Re: Trying to figure out some rasterization problems
Behdad Esfahbod <[email protected]>
| Newsgroups | gmane.comp.lib.cairo |
|---|---|
| Message-ID | <[email protected]> |
On 13-04-21 11:13 AM, David Kastrup wrote: >>> >> Unfortunately, it _does_ make a difference. Why do we care? Because >>> >> note stems are rectangles with rounded corners. Not completely circular >>> >> stroke ends, just rounded corners. If we care for stroke adjustment >>> >> (which we do), that means our actual shape needs to be represented as an >>> >> intersection of a stroke-adjusted rectangle and clipping off the rounded >>> >> corners. That clipping apparently removes too much. An easy solution >>> >> appears to be to restroke the middle part of the rectangle without any >>> >> clipping. Which comes to problem b) which I think Cairo might be >>> >> responsible for: >> > >> > I still have no idea what you are talking about. Perhaps some images >> > would help? > What's wrong with "a rectangle with rounded corners"? At any rate, > stroke adjustment deals with rasterization on a black&white device: if > you have a thin line, the normal PostScript/PDF way is to color all > pixels black that have any part inside covered by the filled/stroked > region. For thin lines, this adds up to one line of blackness too much > on each side. Stroke adjustment checks the total width and reduces it > (starting on the side with the larger overhang) by 1 pixel until it is > not off more than half a pixel. So 0, 1 or two pixels are culled from > the width, depending on where it lies in the rasterization. Ok, it makes more sense now. But I have to ask: in 2013, who cares about stroke adjustment? Just draw a shape and fill it. I'm sure no print would look bad. -- behdad http://behdad.org/ -- cairo mailing list [email protected] http://lists.cairographics.org/mailman/listinfo/cairo