Cutting out parts of a pattern. Which tool/technique should I use

[DanC]

I've been working on this all day.  Unfortunately, I'm new(ish) to inkscape so I don't know what tool or technique to use.  I've attached the drawing.

To describe the problem simply - start with a radial line that is cloned and rotated around one end to create a starburst pattern.  Then create a circle that surrounds the pattern, then several increasingly smaller circles towards the center, creating a series of rings.  Now, the problem is that I want some of the rings to show the full starburst pattern below it, but other rings to have only 4 or 5 of the lines show through.  Basically, they alternate.

If you look at the drawing, it's a calendar.  The outer two rings should show each of the radial lines separating the days, but the ring that contains the names of the months should only show the lines between the two months.  Similarly for the seasons, there should be only 4 lines between the seasons. 

For most of the day I've played around with trying to create the effect I'm looking for by playing with layers, object order and transparency, but since the rings are actually circles, once an outer ring is set to fill and not be opaque, it will obscure all rings below it.

So I'm not sure exactly what technique I should use.  It seems like some sort of clipping might be the answer.  If I can figure out how to convert my two circle objects into just the ring created by the difference between the two then use that to clip?  As you can see, this is where I get lost.  If you know how to do this please tell me what you would do.

Thank you.

[brynn]

Welcome to the forum!

I do things like this all the time, so I can give you some ideas.  Unfortunately, I have to attend a meeting in a few minutes.  But I'll get back to you in something like 3 hours.

[brynn]

Ok, the easiest way would be to simply cover up what you don't want to see, with an object the same color as your background.  If bg is transparent, that won't work.  Plus, I would strongly suggest not using this technique anyway.

Also, note there there will be a few different ways to approach this, and sometimes the choice comes down simply to personal preference.

The first thing that comes to mind for me, is to make 2 or 3 different, compound paths.  However many different paths you need, and have  them broken in different places, where you don't want the radial line to show.  You can still use clones.  The way I read your message, you'll need 3 of these paths, although I might have missed a detail here or there.  Might need one or 2 more?

You could convert all the clones to paths, and edit them in place as them sit now.  Or you could start a 2nd version beside this one (or maybe in another file, if necessary), create the specific compound paths, and recreate the radial array.

Or the idea which it seems you were working on, maybe making an opaque ring, or a ring with opaque spaces, to cover up the paths.  That would work, only if the final version of this isn't going to have a transparent background.  If you want it transparent, the only way to do it would be to edit the paths.

I can give you some tips on either way.  I just hesitate to elaborate until I know which one to focus on.

And by the way, really nice work on that.  I like it quite a lot!  Oh and also, I'm not sure if you're aware, but it looks like you've been working at 35% zoom - meaning the the image is much larger than you realize.

It would take a lot of work, and I'm not sure if the outcome would be an improvement.  But if each radial ray could come to a point in the middle, you might avoid that darkening effect in the middle.  Oh!  Or an easier way might be to give the stroke a gradient, so that the middle isn't as dark.  Although I think it's interesting how you used that darkening effect and made the year characters white instead of black.

OH!  Come to think of it, you could create a custom gradient for the strokes of the radial rays to accomplish your main goal.  That would be easier than either of the suggestions I had!!  And probably 3 or 4 gradients would be needed.

Anyway, let me know which way you want to go, and whatever specific info you might need.

[DanC]

All of those are great ideas and most of them I never thought of.  I'm definitely going to play around with the gradients to see what effect I can create.

I think the thing that makes the most sense to me is trying to create objects out of the "rings" instead of the elipses.  In other words, what our eye is perceiving as a ring is really two circle objects of different sizes, the smaller on top.  If I had an object that was just the difference between the two circles then I think I could achieve it with simple stacking.  I'm not sure I'm explaining what I mean clearly, but basically what I'm saying is the problem that I'm having is because my objects are complete circles and the visual space I'm trying to show isn't.

Yes, the drawing is large.  I successfully did this a few years ago, I just don't remember how.  Attached is the 2012 version.  It is a poster-sized calendar that hangs on the wall.

