Abstract: In a real-time computer-image generation system, processing resources for manipulating polygons that define objects are generally limited. This results in a trade-off with respect to the amount of detail to be displayed in an object versus the number and type of objects to be displayed. The value of a predetermined viewing criterion is used to determine when an object can be represented by a single polygon. The single polygon is rotatable about a predetermined number of axes for maintaining a predetermined relationship with respect to a view point. Since processing resources are saved by using a single polygon, additional objects and/or more detail may be included in a display.

Abstract: A real time computer image generation system incorporating comprehensive distortion correction in which a predistorted image is computed and placed on a projection raster prior to projection onto a view screen in order that the image as seen by a viewer appears correct. A method for implementing comprehensive distortion correction in real time utilizes fixed transfer characteristics of a projection lens coupled with scene by scene translation of each of a plurality of predetermined points from a projection raster to a location on a view screen. Each image is divided into a plurality of spans and the span corners are mapped from the projection raster to the view screen. The location of image vertices on the view screen are determined with respect to the viewer and the vertices are mapped to corresponding locations on the projector raster.

Abstract: A method for computer image generation simulated visual scenes for applications such as flight training. The processing to generate the image takes place in three sequential stages: Controller, Geometry Processor, and Display Processor. At any point in time, the stages are processing data for three consecutive scenes. Each scene is comprised of a plurality of faces. Processing prior to the Display Processor accomplishes clipping and perspective transformation of faces. The Display Processor then generates the scene with pipeline processing accomplishing four major tasks: span detection or windowing, span sequencing, mask processing, and color processing. The improved realism of the computer generated image includes application of area-times-color smoothing, using fractional face areas to improve scene quality and reduce quantizing artifacts.

Abstract: A computer video image generating system including a computer memory having three dimensional object data stored therein employs an advanced object generator for retrieving and processing the object data for output to a span processor for controlling the pixel-by-pixel video output signal for a video display. The advanced object generator includes a translucency processor, an edge-on fading processor, a level of detail blending processor and a bilinear interpolator for texture smoothing.

Abstract: A method for computer image generation producing simulated visual scenes for applications such as flight training, employing a comprehensive distortion correction to generate the image takes place in three sequential stages: Controller, Geometry Processor, and Display Processor. The Display Processor generates video to produce the desired scene on the raster of the display device. If the scene is projected through a wide-angle lens and/or is projected onto a curved screen, the combination of optical and geometric distortion presents a highly distorted scene to the viewer. The comprehensive distortion correction method produces a precisely predistorted scene on the projector raster so it appears valid to the viewer. Mapping between projector space and viewer space is highly nonlinear. However, a small region of the display (span) is selected sufficiently small so that the projector/viewer transformation may be considered linear.