> very similar to what I need to do. In my case, I need to work with > raster maps -- the I don't want to warp the image at all, but I want to > be able to work with the map in natural coordiantes . example: > > I load a raster map in the mercator projection. It is a big raster, and > I want it displayed as is (except for zooming and shifting). > > But I want to be able to click on it and get the coordinates of the > point in la-long, and be able to draw stuff on top of it in lat-long. > > I can provide the transform from pixel-> lat-long, and from lat-long->pixel. > > So the trick is to draw the image itself untransformed, but everything > else transformed (to match the image). > > My plan, with the old FC, was to have a "base layer" class. This class > would provide the transform(and reverse transform) from "world" > coordinates to "transformed" coordinates (and back). It would also > optionally draw something, in this case an image. I can't just drop the > image in as a regular object, because I don't want the transform applied > to it, though it does still need to be zoomed and scaled to pixel > coordinates. > > Matthias, can this be done with FC2? > >> If it is still not clear, don't worry, fc can/will do that! > > well, I'm a bit confused as to how.
If FC2 can't do that natively (what would be a pity because it seems FC2 would be a nice/useful library for that), I can write my own function to perform the transformation (camera calibration in my case) and pass these data back to FC2 to show these data, if needed. This is why I am not worried now about that. >> I hope I can help you in some way. > > yes, -- it's nice to have someone else doing something similar. > > let's see what Matthias suggests. > > -Chris > My application is much less fancy: my map is a photo of the human body in a static posture and I want to measure distance and angles of specific bony landmarks (I don't want write my own library for that, I don't have knowledge and time). The photos need to be transformed (calibrated) not only for simple scaling but also for distortion, or camera view, or 3D reconstruction (once again, I can (and for some I will have to) do these transformations in python/numpy). For my application, and probably for you i guess, a high-level FC2 class with a gui mode for measuring distance and angle would be very welcome (and do that considering different systems of coordinates...). I will try to do something simple for that, but I am a newby in python; don't expect to use my program :( Marcos Duarte http://lob.iv.fapesp.br/ University of Sao Paulo, Brazil _______________________________________________ FloatCanvas mailing list [email protected] http://mail.mithis.com/cgi-bin/mailman/listinfo/floatcanvas
