<html> <head> <style></style> </head> <body class='hmmessage'> > Date: Fri, 27 Aug 2010 14:46:03 +0200 > Subject: Re: [cairo] Changing line color > From: mkbosmans@gmail.com > To: opustenom@hotmail.com > CC: cairo@cairographics.org > > 2010/8/27 necko necko <opustenom@hotmail.com>: > > In order for my pdf file to look nicer, I changed the background to black, > > and now > > I need to emphasize a number of lines between certain coordinates. Some > > lines need > > to be shown as red, some as green, and some as blue, or a variation. > > I tested the above requirement with the code below: > >   cairo_set_line_width (cr, .5); > >   cairo_set_source_rgb(cr, 1, 0, 0); > >   cairo_move_to (cr, 152.84, -50.0); > >   cairo_line_to (cr, 83.97, 30.93); > >   cairo_stroke_preserve(cr); > > > >   cairo_set_source_rgb(cr, 0, 0, 1); > >   cairo_move_to(cr, 90, 1); > >   cairo_line_to(cr, 40, 1); > >   cairo_stroke_preserve(cr); > > ...................................... > > However, both lines are displayed as blue, with a very thin red line in the > > middle of it. > > Is there a way to specify that one line needs to be only blue, and the other > > only red? > > What would be the code to try? > > I appreciate your help. > > You'll want to user cairo_stroke instead of cairo_stroke_preserve. > Because in the code above the second path from the blue line gets > added to the already exisiting path you used for the red line, thus > rendering the two lines on top of eachother. > > Maarten Thank you, Maarten. In addition, is there some other way to change the background of the pdf file, instead of specifying the bounding rectangle  and then invoking fill()? </body> </html>