Indicatrix mapper
The plugin generates Quasi-Tissot Indicatrices as dynamic ellipses to visualize map projection distortions. Using numerical derivatives (Quasi Indicatrix method), it calculates precise scale factors and rotation angles for any project CRS. These point-based indicatrices provide an analytically exact representation of local distortion, updating in real-time as the project projection changes.
The extent and resolution of the indicatrices and the graticule are fully customizable. The radius parameter controls the visual scale of the indicatrices, which can be defined in kilometers or degrees. This method provides high precision even for complex projections where symbolic derivatives are unavailable. Analytical distortion parameters (h, k, s, ω) and the principal axes (a, b) with their orientation (angle) are derived using the Quasi Indicatrix method (Bildirici, 2015). QGIS contains approximately 2700 categorized projections; you can test the distortion effects on your region or the entire globe instantly.