(Transform by) Landmark Correspondences
The plugin Landmark Correspondences calculates a transformation between two corresponding landmark clouds and renders a transformed image. The landmarks are read from point selections over two images. The transformation is estimated by a least squares or Moving Least Squares fit for the available models.
The non-linear non-invertible transformations as estimated using the Moving Least Squares method are rendered through a mesh of triangles whose resolution is a parameter of the plugin, see Interactive Moving Least Squares for an intuitive explanation.