Am Donnerstag, 28. August 2003 21:34 schrieb Jim Wilson: > My apologies, I can't answer this. Somehow it doesn't appear that the > Flying Fortress screenshots look any more natural than ours. The shots > seem to have a sort of "oil painting" look to them.
It is the shape of the textures that look more natural. In flighgear you have allways squares, in FF2 you have random shapes build of very small textures. I have the full version of FF2 and took a closer look on the ground detail of the game today. My conclusion is the following: They use very small squares of textures (about 4m * 4m large) and create one big one (100m*50m) of them but with a random shape. For example they have a 4m*4m cornfield texture, then they glue 20-30 of them togehter and create a large cornfeld. The large cornfeld now has a random shape it is not a square with 90 degree angles like in flightgear. After that they create another big field, also made of small textures but with another color or terrain (darker corn field, forrest, plaines or something else). Then they glue the two large cornfelds together. But on the place where the large cornfelds are glued together the edge they use a third terrain texture like a hedge/covey and put it on top of the edge. This third texture could also be a street or country road. I try to descibe it with ASCII charactes: Let's assume our first corn field texture is "X" (where "X" is the small 4m*4m texture) and our second one ( a wheat texture) is "O" then it looks something like this: XXXXXXOOO XXXXXOOOO XXXXOOOOOO XXXOOOOOOO XXOOOOOOOOO XOOOOOOOOOO Now they put on top of the edges a third texture like a street "H" with loos trees "W" (the 4. texture) ": XXXXXXHOOO XXXXXHOOOO XXXXHWOOOOOO XXXHOOOOOOO XXWHOOOOOOOOO XWHOOOOOOOOOO After that the terrain looks natural because it's hard to find the hard syntethic looking edges between different kindes of textures which are typical for computer games. In flightgeare we have one large texture for a typical terrain type and it is in most cases especially on flat land a square with 90 degree angles: ---------------------IIIIIIIIIIIIIIIIIIII ---------------------IIIIIIIIIIIIIIIIIIII ---------------------IIIIIIIIIIIIIIIIIIII ---------------------IIIIIIIIIIIIIIIIIIII ---------------------IIIIIIIIIIIIIIIIIIII The large texture may be for itself look ok or photorealisitc, but that doesn't look natural when you glue them together. And it looks even worse when the shape is a square with 90 degree angles that looks blocky. For creating the large corn fields in FF2 they make a lot of use of Mip Mapping for that to keep the framerate high. But i don't know on what principals they create those different shapes and different sizes of the large cornfields (and other fields). I agree with the "oil painting", i don't know what's responsible for that (maybe they use bump mapping for that) but it is not the thing i wanted to show (explain) or have in flightgear. I only meant the randomly shaped landscape. > > Not to say that we couldn't improve ground detail! Can you tell us more > about what we are looking at? Is shot #2 just a texture (with static > shadows) or is it 3D models/scene with shadows that move with the time of > day. How much total area is covered with that level of detail? You can see the shadows of the hedges or trees only when you fly very close over the ground. I assume they put a grey alpha texture next to the small hedge or tree textures just in time when you fly close over them to get this effect. So it is probably created only once in the moment when you get closer to the ground and so it is probably a kind of semi-static shadow. Keep in mind that you are flying, so I don't think they recalulate their position based on the sun position in every frame. But maybe they change the postition every 30 minutes, that shouldn't stand out. > > The sky is fairly unremarkable compared to ours. > But the ground lighting > is really neat. I wonder if we could somehow come up with a scheme to > mirror a grey alpha shadow version of the cloud textures just above the > ground polys to get something similar. I like that idea, maybe it is worth to try that. Best Regards, Oliver C. _______________________________________________ Flightgear-devel mailing list [EMAIL PROTECTED] http://mail.flightgear.org/mailman/listinfo/flightgear-devel
