A 5th generation SPARC64 processor is fabricated in 130nm SOI CMOS process with 8 layers of Cu metallization. It runs at 1.3GHz with 34.7W power dissipation in the laboratory. The chip contains over 190M transistors with 19M in logic circuits. The chip size is 18.14mm x 15.99mm. The error detection and recovery mechanism is implemented for execution units and data path logic circuits in addition to on-chip arrays to detect and recover from data logic error. This processor is developed by using mostly in-house CAD tools.

Iridescent colors appearing on natural objects, such as the feathers of a hummingbird, surfaces inside seashells, and shells of beetles, are beautiful and impressive. The cause of such iridescent colors is interference of light inside multilayer film structures covering the natural objects. The paper proposes a method for realistically rendering iridescent colors appearing on natural surfaces, taking into account interference of light inside multilayer structures. To render the iridescent colors, we have developed an illumination model for multilayer structures fluctuated through the use of a hypertexture. We also have improved the hypertexture to be able to represent fluctuated parametric curved surfaces. Several examples of iridescent colors on the surfaces of a seashell and a beetle demonstrate the usefulness of the proposed method.

This paper proposes a simple and computationally inexpensive method for animation of clouds. The cloud evolution is simulated using cellular automaton that simplifies the dynamics of cloud formation. The dynamics are expressed by several simple transition rules and their complex motion can be simulated with a small amount of computation. Realistic images are then created using one of the standard graphics APIs, OpenGL. This makes it possible to utilize graphics hardware, resulting in fast image generation. The proposed method can realize the realistic motion of clouds, shadows cast on the ground, and shafts of light through clouds.

This paper proposes a method for rendering objects coated with multilayer thin films. Multilayer thin films are widely utilized in industry for example, optical lenses, optical filters, and windowpanes, among others. Demand for visualization of the optical effects of multilayer films has therefore become great. To visualize optical properties of such films, we have developed a method for calculating composite reflectance and transmittance of the system of multilayer thin films, taking into consideration such factors as multiple reflection, interference and absorption of light inside the films. The proposed method is based on wave optics, and is able to accurately visualize the optical effects of multilayer films consisting of not only dielectric materials, but also metallic and semiconductive materials. Metallic and semiconductive materials are able to absorb light, and their refractive indices are expressed as complex values, Dielectric materials, on the other hand, do not absorb light, and the refractive indices are expressed as real values. Taking into consideration complex refractive indices, the proposed method can visualize optical phenomena caused by various kinds of multilayer thin films. The proposed method is implemented using a raytracer and optical properties of a SiO/sub 2/ film coating on a silicon base, and several kinds of multilayer films coating windowpanes or teapot are visualized to demonstrate the usefulness of the proposed method.

Rendering a scene containing water is among the most challenging aspects in the field of computer graphics. Researchers have developed a wide variety of algorithms for rendering water, but there still remain unaddressed problems due to water's multiformity and complex patterns of motion. This paper proposes a method for generating realistic animation of water droplets on transparent surfaces such as the windshield of a vehicle. One of the method's applications can be considered the animation of water droplets on a windshield, a process vital for drive simulators. The proposed method employs a particle system in a discrete environment to calculate the movement of water droplets on a surface, and environment mapping for indicating the property of transparency to quickly render scenes through transparent objects. Using the method, windshield wipers moving on a windshield and other obstacles moving against water droplets can also be taken into account. Fully computer-generated animations and video compositions of water droplets on a windshield demonstrate the usefulness of the proposed method. Copyright © 1999 John Wiley & Sons, Ltd.

The paper proposes an image based modeling of clouds where realistic clouds are created from satellite images using metaballs. The intention of the paper is for applications to space flight simulators, the visualization of the weather information, and the simulation of surveys of the Earth. In the proposed method, the density distribution inside the clouds is defined by a set of metaballs. Parameters of metaballs, such as center positions, radii, and density values, are automatically determined so that a synthesized image of clouds modeled by using metaballs is similar to the original satellite image. We also propose an animation method for clouds generated by a sequence of satellite images taken at some interval. The usefulness of the proposed method is demonstrated by several examples of clouds generated from satellite images of typhoons passing through Japan.

In contrast with the growth of plants and trees, human organs can undergo significant changes in shape through a variety of global transformations during the growth period, such as bending or twisting. In our approach, the topology of a human organ is represented by a skeleton in the form of a tree or cycled graph. The length of skeleton growth can be simulated by an algebraic L‐system that also produces discrete events. The paper shows how to include global transformations into the formalism of L‐systems to obtain a continuous process. The shape of the organ is approximated by a number of ellipsoidal clusters centred at points on the skeleton. The proposed growth model of the organ continually responds to the positional changes of surrounding organs, thereby changing the organ shape locally. In our study, the stomach of a human embryo is used for the demonstration of organ development, and the methodology employed is also applicable to the animation of animal organs and their development.

The paper reports a solution to the problem of image interpolation for generating, with high precision, an arbitrary cross-section from a series of slices. Shape-based interpolation as proposed allows the interpolation process to be influenced by the shape of the object. It is accomplished first by creating reconstructed shapes of the objects from a series of slices. Correspondence vectors distributed along the object surface are then generated from the reconstructed shapes. These vectors ensure the correct image interpolation on the boundaries of objects. Next, the correspondence vectors are interpolated to every image point within the new cross-section in process, and the image points at the start and end of a vector are linearly interpolated. Places where the correspondence vectors cannot be (branching or holes in the object shape) are treated separately. Results are presented from biological data obtained using an optical microscope. The data indicate that the proposed method produces more accurate results than commonly used interpolation methods, although at the cost of increased computation.

