Re: [Gimp-user] Circular arcs in paths
Hi, Joao S. O. Bueno Calligaris [EMAIL PROTECTED] writes: If you will be needing two or three bezier points only, tell me, and point me to such a page, I can work a python script for doing that. I just added a new PDB function to CVS that will simplify this a lot. Basically you can now say gimp_path_import_string (?xml?svgellipse rx='100' ry='100'//svg, -1, FALSE, FALSE); and don't have to fiddle with the details of getting the bezier points right. We still need a better PDB API for vectors though. Someone needs to motivate Simon... Sven ___ Gimp-user mailing list Gimp-user@lists.xcf.berkeley.edu http://lists.xcf.berkeley.edu/mailman/listinfo/gimp-user
Re: [Gimp-user] Circular arcs in paths
Can anyone tell me if there is a straightforward way to make a circular path? You could use the Elliptical Select Tool (hold Shift down to get a perfect circle). Then convert your selection to a path (Rightclick on Image - Select - To Path) Andreas ___ Gimp-user mailing list Gimp-user@lists.xcf.berkeley.edu http://lists.xcf.berkeley.edu/mailman/listinfo/gimp-user
Re: [Gimp-user] Circular arcs in paths
On Wed, Mar 02, 2005 at 07:19:03PM +0100, Andreas Waechter wrote: Can anyone tell me if there is a straightforward way to make a circular path? You could use the Elliptical Select Tool (hold Shift down to get a perfect circle). Then convert your selection to a path (Rightclick on Image - Select - To Path) Yes, but at smaller sizes this results in a bad lumpy circle. Presumably elliptical-select is drawing a pixellated circle, and then selection-to-path is approximating that pixellated shape with the path. The results aren't even symmetric! Try it with a diameter under 50 pixels, and then stroke the path with a 1-pixel line, and then look closely-- you can see that it's oddly shaped and asymmetric left-to-right. To me this demonstrates a need for one of two things: 1. A way to add elliptic arcs to paths 2. A simple way to constrain the bezier curves to very precise approximations of circular arcs (and/or elliptic arcs). ___ Gimp-user mailing list Gimp-user@lists.xcf.berkeley.edu http://lists.xcf.berkeley.edu/mailman/listinfo/gimp-user
Re: [Gimp-user] Circular arcs in paths
Hi, Eric Seppanen [EMAIL PROTECTED] writes: Can anyone tell me if there is a straightforward way to make a circular path? Or alternatively, how can I can come as close as possible to a circular arc with the bezier path tool? Positioning the handles by eye doesn't seem very accurate or reliable. There are lots of webpages with pages of math on how to approximate circular arcs using bezier curves, but nothing practical. Either use the elliptical selection tool and convert the selection to a path or import a simple SVG that says something like: svg ellipse rx=100 ry=100/ /svg Sven ___ Gimp-user mailing list Gimp-user@lists.xcf.berkeley.edu http://lists.xcf.berkeley.edu/mailman/listinfo/gimp-user
Re: [Gimp-user] Circular arcs in paths
Hi, Eric Seppanen [EMAIL PROTECTED] writes: Yes, but at smaller sizes this results in a bad lumpy circle. Presumably elliptical-select is drawing a pixellated circle, and then selection-to-path is approximating that pixellated shape with the path. It's a known problem of the selection to path conversion that the source is a mask, and thus bound to pixels. You can get better results by tuning the selection to path conversion (Shift-Click the button in the Paths dialog). To me this demonstrates a need for one of two things: 1. A way to add elliptic arcs to paths 2. A simple way to constrain the bezier curves to very precise approximations of circular arcs (and/or elliptic arcs). Basically what's needed is a tool to create basic shapes. Internally most of the infrastructure needed for this is already available, including functions to generate perfect circular paths (as you may probably already have found out from the SVG example). Sven ___ Gimp-user mailing list Gimp-user@lists.xcf.berkeley.edu http://lists.xcf.berkeley.edu/mailman/listinfo/gimp-user
Re: [Gimp-user] Circular arcs in paths
Yes, but at smaller sizes this results in a bad lumpy circle. Presumably elliptical-select is drawing a pixellated circle, and then selection-to-path is approximating that pixellated shape with the path. Another solution (maybe easyer) could be : 1. Create a big circular selection 2. Selection - path 3. Resize this path to get it as small as you want (using the usual layer/selection/path resize tool). PA. Découvrez le nouveau Yahoo! Mail : 250 Mo d'espace de stockage pour vos mails ! Créez votre Yahoo! Mail sur http://fr.mail.yahoo.com/ ___ Gimp-user mailing list Gimp-user@lists.xcf.berkeley.edu http://lists.xcf.berkeley.edu/mailman/listinfo/gimp-user
Re: [Gimp-user] Circular arcs in paths
On Wednesday 02 March 2005 14:39, Eric Seppanen wrote: Hello, Can anyone tell me if there is a straightforward way to make a circular path? Or alternatively, how can I can come as close as possible to a circular arc with the bezier path tool? Positioning the handles by eye doesn't seem very accurate or reliable. There are lots of webpages with pages of math on how to approximate circular arcs using bezier curves, but nothing practical. Hmmmake a circular selection, and selection-path ? That creates a few more points than are needed, but it is fine for what I do. If you will be needing two or three bezier points only, tell me, and point me to such a page, I can work a python script for doing that. Regards, JS -- Thanks, Eric ___ Gimp-user mailing list Gimp-user@lists.xcf.berkeley.edu http://lists.xcf.berkeley.edu/mailman/listinfo/gimp-user ___ Gimp-user mailing list Gimp-user@lists.xcf.berkeley.edu http://lists.xcf.berkeley.edu/mailman/listinfo/gimp-user
