Testers required for "exact" z-seam positioning in Cura development builds

[burtoogle 426]

Hi,

 

I have been working on implementing "exact" z-seams to avoid the rather ragged seams that can occur on curved surfaces.

 

Here's an example: first is how it was before and second is what the experimental code now produces (I have enabled coasting just so that it makes the z-seam location more obvious...

 

 

 

This new implementation is only active when the Z Seam Alignment setting is "User Specified" and the Seam Corner Preference is "None".

 

Before, when those settings were in use, for each layer, it would choose the wall vertex that was closest to the z seam X/Y position to be the location of the z-seam. Unfortunately, the vertices are not guaranteed to align vertically unless the wall has a sharp corner (i.e. with a rectangular shaped wall, you would expect the vertices at the corners for the adjacent layers to be stacked on top of each other) so the seam comes out horribly ragged. Using a finer model mesh and small resolution values help but what it really needs to do is get away from the constraint that the z-seam has to pass through the vertices of the walls.

 

What it now does is take a vertical slice through the model using a plane that passes through the z seam X/Y position and the centre of the model's bounding box and finds where that plane cuts the model's walls and uses that as the z-seam location. Generally, the plane will cut through the model at least twice (goes in one side, comes out the other) and so it chooses the side closest to the z seam X/Y position.

 

If the plane doesn't pass through the model at all, then it just falls back to the previous behaviour of choosing the wall vertex nearest the z seam X/Y position.

 

Makes sense? Well, even if not, I would be grateful if those of you who are using my experimental builds could give this a try some time and let me have some feedback as to whether this is a good scheme or not.

 

Please note that due to a recent change in the build process, if you are using Windows, you must remove any previous installations of my build before installing the current builds. Otherwise, it will not run.

 

As always, my builds can be found at: https://www.dropbox.com/sh/s43vqzmi4d2bqe2/AAADdYdSu9iwcKa0Knqgurm4a?dl=0

 

All feedback is welcome.

 

[Smithy 554]

Fantastic idea and great feature! It was always annoying that the seam was not really straight in some models.

Will give it a try the next days.....

[burtoogle 426]

Thanks, I will need to make a MacOS build for you, will do that later today.

[Smithy 554]

Don't stress please.....

Thanks! 🙂 

[mtnbkrrick 0]

Is there a way to "paint or draw" a line where the z seam would go? The line could be free hand or orthogonal.  This sounds difficult but figured I would ask.  Nice work!

[burtoogle 426]

1 hour ago, mtnbkrrick said:

Is there a way to "paint or draw" a line where the z seam would go? The line could be free hand or orthogonal.  This sounds difficult but figured I would ask.  Nice work!

 

No there isn't any way to do what you ask and it would be a big job to implement that I should think. It would involve UI programming to do the drawing and then the z-seam contour would have to be passed to the slicer back end which would then work in a similar way to what I have implemented in this recent development.

 

Personally, I would not find it a useful feature because I can't draw a nice line using a mouse so the z-seam would end up at least as wobbly as it is now.

[Dim3nsioneer 504]

While I may have similar issues drawing a straight line with the mouse 😉 it might be a very interesting feature to be able to drag the z seam along the surface of an object starting from a certain xy coordinate on the ground plane. That line might then go up the object in different ways (along x, along y, radially from the center of the build plate, radially from the center of mass, radially from a custom xy coordinate, etc.).

[alexjx 8]

This is really cool feature! I would like to use this. Thank you for bring another great feature.

 

Have you pushed to your github? :)

Edited October 25, 2019 by alexjx

[burtoogle 426]

5 hours ago, alexjx said:

Have you pushed to your github? 🙂

 

Yes, my mb-master branch in CuraEngine contains this feature.