Multiple build plates, empty-layer bug and outdated 2D packing

I’ve recently started using Formware and, so far, I’m getting good printable results from it. There are two features I’m missing, though, plus one related bug.

Multiple build plates

I would really like to be able to create and switch between multiple build plates inside one project, as is possible in most current consumer slicers.

This is especially useful when preparing all the parts for a product that cannot be printed in one go. Keeping the parts on separate plates inside the same project is much more convenient than leaving the remaining parts outside the print area, and it makes it much easier to keep track of what belongs to each print.

Objects outside the print area create empty layers

Leaving parts outside the print area also exposes what appears to be a slicing bug.

If an object outside the printable area is taller than the objects on the plate, Formware creates empty layers up to the height of that object. An object that is completely outside the printable XY area should not affect the sliced file. It should either be ignored or trigger a warning.

Multiple-plate support would remove much of the need for this workaround, but the slicing behaviour should still be corrected.

Automatic 2D arrangement

The automatic 2D arrangement also seems quite outdated compared with Chitubox.

I tested both using the same parts and printable area. Chitubox fitted seven parts in around three seconds. In Formware, opening the 2D nesting tab alone took around ten seconds. Using “Top left”, 0.1 mm spacing in both directions and the maximum of 50 rotations, the actual arrangement then took another 14 seconds and fitted only six parts.

So Formware took substantially longer while still fitting one fewer part. It also tends to leave gaps that seem large enough to use.

This is a well-studied problem, and projects such as `jagua-rs` demonstrate how quickly large numbers of placement candidates can be evaluated using modern 2D nesting techniques. I would mainly like to see Formware’s packing algorithm modernised so that it can search more possible arrangements and produce denser results in less time.

Increasing or removing the limit of 50 rotations would also help, possibly together with a choice between a quick arrangement and a longer search for the best result.

The actual sliced results from Formware have been good for me so far. Improving these older workflow areas would make it much nicer to use for complete production projects.

Hi,

Thanks for the input.

Multi buildplates: you are the first to ask; but I see your use case. Makes sense.
I'll add it to our todo list.

Slicing bug: I'm not aware of this bug i'll check it.
It should discard any objects not overlapping the build platform. There is also a setting how to handle slice contours of parts that partially go outside the platform.

Nesting: i'm curious what parts you are trying then. I also don't get why it takes you 10 seconds to start up the command; it should be insant.

You can choose which algoritm you prefer; if you want more speed use the convex only shapes. If you want irregular (true shape) nesting it takes some more time.
Both algoritms are custom written and are 100% numerically robust. So they don't suffer in any way from floating point errors; which is a major problem in these problems.

Il'l read the paper from jagua-RS; can be very interesting.

kind regards
Elco

just as an example for Jagua - I use it for our product manuals (bottom right is reserved for a QR code in the final output - basically the outline is projected onto a 2d plane, then simplified then jagua arranges it, transformations get applied to blender and rendered.

For the 2 youtube videos - somehow nvidia recorded them with periodic flashing rainbows - sorry for that, that is something I do not see when using the software. They are still clear enough though only happens every now and then.

youtube.com/watch?v=r_Y-qNAVdVQ&feature=youtu.be

I've uploaded a video of what I mean with it misbehaving a bit above - seeing the user do it once is probably more useful than me trying to explain it again :P

This time the menu opened quickly, but the second run took forever. Of course, I don't care about time - it can take 15 minutes for all I care, as long as it can fit 7 parts on the plate like Chitu does - from ca 1:27 onwards you can see Chitu run the auto packing on the same parts and fit 7 for the same print dimensions.

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https://www.youtube.com/watch?v=cIUh1pmSd90&feature=youtu.be

This is the bug I am experiencing with slicing (empty layers). So I have found that when I move the other parts further away from the plate this does not happen. this is however, how the auto placing has placed the parts. The slicer based on the object count to be sliced treats them as on plate. I guess if multiple plates are added and the auto arrange spreads the parts out over as many of the plates as it needs this would be resolved as they wont be that close to the plate. (chitu just adds more plates if the parts dont fit)

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The auto packing, as dumb as that sounds, is right now the main thing that would prevent me from using this slicer as my main workhorse - we print a lot of different models so storing arranged plates for them is not feasible and manually arranging would lose me a lot of time.
The slicing and reliability of that has been amazing so far - the software even throws a warning on the empty layers which is great so I can skip UV Tools. The depth of adjustments possible via the settings is also amazing.