A QGis plugin to transform a vector file of points into polygons (squares, rectangles or polygons) centered on those points. Optionally, the centroid of an input layer can also be created (the centroids of the features found in the input layer are generated and saved in a shapefile).
The polygons dimension is defined by the padding parameters (for a square, the width is two times the padding value). If the input file is a vector file of lines or polygons, the centroid of the features will be used to center the polygons. The output polygons can be rotated, by changing the rotation angle, 0 means no rotation is applied.
A test data set (a shapefile of points, in EPSG:4326) is provided under sample_data in the plugin directory. Open this file in input, choose a filename for the ouput, then select an output shape (such as square or rectangle or hexagon), then a size (for example, 0.1, as the dimension is in degree for EPSG:4326), then click "OK". If you let the option "Open in QGis" checked, the result will open in QGis.
More details: https://github.com/BrunoCombal/PointToPolygon/wiki/Manual