Hi Thorsten, Thank you, too!
> This becomes a performance issue eventually - see Paris (France). Random > buildings scale well for memory and performance because they're numerous > instances of the same building, so just the various positions need to be > stored separately - a city full of unique buildings needs to store each > building uniquely. The basic idea doesn't really scale well. It looks impressive, and scales well enough on my machine, which isn't really high end: i5-2500k, GT640TI. The basic idea would be: Based on landclass data and OSM roads, generate a unique hi-res texture for a few km out. (maybe using a base texture and overlays as you desribe below.) Gradually reduce texture resolution for terrain further out. (I did some rough estimate which indeed showed I need plenty of video RAM, but not several GBs.) Regenerate the textures as the camera moves. I have no idea if current CPUs/GPUs are fast enough for such a scheme. Or if there's a better way to achive this. This is why I'm asking you guys. > This isn't as impressive as you think - the kind of graphics card that can > deal with 11.000 unique terrain texture sheets in the scene (you need > something of that magnitude, see the numbers worked out here > http://wiki.flightgear.org/Procedural_Texturing#Photo_texturing ) is also > the kind of graphics card which can go through millions of vertices. Terrain that is 100km out doesn't need 1m/px resolution. I'm certainly thinking of a LOD scheme here, so I won't need 11.000 unique texture sheets. > > + shared models with an individual piece of ground texture > > Well, but how does FG know how this is supposed to look? > Obviously, if you would do it manually, you would blend the individual > ground texture against the surrounding. This is exactly how I'd do it. > Which is bad, because it means you > need non-local information to get the task done. I don't get this yet: why is blending the texture against the surrounding bad, and what's the problem with non-local information? > You'd also want to > generate different patterns in Europe, the US, Asia,... Yes, I'd be happy to generate different patters for different countries. If the code supports it, artists will step in here. > No, resolution will in fact go much down because of the memory limit. In > the current scheme using a finite set of terrain textures with procedural > overlays, we can achieve cm-sized resolution on ground features. Great. Can we have overlays for a finite set of buildings? > In the end, if I could make a wishlist how to design the scenery rendering, > I would probably separate hires sharp features like roads out and describe > them via vertices and pass the informtion on landclass distribution via a > meta-texture with relatively coarse resolution and build the actual > textures procedurally everywhere based on the relative distribution > densities of features coming from the meta-texture. Unique buildings would > then need to be registered on the meta-texture in the scenery generation > stage, the actual procedural terrain cover would be generated runtime on > the GPU. Sounds like a good plan to me. As for the Intel graphics argument, I'm with Gene. Cheers, Tom ------------------------------------------------------------------------------ Everyone hates slow websites. So do we. Make your web apps faster with AppDynamics Download AppDynamics Lite for free today: http://p.sf.net/sfu/appdyn_d2d_mar _______________________________________________ Flightgear-devel mailing list Flightgear-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/flightgear-devel
