Cutting up a shape

JCook · Post by **JCook** » Mon Mar 17, 2008 2:19 pm

Is there a way to cut a shape into two parts?

I want to start with one shape, and then have the end of that shape split so that the split part separates and moves away, leaving the rest of the shape intact, but with the same jagged edge as the part that split off. It's an ice shelf, and I need to make chunks split off from it. I was thinking that there might be a knife tool, or some script that could help with this, but I haven't found one. Any ideas?

thanks,
Jack

KenW · Post by **KenW** » Mon Mar 17, 2008 2:42 pm

Perhaps your hope is similar to this script request - viewtopic.php?t=3071

slowtiger · Post by **slowtiger** » Mon Mar 17, 2008 2:50 pm

There's no knife tool. However, it's not so difficult to create two shapes with exactly fitting edges.

Draw shape #1 with a nice zigzagged edge. Copy that shape and paste it besides the first one. Now select all points of shape #2 except the zigzagged ones and drag them over the zigzagged part of the outline, then flip that selection and maybe rotate it. Adjust the corners. With the right choice of fill and outline colour you'll get two shapes which look like one.

Genete · Post by **Genete** » Mon Mar 17, 2008 2:58 pm

I think the only way to make it possible is have the parts already as separated shapes.
Maintain them together linking each shape to a bone and play with bones positions (rotations too) to perform the broke animation. You can also use the shadow property from the vector layer to make the outline of the pieces more easy to control:

http://www.darthfurby.com/genete/Other/broke.avi
http://www.darthfurby.com/genete/Other/broke.anme

-G

JCook · Post by **JCook** » Mon Mar 17, 2008 2:58 pm

Thanks for the replies.

KenW - yes, this sounds similar to what I would like to do. Ideally it would be great to be able to divide a shape with a line that you draw, as you can in Illustrator with the Divide tool in the Pathfinder pallete. If you could do this in ASPro, I think it would be very useful.

slowtiger - thanks, I'll give that a try. Sounds like it should work pretty well.

thanks,
Jack

JCook · Post by **JCook** » Mon Mar 17, 2008 3:04 pm

Genete,

I just saw your post right after I posted, and I downloaded the file and took a look. That's a very clever way to do it. I may give that a try as well. Thank you.

Jack

heyvern · Post by **heyvern** » Tue Mar 18, 2008 12:31 am

The easiest way to create perfectly aligned pieces like this is to start from a base shape and duplicate that layer.

Create the whole outer mesh for your unbroken shape. Now go in and connect the zig-zag lines to create the sections to break apart. What you should have is one big connected piece with single "break lines" cutting through it. Put in as many as needed.

Duplicate that layer and break the splines until just one piece is left.. If you have several pieces you would duplicate the original layer again and repeat.

All the break lines are absolutely perfectly aligned. there are no gaps. The tricky part now would be to adjust the points of the outer mesh where they meet at the joints if you used smooth curves breaking the splines would mess up those curves. You can even add in more points anywhere along that outer edge to achieve a smooth outline.

-vern

JCook · Post by **JCook** » Tue Mar 18, 2008 3:31 pm

Hi Vern,

What's the best way to break the spline? There's no cut tool that I know of, but I've been able to do it by putting a new point close to the place where it should be cut, and then using the Delete Edge tool to delete edges. Is that the best way?

thanks,
Jack

mkelley · Post by **mkelley** » Tue Mar 18, 2008 4:58 pm

I think you're making this more complicated than it needs to be.

I started with Vern's basic idea -- I created a basic shape, then drew interconnecting lines inside of it. I used the select points tools to select the inside shapes and the shape tool to create the inside shapes. Then I duped the layer five times (for the five shapes) and for each layer I just filled the other sections with transparency and hide the edges.

That gave me a shape on each layer that perfectly connected together with all the other shapes into one big one. It took all of about five minutes.

So -- don't bother with deleting edges, just hide them and fill with transparency and you'll have your puzzle pieces just fine (I'd post an example but I'm too lazy to upload the file to my host right now -- besides, I'm out the door to WDW. But if you don't get what I mean I'll post it later).

mkelley · Post by **mkelley** » Tue Mar 18, 2008 5:12 pm

Okay, let's see if this works (it's a PITA you can't attach files in this forum):

http://www.kelleytown.com/Shared%20Files/Puzzle.zip

synthsin75 · Post by **synthsin75** » Tue Mar 18, 2008 10:23 pm

mkelley wrote:(it's a PITA you can't attach files in this forum):

Yes sir, it defintely is. Hint, hint.

heyvern · Post by **heyvern** » Wed Mar 19, 2008 12:56 am

Good greif! Great idea Mkelly!

Of course! Don't break the points. Even easier than filling with transparency is to not fill them at all! Just delete all shapes but one on each layer. Even zero transparency slows down render times. Better to not have any fill if you just want it invisible.

I think I added the extra step of breaking the splines and making individual shapes because in my head I was thinking you might want them all on one layer. It would get hard to select the shapes if they were all the same.

p.s. For breaking splines there is a tool for that. Very handy. You press "D" to use it. You click on a line and "BANG!" it's gone. Very nice.

-vern

JCook · Post by **JCook** » Wed Mar 19, 2008 1:01 pm

mkelley –

This idea is ingenious! It works like a charm. I downloaded your file and took a look at it, and then I tried it on my own. The only difference is that after I drew the lines, and the interconnecting lines, I duplicated the layer as many times as I needed, and then on each layer I selected the appropriate points and made a shape. That way I didnt' have to make any shapes transparent. I could then animate them, and it worked perfectly.

In the animation I was working on I have already done the work of deleting edges and connecting ends of lines, etc., and it was a lot of work, but it worked. From now on I will use your method; it's much better!

thanks,
Jack