Abstract: A method and apparatus provides context switching of logic in an integrated circuit using one or more test scan circuits that use test data during a test mode of operation of the integrated circuit to store and/or restore non-test data during normal operation of the integrated circuit. The integrated circuit includes context control logic operative to control the test scan circuit to at least one of: store and restore context state information contained in functional storage elements in response to detection of a request for a change in context during normal operation of the integrated circuit.

Abstract: A multi-chip module as disclosed herein includes a first semiconductor device, a second semiconductor device and a plurality of device interconnect members. The first semiconductor device is capable of enabling functionality associated with a first circuit segment of an integrated circuit design and includes an array of first device interconnect pads. The second semiconductor device is capable of enabling functionality associated with a second circuit segment of the integrated circuit design and includes an array of second device interconnect pads. Each one of the device interconnect members is electrically connected directly between one of the first device interconnect pads and a corresponding one of the second device interconnect pads.

Abstract: A method and apparatus for synchronizing the execution of a sequence of graphics pipelines is provided. For a representative embodiment a sequence of graphics pipelines are connected in a daisy-chain sequence. Each pipeline operation can be controlled to operated in one of two modes. The first is a local mode where the pipeline outputs its own digital video data. The second is a pass-through mode where the pipeline outputs digital video data received from preceding graphics pipelines. The pipelines are configured to allow an application executing on a host process to select the next pipeline that will enter local mode operation. The pipeline that is selected to enter local mode operation asserts a local ready signal when it is ready to begin outputting its digital video information. Each of the pipelines monitors the state of a global ready signal. When the global ready signal becomes asserted it means that the pipeline that is selected to enter local mode operation is ready.

Abstract: A system and method of interactively generating computer graphic images for incorporating three dimensional textures. The method of the present invention includes defining an orientation of a polygon relative to a plurality of three dimensional (3D) texture data sets, determining a level of detail of a pixel associated with the polygon, and selecting a first 3D texture data set and a second 3D texture data set from the plurality of 3D texture data sets in accordance with the pixel level of detail. The method also includes mapping the pixel to a first position within the first 3D texture data set and to a second position within the second 3D texture data set in accordance with the orientation, and generating a display value for the pixel in accordance with the mapping of the pixel to the first and second positions.

Abstract: An apparatus and method for interactively magnifying a base texture to generate a generally unblurred magnified image of the base texture is disclosed. The present invention includes a base texture generator for filtering a high resolution source image to generate a base texture. A detail texture generator extracts a representative portion of high frequency information from the source image to generate a detail texture, wherein the detail texture comprises the extracted representative portion of high frequency information. An image magnifier, which is coupled to the base texture generator and the detail texture generator, augments the generated base texture with high frequency information from the detail texture to thereby generate a magnified image of the generated base texture at a particular level of detail.

Abstract: A system and method of interactively magnifying a first texture to generate a generally unblurred high resolution display image at a particular level of detail are disclosed. The method of the present invention includes the step of extrapolating from the first texture and a second texture to generate an extrapolated frequency band. The extrapolated frequency band approximates high frequency image information contained in a texture of higher resolution than the first texture. The method also includes scaling the extrapolated frequency band as a function of the particular level of detail to generate a scaled extrapolated frequency band, wherein the scaled extrapolated frequency band approximates high frequency image information contained in a magnified image of the first texture at the particular level of detail.

Abstract: The effect of multi-layer atmospheric scattering on the visibility F of each point P on a visible surface of each polygon in a display scene, in a computer image generation (CIG) system, is provided by determining the effective average reciprocal half-fading distance between viewpoint and the viewed point, knowing the altitudes at which each of the different scattering layers start and accounting for any transitional slopes therebetween. The total reduced visibility of that viewed point P is a function of the average reciprocal half-fading distance for that point and of the total range between the viewed point P and the viewpoint VP.

Abstract: A method for determining the proper occulation relationship between a calligraphic point and at least one of another calligraphic point and a surface in a raster image, divides the total image screen into an array of spans, each containing an ordered set of pixels which may be further divided into an array of subpixels; determines which of the subpixels on the total screen lie inside each of the raster surfaces and calligraphic points which must be considered for the image totality; then orders the distance of each of the raster surfaces from the viewing point and also orders the distance of each of the point features from the viewing point; and then compares the ordered distances of each point to at least one of the raster surface distances and other point distances to determine which of subpixels of the point or surface/other point are occluded and which subpixels are visible.

Abstract: A method for determining the illumination of an illuminator at a selected point P in an image volume to be projected on an image screen surface by a computerized image generator, operates by: decomposing the illuminator into at least one of spherical, beam and cylindrical sources; determining a direction of incidence of the light from each source at point P in the image volume; determining the extent of the source and the attenuation of illumination with distance from that source; then determining a set of color light intensities at point P in the image volume due to the light from the particular source; and translating the incidence direction and color intensities from point P to a displayable incidence direction and a displayable set of color illumination intensities at a corresponding projection location on the image screen surface.

Abstract: The values of an attribute, like color, to be assigned to the right and left half of a pixel of a display device, such as may be determined by a computer image generation system, are compared for determining a difference value. If the difference value is less than a predetermined threshold, an average of the left and right half values is assigned to the pixel. If the difference value is greater than or equal to the threshold, then the right and left half values are assigned to the respective right and left halves of the pixel and during the raster scan, the attribute value of the pixel to be displayed is transitioned at the beginning of the pixel interval and in the middle of the pixel interval so that the pixel presents an image in response to the corresponding right and left half values. The data for the left and right half values may be truncated and stored as a portion of the data word or may be encoded into logarithmetic form having a mantissa and shift code.

Abstract: In a computer image generation system, as a viewpoint approaches a surface of an object and is closer than a predetermined threshold distance from the surface, a texture pattern obtained from cell data becomes fuzzy, and may not provide adequate motion cues for training, such as piloting an airplane. In accordance with the present invention, apparatus and method provide random data at a predetermined derived level of detail for combining with cell data to define the surface including texture of the object when the object is closer to the viewpoint than the threshold distance. The apparatus may be readily retrofitted into an existing system.