Abstract: Geometric data for a three-dimensional surface are compressed in regard to the data representing the continuity between triangles in a mesh that represents the three-dimensional surface. The geometric data include information defining the vertices of the triangles comprising the mesh, an indication of the triangle faces, and corner normals to each of the vertices shared by triangles having a common vertex, which indicates the continuity or discontinuity between adjacent triangles of the surface. Vertex rotation continuity (VRC) data are determined for each vertex shared by adjacent triangles, indicating whether the transition between the adjacent triangles is continuous or discontinuous. Further, a dihedral angle between each pair of adjacent triangles is determined and associated with the VRC bit. The VRC data are sorted by the associated dihedral angles, enabling an optimal dihedral angle to be selected.

Abstract: Disclosed are a system and method for providing a three-dimensional graphic-user interface operator experience real-time feedback to modification to three-dimensional objects projected onto a computer display screen. Three-dimensional data is modified in surface space and then transformed from surface space to object space and then transformed again so that it can be projected to screen space. In transforming from surface space to object space, the data is characterized so that appropriate steps can be taken to cause the transformation.

Abstract: The present invention describes a circuit for performing high speed forward Scaled Discrete Cosine Transform (SDCT) and inverse Scaled Discrete Cosine Transform (ISDCT) in pipeline architecture which is ideally, but not exclusively, used for compressing and decompressing large volume image data in real time. A high throughput of image data transform and inverse transform is achieved with a relatively slow internal clock. The four stage pipeline architecture of the present invention requires no more than five multipliers in rendering either the forward SDCT or inverse SDCT coefficients. The lower-order SDCT's for either the forward or the inverse direction are imbedded in the higher-order forward SDCT or inverse SDCT respectively. By taking advantage of the recursive properties of the SDCT's, a larger size SDCT can be always implemented by using a combination of variants of smaller size SDCT.

Abstract: A data processing system directed to the preparation of complex forms. The system integrates a powerful graphics based form generator with embedded, form-specific logic and provides output of a form Specification Report. The system operates in an interactive manner allowing the user to review modifications to the form as it develops. The system then accesses embedded logic for selecting industry standards default values, compares the user modifications or set-up attributes to the industry standard values, and if need be, augments the user modifications or set-up attributes consistent with the industry standards for form production. Upon completion, the form includes specifications required to control a high speed printing operation. Various ancillary functions are provided, such as programmed strike positions for controlling subsequent fill-in by computer.

Abstract: Each object in a 3-dimensional image to be displayed may be represented by a set of infinite surfaces. Each elementary area of a screen on which the image is to be displayed has a ray projected through it onto the 3-dimensional image. The location of the intersection of the projected ray with each surface is then determined and from these locations it is determined whether any intersected surface is visible at that elementary area. The elementary area is then shaded for display in dependence on the result of the determination.

Abstract: A method for manipulating notes on a screen of a computer display characterized by: (a) generating an initial note area; (b) dividing the initial note area into a plurality of note areas in response to at least one division gesture implemented by a pointing device, where each division gesture creates a header bar, including function buttons, on the computer display which visually separates two adjacent note areas; (c) modifying the size of a selected note area in response to a sizing gesture made to a header bar; and (d) scrolling in at least one note area in response to a scrolling command. Step (b) includes the steps of detecting a division gesture made on the computer screen by a pointing device, and then creating a header bar at a location indicated by the division gesture. Step (c) includes the steps of detecting the selection of a header bar with a pointing device, detecting a subsequent sizing gesture made by the pointing device, and moving the header bar as indicated by the sizing gesture.

Abstract: An isosurface is composed of grid points having a predetermined scalar value. The method and apparatus of the present invention generates an isosurface by extracting from volume data a first grid point having a minimum scalar value and a second grid point having a maximum scalar value. A list of polyhedrons that intersect a line connecting the first grid point to the second grid point is generated and stored. The isosurface is generated in accordance with the list of polyhedrons and the predetermined scalar value. Because the volume data obtained by scientific and technological calculation or the like is kept in the form of a polyhedron list having an associated maximum scalar value and minimum scalar value, generating an isosurface according to a predetermined scalar value can be accomplished at high speed.

Abstract: A method and apparatus for formatting a document and creating a best document layout from an input list of picture and text objects is disclosed. The method includes calculating multiple document layouts while maintaining the correct reading order of the picture and text objects at all times. The method positions each picture and text object at multiple anchor points to create multiple document layouts, and then selects a best document layout which is the layout using the least number of pages to display the entire list of objects. If more than one layout uses the least number of pages, the layout positioning the least number of objects on the last page is the best layout.

Abstract: A data processing apparatus includes a graphics display device for displaying a display frame comprising a plurality of display frame pixels. A sprite management system composes the display frame from a plurality of graphic sprites. Each graphic sprite comprises a plurality of sprite pixels and corresponding sprite pixel values. Each sprite has a specified depth relative to the other sprites. One of the sprites is designated to be a video sprite. This sprite is loaded with a chroma-key value. The sprite management system includes a data processing device connected to access a display frame composition buffer. The data processing device is programmed to write pixel values of individual sprites to the display frame composition buffer. This writing begins with the pixel values of the sprite having the greatest depth and proceeds with the pixel values of the remaining sprites in order of decreasing sprite depth.