EDIT: omg, I think it's as simple as dragging two circles to the side, centering them and then pressing ctrl-  !!

[DanC]

oops! (attached)

[DanC]

Learning how to make the rings helped, but it's perhaps not the complete solution that I thought it was.  I think the best solution is the suggestion you had of breaking the radial lines into individual objects (paths?) where they intersect the circles.  Then I can delete sections of them at will.  Repetitive but easiest perhaps. 

[DanC]

I'm just going to start over from scratch.  I'll learn more that way anyway. 

[brynn]

If it were me, I'd make some special gradients.  I'll make an SVG file....  Oh no, I'll just use yours, and I'll make a gradient to show you. 

For the gradients, to make that idea work, there will need to be 2 gradient stops, pretty much right on top of each other.  (I'm not sure technically if they are on top of each other, but they are as close as they can get.  When you drag one gradient stop towards another, it won't go past the next stop.  That's how they have to be, to go from 100% opaque to 100% transparent.)  The reason I would use gradients, is because I wouldn't have to start almost all over.  But I'm like you I guess - I like to learn new things!  I'll use March to demonstrate how a gradient would work.

For the rings, Difference is one way to do it.  Another way is to select both circles and do Path menu > Combine (or whatever the key shortcut is).

For breaking the paths in certain areas, you can use the existing image to create them.  Start by selecting the inner and outer circles for the month ring. 

 -- Path menu > Combine
 -- remove the fill

Let's use the 9 o'clock ray.  Select it, and click the button to break the clone's connection to its parent (makes it a path).

 -- select the ring with Selection tool
 -- move it on top of the ray path  ( )
 -- select both the ring and the ray path
 -- Path menu > Cut Path   (Note that the month names go wacky at this point - not sure why at the moment, but just ignore it for now)  (or else duplicate the ring, and use the duplicate)

The ring will disappear here (although if you used a duplicate, the original will still be there), and now the ray path is in 3 pieces.  After you deselect everything, you can select only the piece you need to remove, and delete it.  Now, that ray, with the missing month section, can be used for all the months.  And you can make different rays according to how many places you need open spaces.

[DanC]

I took a look at what you did and the gradient works great.  Unfortunately I already went a different route and broke each of the lines into paths.  I tried the technique of using the ring to cut the ray, but I couldn't get it to work (I don't think it does) with multiple rays and multiple rings at once.  So in the end I enabled snapping to path intersection and then using the path tool to double-click and add nodes at each intersection that I wanted to snip.  Then I used the "delete segment between nodes" button on the path toolbar.  I did this 360 times. 

Here is the latest version.  I've replaced the year in the center with a sun image because the calendar actually works for different years since there are no days of the week indicated.  If I decide to go back to having the year in the center I can because the center radials are still there, just hidden beneath the center ellipse. 

Thank you VERY much for your help.  You helped push me past the "this stuff is impossible" stage.  Feel free to use the drawing in any way you wish.

Dan

[brynn]

I did this 360 times.

Yikes! 

The reason I only did it to one path, is because I thought you were going to construct it in the same way you reported originally.  I think you said you cloned the path and rotated each one around. 

On yeah, I see you actually made a few changes from the original.  Well, it works for any year except for Leap Year.

Hhmm, I'm just trying to think of some way to add the days of the week.  You could add another ring for it, but you'd still have to edit every year, to rotate that ring.  So if this were going to be printed like on a poster or something, it wouldn't work to put the days of the week on it.

.....Well....not unless the poster had a moving part.  If there were a way to add a moving part to it, so that you could rotate that ring every year.....that might be pretty cool!  Like maybe if you mounted it to something more substantial than just paper - cardboard or even....what's that called that they make model airplaines with -- balsa?  Something like that could work.

And instead of having the movable ring on top, I think I'd make like little windows in the main part of the calendar, and then the ring can rotate behind, with the days of the week showing through the little windows.

Well anyway, just daydreaming!

I'm glad you got it worked out and you're happy with the results