How to 'crop' a g-code

[paulus.v]

Which leaves you with a set of moves which don't join up and aren't linked ;-)

Doesn't matter. The moves are the dotted lines in my sketch. There will be a G1 move from the last point of one texture line to the first point of the next line. It will cut through air anyway.

[magicniner]

Doesn't matter. The moves are the dotted lines in my sketch. There will be a G1 move from the last point of one texture line to the first point of the next line. It will cut through air anyway.

Sorry, I didn't realise it was so simple, I await your elegant software solution with bated breath, meanwhile the rest of the world does this in CAD/CAM

[Greeny]

In geometry, the term for what you want to do is 'clipping'
Try a search for 'polygon clipping'
It seems like a simple task but is made difficult by lots of tricky edge cases.
If you can code in c++ or c# or Delphi i can recommend Angus Johnsons excellent freeware 'Clipper' http://www.angusj.com/delphi/clipper.php
Cheers

[magicniner]

If you can code in c++ or c# or Delphi i can recommend Angus Johnsons excellent freeware 'Clipper' http://www.angusj.com/delphi/clipper.php
Cheers

That looks like a really useful bit of software written by someone with an understanding of the problems involved in truncating lines with a shape, but surely the problem with G Code is "Simple" ? :D

- Nick

[paulus.v]

A late response on this problem...

In geometry, the term for what you want to do is 'clipping'
Try a search for 'polygon clipping'
It seems like a simple task but is made difficult by lots of tricky edge cases.
If you can code in c++ or c# or Delphi i can recommend Angus Johnsons excellent freeware 'Clipper' http://www.angusj.com/delphi/clipper.php
Cheers

First of all thanks a lot Greeny for pointing me in the right direction!

For a programmer it was a 5 minutes job. The solution was simpler than the clipper library (certainly included in the library as well), it is called ray casting algorithm.
Here are code examples.

I don't think you realise just how complex a mathematical problem what you're asking for constitutes

Nick, I'm sorry to tell you that this complex mathematical problem is done by a computer in less than a second, by comparing 50k points against a 12 points defined polygon.

[magicniner]

Nick, I'm sorry to tell you that this complex mathematical problem is done by a computer in less than a second, by comparing 50k points against a 12 points defined polygon.

Paulus,
I'm sorry to have to tell you that how quickly a computer runs a chink of code has no relationship to the complexity of the maths used by the programmer to address the problem or how smart the programmer had to be to write the code :D

Or could any dummy have done the job? ;-)