Calibrate the M values of a line layer with chainage (PK) values from a point eventslayer. Each point is projected onto the nearest line and used as a calibration control to interpolate and assign the M value along the axis.

INPUTS

• Line layer (with or without existing M). • Reference point layer (events). • Chainage (PK) field in the point layer (PK). • Chainage (PK) units: m, km, or Auto. • M output units: m or km.

POINT–LINE MATCHING

• Points are projected onto the nearest line within the maximum distance. • Group by ROUTE_ID (optional): forces PK events to calibrate only their corresponding road/route. (Requires specifying the ROUTE_ID field in both points and lines).

CALIBRATION

• Projected events (PK) act as control points, and M is assigned by interpolation between control points. • Behavior outside control range: choose the mode (Extrapolate / Clip / Flat / NULL). • Factor and Offset (advanced) are applied to the final M (in output units).

ADVANCED OPTIONS

• Generate projected points: auxiliary layer for review and quality control. • Generate issues table: only if warnings or errors exist.

OUTPUTS

• Calibrated lines with LineStringM/MultiLineStringM geometry. • Projected points (optional). • Issues (table, optional).

WARNINGS / ERRORS

Reported in the Processing log and, if enabled, in the issues table.

DETAILS

See the plugin README: Calibrate lines from points/events