Milton Jonathan ha scritto: > Hello again > > Oh, I was just thinking about it theoretically, and trying to spare a > separate rescaling phase. > > Probably it's not practical, but my view is that if people are not using > units like meters or feet but still want the symbolizers to remain the > same size on paper (or on screen), regardless of resolution, then all > sizes should be given in millimeters, inches, etc (that is, explicitly > specifying what the user really wants). Giving it in pixels is simpler > but in this case it seems like saying "I want the symbolizer to show on > paper the size it would show on screen using 20 pixels and 72 DPI, so > please fix that size because I am now using 300 DPI". Shouldn't he just > say that the size is 20/72 inches?
Correct except that we don't have support for screen units other than pixels. The renderer ultimately works in pixels, and to get a metric screen unit to work we'd have to pass down the DPI anyways. I have to admit that I don't know what exactly will happen when we have to support metric screen units with a double rescale approach... but it should work, a first rescale to get the number of pixels to represent something at the stadand DPI, and another one to reach the target DPI. Looks to me like it should work, but maybe not :-p > On the other hand, rescaling the map with a user given value looks like > a valid functionality anyways - it gives flexibility, and who knows what > the user may want to do? :). What do you think about a simple rescaling > parameter? In this case, he could state something like > scalefactor=300/72 (instead of saying that the original DPI is 72 but he > now wants 300). Does it make sense to you? It makes sense to me but will confuse everybody else since all of the other WMS servers seem to have the user specify the target dpi. If people feel strongly about this I can have the WMS param be a dpi, and then pass to the renderer: - a target dpi to compute the proper scale (that is there already) - a separate param to rescale symbolizers But that does not look too good honestly Cheers Andrea -- Andrea Aime OpenGeo - http://opengeo.org Expert service straight from the developers. ------------------------------------------------------------------------------ ThinkGeek and WIRED's GeekDad team up for the Ultimate GeekDad Father's Day Giveaway. ONE MASSIVE PRIZE to the lucky parental unit. See the prize list and enter to win: http://p.sf.net/sfu/thinkgeek-promo _______________________________________________ Geotools-devel mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/geotools-devel
