On Mon, 22 Mar 2004 20:37:52 +0200, Athanasios Mantes <[EMAIL PROTECTED]> wrote in message <[EMAIL PROTECTED]>:
> Hi all, > > I'm an OpenGL developer, currently developing a small terrain model > renderer. I'm sending this message to this list, because I think that > developers of FlightGera hav come up with similar subjects and can > provide me with a working solution. > > What I want to achieve is to render multiple terrain grids of > different resolution that contain common areas without the rendered > models to "mix" because of the different resolutions used. That is > similar to "cutting rectangular holes" to terrain models, without of > course preprocessing, splitting, or braking the initial terrain grids > into pieces. Let's say I have three rectangular heightfield grids, the > one covering the entire North Anerica terrain, with a resolution of 1 > km, a grid covering the USA area with a resolution of 500m and a grid > covering the area of Nevada state with a resolution of 100m. I want to > be able to render those grids together at the same scene, but because > of the different resolutions, the heightfields mix in many cases. > > So the ideal thing (and what I want to achive), is that when rendering > those grids, I want to be able somehow to punch a vertical rectangular > hole in the correct position and with the size of the USA grid in the > North America grid, place the USA grid there, and then put a verical > hole in the Nevada area in the USA grid, and place the Nevada grid. > Grids are not "aligned", so that can't be done by preprocessing grids > and cutting the right holes in them. > > So I am asking for a way, or technique so as when rendering an object > after another, to avoid rendering the part of the object that is > vertically (same x,z coords) "covered" by the previous object, so as > to avoid mixing them. Here > (http://students.ceid.upatras.gr/~mantesat/render.jpg) is a quick note > about the clipping I want to achieve. It is a side view of a rendering > of a terrain model, consisting of three datasets. ..how about 2 "data mix zones" 'between' your own 3 data sets? If the offsets are as wild as in your jpg schetch, you may want to weigh the data over the data mix zone width, and make the zone say a mile wide, so it looks reasonable. > How does FlightGear face similar problems? ..discussed by the guys in the thread. -- ..med vennlig hilsen = with Kind Regards from Arnt... ;-) ...with a number of polar bear hunters in his ancestry... Scenarios always come in sets of three: best case, worst case, and just in case. _______________________________________________ Flightgear-devel mailing list [EMAIL PROTECTED] http://mail.flightgear.org/mailman/listinfo/flightgear-devel
