Distorted structure representation when opening saved macromolecules in micro mode in CML, CDX, CDXML, Base 64 CDX formats
- Dominant language
- C++
- Stars
- 406
- Forks
- 134
- Avg merge
- 2d 11h
- Merged PRs (30d)
- 24
Description
**Steps to Reproduce**
1. Open file in Macro mode (Flex mode) [monomers-cycled.zip](https://github.com/user-attachments/files/17281569/monomers-cycled.zip)
2. Switch to Micro mode

3. Save as CML, CDX, CDXML, Base 64 CDX
4. Open saved files
**Actual behavior**
Upon reopening the CML, CDX, CDXML, Base 64 CDX0 files, the structure appears distorted, with bonds incorrectly placed, resulting in a non-cyclic structure (as shown in the screenshot). The original intended shape and arrangement of monomers are lost.

Screen from CDX also not fine:

**Expected behavior**
The saved structure should maintain its original form upon reopening, appearing as a cyclic structure similar to the screenshot.

**Desktop:**
- OS: Windows 11
- Browser Chrome
- Version 128.0.6613.120 (Official Build) (64-bit)
**Ketcher version**
[Version 2.26.0-rc.1]
**Indigo version**
[Version 1.25.0-rc.1]
Bug found during testing: https://github.com/epam/ketcher/issues/5400
Contributor guide
No contributing guide indexed for this repository
Research direction
Start by reproducing the report with monomers-cycled.zip in Indigo/Ketcher using Micro mode, then save and reopen each listed CML, CDX, CDXML, and Base64 CDX format. Compare the reopened structure with the original cyclic arrangement; done means bonds and monomer geometry remain correct in every format.
Written by the indexing model from the issue text.
Assessment
- Tech stack
- cpp
- Domain
- backend
- Issue type
- Bug
- Difficulty
- 4/5
- Estimated time
- 3-5 days
- Activity status
- Stale
- Clarity
- Mostly clear
- Newbie friendliness
- 35/100