Jigsaw block generation is offset by a block and ignores direction

I see nothing wrong on these images. The jigsaws are supposed to connect to each other across the structure template edge, and it appears that they've done so.

What exactly are you expecting?

You’re right. The images seem to be showing what should happen instead of what does. When actually using them to generate a piece of a structure in game the first one generated often  generates with its connecting jigsaw block one block lower than the starting jigsaw. Additionally, orientation seems like it can be ignored for the first manually generated piece. The jigsaw blocks don’t necessarily align orientation wise and can be at 90° or even 180° relative to the starting piece (unlike upon world gen or /place structure where they align). I don’t have any pictures at the moment, but I’ll try to get some soon.

@slicedlime

I'm back! Ok, so those images are showing what's wrong, but it isn't clear. They manually activated a jigsaw which placed one cube one block lower and then another branched off it back into the first (you can see the higher ring of sea lanterns). The second image is in an odd T shape from where it rotated itself 90 degrees for some reason. Regardless, I've made a datapack and have plenty of images to try to clear things up. First up, my cube template:

When using /place structure I get (which in my pack is a size of 2 so not sure why it's so long. Different bug or me just not knowing how this works?):

Anyway, I /place a template and manually activated a jigsaw with a size of 1 (so again, not sure why it's so large):

The one that looks like it's being intersected was the starting one. I would've expected them to continue out in a line, not cut back into itself at 90 degrees. Here you can see that the jigsaw blocks would've been in line, but one block off on the Y axis and facing the wrong way (circle is where original, starting jigsaw I manually activated would've been had it not been overwritten and I rebuilt some of the frame out of different blocks for visibility):

The pack for those interested:

However, you don't need the pack. You can see it with villages too!

Below is minecraft:village/plains/streets/corner_01:

After generating a house off the one house jigsaw you can see the jigsaws align but are off 1 on the Y axis and the door should point towards the road (for clarity, this image is at a different angle than the above it's the outside of the corner instead of inside):

Thank you for that additional info. "size" is actually "max depth", so what you're seeing is consistent there - size=2 means 2 jigsaw connections traversed out from the start.

Village templates do have some old oddities (including the "use expansion hack" flag on the jigsaw), so those might generate a bit messy if you generate them without using the structure. However, that doesn't explain the test pack behavior, which does seem wrong.

Can confirm in 1.19.3 and 23w06a.

Can also confirm in 1.19.3 and 1.19.4 pre-release 3.

I recently started to create a datapack that adds a new subterranean procedural dungeon (I know, very original) but when I test it, the jigsaw blocks just don't work at all. I changed the jigsaws, the template pools and created a new world to test but the jigsaw keeps generating incorrectly. i am adding some screenshots along with the datapack and a world i used to test

I feel like I should add for people struggling with this issue that this only affects manually placed jigsaws. Generated structures with jigsaws are not affected.

Confirmed in 1.20 pre-release 2.