Trim Function

Kendall-DM

Can someone give me a quick rundown of how the Trim function works? I've been using it, but without much success. I've looked through the manual, but it isn't helping. Does it only work with lines, or can it work with entities too? Essentially, I have a river that runs through a land contour, and I want to trim the river so that it meets up with the land contour but doesn't extend beyond it. Since the river is a line and the land contour is an entity, I though Trim to Entity would work. In fact, I've tried all the trims, and the only thing I can accomplish is the trim the river in relation to itself (and thus, just deleting a large portion of it). Just can't seem to figure out how to make the Trim function work! Help?

anomiecoalition

Can't really explain "trim" well to you (for that kind of specifics you would probably need the tome...which I don't have)...but I think there might be a workaround to fix your particular problem. If you want your river to meet another line/entity after the fact - your easiest solution is to simply trim that river/line (i.e. deleting a portion of it), then select the appropriate line drawing tool, click the "end point" button, click on the end of your river/line, click on the "on" button, then click the point on your contour that you want the river to extend to.

I've learned the hard way that the "end point" and "on" buttons are my best friends with CC3. But...if anyone knows an easier way to fix this kind of issue - please let us both know.

Kendall-DM

I did my own "rather painful" workaround. I went to each river meeting each contour and sculpted the contour there to meet the river with an extreme zoom. Two hours of work, but it's there.

But yeah, in playing around with Trim, I have no clue what its functionality is for.

Shessar

You should be able to trim a river to a contour using trim to entity. Make sure the entities are not on frozen layers.
After clicking the trim to entities button, first select the entity you want to trim to, then select what you want to trim. Where you click on the object to be trimmed will determine what part of it will be trimmed.

sdavies2720

I haven't trimmed smooth entities in a while, but I recall that they are a little finnicky. I'd suggest:
* Make a copy of the map to play with
* Try turning off smoothing on the river
* Try trim
* Turn smoothing back on

You may have issues with the shape of the river changing when trimmed unsmooth.

Steve

Kendall-DM

Posted By: ShessarYou should be able to trim a river to a contour using trim to entity. Make sure the entities are not on frozen layers.
After clicking the trim to entities button, first select the entity you want to trim to, then select what you want to trim.Whereyou click on the object to be trimmed will determine what part of it will be trimmed.

Ok, that worked, no intuitive to click the part I wanted to keep, I never tried that. Unfortunately, it just squares of the end of my river (it doesn't trim flush to the entity), so my workaround is actually a better solution at this stage. Thanks for the reply guys!

leosuth

You could explode the entity you want to trim to - zoom in and trim to the appropriate resultant straight line.

If I am in a hurry and don't particulary want to faff around, or the entity cannot be sensible exploded, I just draw a line over where I want the trim to occur, trim to that line, then delete the line

Sorpaw

Another issue - are there any things that TRIM will not work with (circles, caves, etc..)?

JimP

never mind

Sorpaw

Again, are there any things that TRIM functions will not work on?

Sorpaw

Joachim de Ravenbel

Well, the Trim To Entity and Trim to Intersection sometimes works odd with arcs and fractals.
I often have to make entities cross before triming to fractals.
With arcs, it seems to keep the greater part of the arc regardless of where you selected the arc. In this case I usually split the arc near the intersection point, delete the unwanted part and then trim to entity/intersection.

Ralf

Sorpaw, you can't TRIM a closed entity (e.g. a polygon, a circle) to something else, but you can trim open entities (paths, lines, arcs) to those. As Joachim says, getting Trim to work correctly can sometimes be fiddly. Extending entities to actually cross the object they are to be trimmed to, and breaking them into smaller parts are good ways to get the Trim to work as required.

Sorpaw

OK, Ralf, I think that I understand. Closed entities are a no-no. Can caves be joined without a passageway? Are they considered entities?

Sorpaw

Ralf

Everything in CC3 is an entity. Text, paths. lines, polygon, curves, arcs. etc. A "cave" is just a polygon (smooth, straight, or fractalized) that has been drawn with the cave drawing tool.

And yes two polygons can be joined. The way to go about it is usually:

- "Break" both poylgons, removing the overlapping parts that will not be a part of the outline of the resulting, merged polygon. You now have two "paths" (a polygon is just a closed path).
- Use "Combine Paths" to merge the two paths into one.
- Use "Path to Poly" to close the new path and make it into a polygon.