Richard Weait wrote: > On Wed, Sep 26, 2012 at 12:59 PM, Olivier Croquette <[email protected]> > wrote: > >> If no, it doesn't make any sense to me that a vector based process for the >> cadaster is an import, and a raster based is not. Everything is the same : >> kind of data, license, provider… >> >> There seems to be a contradiction there. > > Yes, this is something of a contradiction or edge case. May I offer, > from my perspective, an important difference between tracing over > raster, and copy / pasting vectors? You say: > > "Some cities (10% as an order of magnitude) have only a raster > cadaster, in which case the mapper has to draw all the nodes and > points manually." > > I think that "drawing all of the nodes and points manually" is an > important difference, from a quality point of view. Each node or way > that you draw by hand, is carefully considered and placed, one at a > time. It isn't perfect; nothing is. I suggest that this leads to a > kind of automatic quality control, as the nodes and ways are placed. > > The goal of the vector import procedure is similar, use data from this > area, reconcile it carefully, include it in OpenStreetMap. The > intention is very good. But in execution, it is easier to miss a node > or way (or more than one) that needs to be refined before upload. > Again, it isn't perfect; nothing is. When you are considering > hundreds or thousands of nodes and ways at once, it becomes time > consuming to check them all. > > I hope that you'll find the above to be easy to agree with. > > My conclusion, is this. The quality of the hand drawn nodes and ways > will be better because when we draw the nodes and ways by hand they > get more individual attention and care than when we start with a group > of nodes and ways from another file. > > So that's why I think that it is different to trace by hand, vs. > vector import.
I've read those paragraphs several times, but still don't really get your logic. Are you claiming that from two options 1) check+manually trace the data, 2) check vector data, the first one leads to a higher quality output? My perspective is that man-hours are expensive commodity and we should treat it that way and put it to a good use. And I don't think that hand-tracing vector data falls into that category. Best regards, Petr Morávek aka Xificurk _______________________________________________ talk mailing list [email protected] http://lists.openstreetmap.org/listinfo/talk