A parametric L-system (Lindenmayer system) is developed to model the growth and structure changes of human stomach over the time starting in the third week and going on into week four of human embryo development. The model takes into account what is known about embryo movement during growth. The framework uses the formalism of L-systems with constructs that are dependent on time and smooth growth functions. The method captures the development of human embryo stomach consistently with static observations of the real embryo. Computer animation and visual interpretation make it possible to understand the modeled processes accurately and lead to realistic exploration of the human stomach at various stages of development.

Computer graphics are being used for visual environmental assessment or architectural designs. Displaying the sky as a background is indispensable in generating photorealistic images for such applications. In this paper, we propose a fast display method of the sky colour by expressing the intensity distribution of the sky using basis functions, even if the sun position and/or the camera position are altered. In the proposed method, cosine functions are used as basis functions. The sun altitude is altered at certain intervals and the distributions of the sky colour for each sun altitude are precalculated and stored efficiently using basis functions. The colour of the sky in the view direction of an arbitrary sun position can be obtained from the stored distributions and displayed quickly. © 1997 by John Wiley & Sons, Ltd.

Abstract Recently, computer graphics are frequently used for both architectural design and visual environmental assessment. Using computer graphics, designers can easily compare the effect of the natural light on their architectural designs under various conditions, such as different times of day, seasons, atmospheric conditions (clear or overcast sky) or building wall materials. In traditional methods of calculating the luminance due to sky light, however, all calculation must be performed from scratch if such conditions undergo change. Therefore, to compare the architectural designs under different conditions, a great deal of time has to be spent on generating the images. This paper proposes a new method of quickly generating images of an outdoor scene, taking into account glossy specular reflection, even if such conditions change. In this method, luminance due to sky light is expressed by a series of basis functions, and basis luminances corresponding to each basis function are precalculated and stored in a compressed form in the preprocess. Once the basis luminances are calculated, the luminance due to sky light can be quickly calculated by the weighted sum of the basis luminances. Several examples of an architectural design demonstrate the usefulness of the proposed method.

Abstract When designing interior lighting effects, it is desirable to compare a variety of lighting designs involving different lighting devices and directions of light. It is, however, time‐consuming to generate images with many different lighting parameters, taking interreflection into account, because all luminances must be calculated and recalculated. This makes it difficult to design lighting effects interactively. To address this problem, this paper proposes a method of quickly generating images of a given scene illustrating an interreflective environment illuminated by sources with arbitrary luminous intensity distributions. In the proposed method, the luminous intensity ditribution is expressed with basis functions. The proposed method uses a series of spherical harmonic functions as basis functions, and calculates in advance each intensity on surfaces lit by the light sources whose luminous intensity distribution are the same as the spherical harmonic functions. The proposed method makes it possible to generate images so quickly that we can change the luminous intensity distribution interactively. Combining the proposed method with an interactive walk‐through that employs intensity mapping, an interactive system for lighting design is implemented. The usefulness of the proposed method is demonstrated by its application to interactive lighting design, where many images are generated by altering lighting devices and/or direction of light.

Abstract It is inevitable for indoor lighting design to render a room lit by natural light, especially for an atelier or an indoor pool where there are many windows. This paper proposes a method for calculating the illuminance due to natural light, i.e. direct sunlight and skylight, passing through transparent planes such as window glass. The proposed method makes it possible to efficiently calculate such illuminance accurately, because it takes into account both non‐uniform luminous intensity distribution of skylight and the distribution of transparency of glass according to incident angles of light. Several examples including the lighting design in an indoor pool, are shown to demonstrate the usefulness of the proposed method.

Abstract Photorealistic animated images are extremely effective for pre‐evaluating visual impact of city renewal and construction of tall buildings. In order to generate a photorealistic image not only the direct sunlight but also skylight must be considered. This paper proposes a method of high‐fidelity image generation for photorealistic outdoor scenes based on the following ideas: The intensity distribution of skylight taking account of scattering and absorption due to particles in the atmosphere which coincides with CIE standard skylight luminance functions is sought, and realistic images considering about spectrum distribution of skylight for any altitude of the sun can be easily and accurately displayed. A rectangular parallelepiped with a specialized distribution of intensity simulating the skylight is introduced for efficient calculation of illumination due to skylight, and by employing a graphics hardware calculation of the skylight illuminance taking into account shadow effects is obtained with high efficiency; these techniques can be used to generate sequences of images, making animations possible at far lower calculation cost than previous methods.

Abstract In order to observe the physical values (magnetic flux density and eddy current) in 3D magnetic field analysis, an interactive and highly manipulative visualization system depicting stereo images is intalled in a graphics workstation with high functional graphic processors. The system has the following characteristics: An interactive and highly manipulative menu window with many functions: it enables visualization of complex phenomena in a 3D field through observation of various combinations of physical values from various viewpoints. Simultaneous display of both magnetic flux density and eddy current by using the appropriate use of two colour display methods for stream lines and distribution maps of density: this function facilitates observation of the mutual relations between two physical values in a 3D field. Animations and stereo displays: since they give extremely distinct images, observers can easily understand even highly complex 3D phenomena. In this paper, the calculation method of density vectors, their display methods, and interactive functions are described. Some examples are also illustrated.

Computer graphics techniques for visualizing the following simulation results are developed: (1) lighting designs for different type sources such as point sources, linear sources, area sources, and polyhedron sources, (2) shaded time at arbitrary positions such as windows, walls, and even the inside of a room, (3) montages for view environment evaluation, (4) quasi-semi-transparent models for observing life generation process in anatomy, and (5) two and three dimensional magnetic fields analyzed by the finite element method.