Hi, with Christian we've discussed this topic almost to death, let me summarize and ask for final feedback on the topic.
What I propose is to add two new FeatureSource Hint, - Hints.GENERALIZATION_DISTANCE, expressed a a double, intended to be a hint of the minimum distance between two subsequent points in the generalized output, or to say it another way, an indication of how much the geometry shape can be altered as a result of the generalization (anybody cares to word this better?) - Hints.PRESERVE_TOPOLOGY, a boolean, intended to specify whether we can accept topologically invalid geometries as a result of the generalization As usual the feature source will indicate the support for the two hints by advertising them into ... The two use cases for these hints are for rendering and for WFS output. We assume a generalizing feature source can get some significant speed benefits by doing in datastore generalization, for example: - a spatial database with a fast on the fly generalization routine that results in less data transfer from the database to the gt2 code - a datastore that has pre-generalized data sets (vector data pyramid) and thus, can cherry pick the proper version to pick and use The topology preservation is usually not required for rendering, and can open the door to quicker on the fly generalization routines, whilst we definitely want topology preserved geometries if we're serving them out in WFS. We want to introduce these two new hints in gt2 2.5.x and trunk. Opinions, feedback? Cheers Andrea -- Andrea Aime OpenGeo - http://opengeo.org Expert service straight from the developers. ------------------------------------------------------------------------------ _______________________________________________ Geotools-devel mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/geotools-devel