Abstract: A method for rendering a graphics image of a three-dimensional graphics model is described.

Abstract: A method and system for generating an anti-aliased image of a three dimensional surface is described. A point of view of the display screen is specified by an azimuth angle and an elevation angle with respect to the three-dimensional surface. The surface is defined as a two-dimensional array of height values. The projection of a point of the surface to the display plane is performed by applying a rotation based on the azimuth and elevation angles, followed by a parallel projection to the display plane so that, the columns of the surface project to the columns of the display screen. The points of the surface are projected in pairs, starting with the nearest points within a column and proceeding to the farthest points of the column. The grey-level shading (or color) values are accumulated in a one-dimensional array of floating-point variables that store the intensities of the pixels of a column of the display screen.

Abstract: This is a method for physically-based modeling of three dimensional (3D) general fluid animation in computer graphics. By solving the two dimensional (2D) Navier-Stokes equations using a Computational Fluid Dynamics method, we map it into 3D using the corresponding pressures in the fluid flow field. The method achieves realistic real-time fluid animation by solving the physical governing laws of fluids but avoiding the extensive 3D fluid dynamics computation. Unlike previous computer graphics fluid models, our approach can model many different fluid behaviors by changing the internal or external boundary conditions. It can also model different kinds of fluids by varying the Reynolds number. In addition, we have generated several ways to view the animation of fluid flow field, the streakline of the flow field and the blending of fluids of different colors. Our model can serve as a testbed to simulate many more fluid phenomena which have never been successfully modeled.

Abstract: A graphic display system has a display unit, a main memory for storing graphic data and a controller for controlling the processing and transferring of data between the display unit and the main memory. The main memory includes a correspondence table of luminance and color resource identifiers (IDs), image data based on color resource IDs, luminance-pixel position data, luminance-color data and combinational data of luminance-pixel position and luminance-color data. Differing images having either the same shape and different colors or the same color and different shapes are produced, according to the combinational data.

Abstract: A method for determining which objects are visible in each pixel of a digitally-generated image is described. The method uses comparison of distances from the viewpoint (Z-sorting) for occlusion. The number of Z comparisons required is minimized by utilizing a hierarchy of regions in the screen area, and thereby, resolving occlusion for areas larger than pixel areas where possible. Use of the area hierarchy increases the efficiency of the occlusion processing. In a preferred implementation, the screen is divided into equal-sized horizontal regions each corresponding to typically four scanlines. Polygons for each image are subdivided into pieces that correspond to the preset hierarchy of regions, and occlusion processing occurs independently in parallel for two or more regions. Each region is subdivided further into smaller regions, each level of the hierarchy having regions half the size of a higher level region.

Abstract: Digital signals defining a bit mapped primary image are stored in a data processing system and displayed on a color monitor. These signals are processed by breaking down or separating the primary image into a set of areas where the pixels within each area have the same color. The set of areas is then analyzed to select a group of a minimum number of subgroups, which group contains all of the different areas. Different color/dither patterns are assigned to represent the different subgroups. Then, a derivative bit mapped image is produced in which the assigned representations are used, and the derivative image is then printed or displayed.

Abstract: A graphic display apparatus includes a geometry transforming part for inputting graphic data of a target object and transforming the graphic data into coordinate values of a device coordinate system which is used by the graphic display apparatus, an area calculation part for calculating an area of a polygon which generates an image based on the transformed coordinate values of the device coordinate system, a shading technique selection part for selecting a shading technique corresponding to the area of the polygon calculated by the area calculation part from a plurality of shading techniques which are determined in advance depending to the calculated area, a luminance calculation part for calculating a luminance of the graphic data of the target object according to the shading technique selected by the shading technique selection part, and a dot developing part for developing the graphic data of the target object for which the luminance is calculated by the luminance calculation part into dots.

Abstract: Portions showing greater specular reflection of an object to be displayed are displayed with pixels whose opacity, .alpha..sub.1, is emphasized according to the specular reflected component of a shading model, in which case the specular reflected component thus calculated for shading is also utilized for arithmetic operation of emphasized opacity, .alpha..sub.1, and high-speed processing is sought through tabulating various variables such as .alpha..sub.s (an additional opacity introduced for emphasis by a specular reflected component), .alpha..sub.n (a primary opacity), and G (a gradient vector).

Abstract: A color palette mapped to an image obtained by any known process is decomposed to separate contrast components from hue/saturation pairs, then only the hue/saturation pairs are remapped to a new set of hue/saturation parameters according to available mapping techniques, including remapping of ordered color sets, into a new ordered set wherein at least a portion of the contrast components are held at fixed values and not altered. By fixing the contrast components, color remapping is constrained to certain symmetric transformations in Munsell color space which preserves features of the source image in the resultant image.