HELP WITH TRIMMING OR EVEN CONTAINMENT

sorry about the caps.

as it turns out I am having the same essential problem with two different but related components and Im wondering if I'm misisng something.

I want to in one case find all the points that lie in a region, and on the other split/trim the curves that pass through a region.

Problem in both cases is with the results: I get the insides ok but the outsides, as in the items lat land outside the containment are not right. You would think that there would be a straightforward way to use the containment test - I ended up taking the integers and just subtracting 1 to get my booleans. But whereas I get one half, inside or out, the inverse is not coming out. Strange things is that if I literally use the invert function on the dispatch the error still occurs.

any ideas why? am i using components that are buggy or is it just me?

Replies to This Discussion

Permalink Reply by Chris Tietjen on August 24, 2011 at 6:16pm

Got any images or defs you can post? It's difficult to get into your question just from the language.

Chris

Permalink Reply by Gabriel on August 25, 2011 at 7:24am

quite right. even as i was writing i wasnt sure how anyone would be able to decipher. i was pretty zapped. attached, 4 images. 2 for containment test, 2 for trim region. I am "showing" in each one the output of the stemming from the boolean bifurcation - it comes down to me thinking, perhaps wrongly, that if one result would give me the points or lines inside, the inverted boolean, or the other stream would give me those outside and vice versa. any ideas?

Point Containment - Outside (working)

Point Containment - Inside (not working)Trim Region - Outside (working)

Trim Region - Inside (not working)

Permalink Reply by Danny Boyes on August 25, 2011 at 8:10am

Output:

Coincident = 0

Inside = 1

Outside = 2

Depending on how you wish coincident to be treated, you need to make everything either 0 or 1.

Coincident to be inside: R\2 therefore 0\2 = 0, 1\2 = 0, 2\2 = 1

all 0 are inside and 1 outside.

Coincident to be outside: abs(R-1) therefore abs(0-1) = 1, abs(1-1) = 0, abs(2-1) = 1

all 0 are inside and 1 outside.

But this probably doesn't fix your problem. Why are you using the projected Points to Cull?

Permalink Reply by Gabriel on August 26, 2011 at 8:33am

thanks for that. truth is i get that. I get how to do this - the problem really though as i 've shown using different components strategies is with the booleans themselves. I've had this experience before in GH ages ago.inverted booleans don't operate as expected, dispatching values into two streams does not give you the total, but duplicates entries etc etc

beyond all that though, is there a way to use the stream gate tree component with multiple values? it would seem like you should be able to use the 0,1,2 in the state they come out of the containment test to redirect points into three separate streams; i get errors when i try, i believe the component only wants one gate trigger....

Permalink Reply by Danny Boyes on August 26, 2011 at 8:40am

Can you post your files as everything I did to test worked for me.

Permalink Reply by Wojciech Hydzik on May 9, 2012 at 8:53am

Hi guys.

I realize this was a while ago, but as it is with GH, i have a further issue with this that maybe you can help me with.

I need to subtract a list of points from multiple closed curves, not one curve as in Gabriel´s situation. The problem with this is that i get a list of multiple curves that i can´t just subtract from the point list. my method so far is subtracting one by one and then merging all the data together. the problem is that i can´t seem to feed in the merged data to subtract it from the original set of points.

any ideas?

many thanks in advance.

Wojtek.

Permalink Reply by Mateusz Zwierzycki on May 9, 2012 at 9:53am