Expected behavior of dashes, lines and patterns under transform
cu <[email protected]>
| Newsgroups | gmane.comp.lib.cairo |
|---|---|
| Message-ID | <[email protected]> |
I've been trying to draw into Cairo context with transform matrix set. Under scaling transform (with scaling factor of, say, 1000 with small coordinate values supplied to drawing functions which then scale them up to user level pixel coordinates) I've seen the following: 1. Line widths seem to be scaled up (which is counter-intuitive) 2. Even if transform is set before drawing and reset to identity before setting line width, lines don't look quite the same as if scaled coordinates are used as input - anialiasing is relatively poor. 3. Can't tell for sure what happens with dashes - they seem not to work half the time (endless loops, perhaps the new release takes care of that). It seems that dash lengths are scaled as well. Resetting to identity before drawing dashed lines helps somewhat, but dash lengths still appear "off" (different from drawing with pre-scaled coordinates). 4. I was unable to draw a source "sprite" pattern onto a scaled surface, no matter what combination of scaling/resetting to identity/moving etc. I tried. How much of that is expected behavior? Is there a document that describes in more detail what the expected behavior of dashes, lines/widths and patterns (i.e. other images used as "sprites") under transform should be? -- cairo mailing list [email protected] http://lists.cairographics.org/mailman/listinfo/cairo