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Background PhotoWizardİ Introduction TerraBuilder's PhotoWizard is a quick and easy method to convert aerial and satellite imagery into MS Flight Simulator-series scenery (Flight Simulator 98, Combat Flight Simulator and Flight Simulator 2000) TerraBuilder processes the imagery by slicing it into "chunks" that, among other things, contain texture slices of 256x256 pixels in size. Each chunk contains properties that can be modified on individual basis. Each chunk is sized and positioned according to the limits of the overall scenery given by user during the creation process. Another property of the chunk is that it is a grid of variable density, which can be set on individual basis. Each grid intersection ("grid node") can be given an altitude value, thus giving a chunk 3-dimensional, landscape properties. This is accomplished by inserting an Altitude Map (AM) which is simply an array of altitude values that covers a finite area. Think of elevated mesh scenery as a blanket which you can pinch up or push down in order to create hills and valleys. In order to do this, you will need a "blanket": this is called terrain texture map. Also, designer will need to know "where to pinch and push" the blanket: this is called "terrain altitude map". Once these two resources have been provided, designer must provide a few additional parameters: where and how big the terrain is, and how well defined, or dense, the mesh should be. Once this is known, TerraBuilder assigns grid to the terrain texture map, and at every intersection of grid line it looks up to the corresponding position in altitude map and assigns height, or altitude, of that grid point. In TerraBuilder altitude map can be defined in several ways. The simplest way (and the only option in LITE version) is through a grayscale bitmap, where each pixel in the bitmap represents one altitude point. The intensity of the pixel defines level of altitude: Dark pixels are low areas, bright pixels are high areas. Since the altitude bitmap does not tell you absolute altitudes, designer will also need to supply the maximum and minimum altitudes that the altitude bitmap represents. Therefore, the darkest gray (usually black) will be the lowest specified altitude, and the lightest gray (usually white) will be highest specified altitude. |