Refer to this MR: Draft: Add Blurring mode to Smudge Engine (!1460) · Merge requests · Graphics / Krita · GitLab (kde.org)
It is worth mentioning that the mode of CSP is the same as the blurring of paintstorm. They do not blur all dab, but only the first dab.
The remaining behavior is consistent with Krita’s smearing. Therefore, by making some modifications to ‘smearing’, a similar effect to CSP can be achieved.
