purge extruders with origin center is off printing area for dual extruders

[photodude]

Version

Build: PrusaSlicer-2.1.1+win64-201912101512
and
Build: PrusaSlicer-2.2.0-rc2+win64-202003071138

Operating system type + version

Operating System: Windows
System Architecture: 64 bit
Windows Version: Windows 10 (build 18363), 64-bit edition
Total RAM size [MB]: 34,307MB
OpenGL installation
GL version: 4.6.0 NVIDIA 441.87
Vendor: NVIDIA Corporation
Renderer: GeForce GTX 1070/PCIe/SSE2
GLSL version: 4.60 NVIDIA

3D printer brand / version + firmware version (if known)

BIBO2 Stock model with 5015 part cooling blower and PEI sheet build surface
BIBO MFG provided stock firmware based on the Marlin 1.0.0 shaqFoo Ditto printing fork

Behavior

When the origin is in the center of the bed the purge all extruders results in the purge line being at 0 Y and 50% X length. unfortunately this results in the tool path being outside the print area.

• Steps needed to reproduce the problem

1. multi extruder print (in my case a 2 color print for dual extrusion)
2. set origin at center of the bed
3. turn on wipe tower and purge all printing extruders
4. slice
5. tool path outside the printable area.

• Expected Results
  Purge line should be at the front of the bed and inside the printable area.
• Actual Results
  the current behavior is the purge line is at 0Y and 50% bed length for X resulting in the purge line in the middle right of the bed with 50% of the purge line outside the printable area.

Is this a new feature request?
A re-positionable purge line, like the wipe tower can be repositioned, would be helpful.

printer configuration can be found in my Github Repo or the open PR #3804
https://github.com/photodude/BIBO2-PrusaSlicer

Project file

bulbasaur_dual_detail.zip

[lukasmatena]

You are right, this was in there for quite a long time (probably always). The priming lines were printed with respect to coordinate system origin, not to "bottom-left" corner of the bed.

I hope I fixed it with a48a796. The fix will be in 2.3 release - 2.2 is now too close.

Closing the issue.

[photodude]

@lukasmatena Awesome, thank you for fixing that. Sorry, I wasn't able to fully write up the Issue I originally mentioned in this comment until now. Too bad it won't be in 2.2.0 but at least it will be fixed in the future.

[lukasmatena]

After giving it a bit more thought, we decided to squeeze the change into 2.2.0. It is now in master as a6a7736. Hopefully it won't break anything.

[photodude]

@lukasmatena Awesome I'll see about giving 2.2.0-rc3 a try once I do some maintenance on my printer. (time to replace some fans)