ ~ ~
     /\_       _|_========___         Bill Spitzak
 ~~~/\/\\~~~~~~\____________/~~~~~~~~ spitzak at d2.com

More information about the cairo mailing list