Physically based fluid simulation is one of the most important research topics in computer graphics.Although many methods have been developed that use 3D or 2D grids to simulate fluids,there are few methods for simulating fluid flows on surfaces.We present a real-time particle-based simulation method for the flows on surfaces.The surfaces are parameterized in a 2D parameter domain and physical quantities of particles are calculated in the parameter domain.The flows are simulated by updating the physical quantities of the particles,and the simulation is accelerated with a GPU.Our method simulates the fluid flows of 30,000 particles in real-time.

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We introduce a non-photorealistic rendering technique for transforming an input photograph into a maze-like scratch image.Stripe patterns are generated on the input image with an anisotropic shock filter,and then the edges of the stripes are extracted and thickened.These thickened edges are overdrawn on the input image to produce a maze-like scratch image.Three-dimensional (3D) effects are then added to the maze-like image using bump mapping.The displacement of edges produces a pop-up effect on the maze-like scratch lines.

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We present a non-photorealistic rendering (NPR) method that is suitable for generating stained glass-like images.Conventional Voronoi tessellation (VT) is extended to bilateral VT (BVT), which preserves main edges in the original image.We also present bilateral centroidal Voronoi tessellation (BCVT) as a way of closely simulating the original appearance of the input image.This method has also been used to transform several example photographs into their stained glass-like images.

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In human-scale virtual environments with a haptic interface, users can perceive depth information from both stereoscopic view and the haptic sensation provided by a haptic interface. Despite the high accuracy of the depth information from the haptic interface, users often get confused because of errors resulting from a lack of stereoscopic factors in the depth information of the view. In this paper, we introduce a correction method for improving visual depth perception in a human-scale virtual environment that provides haptic sensation. In this paper, we also discuss our experimental results and a practical application with our proposed method.

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We have developed a digital image editing system that can be operated intuitively.In our system,the target image is projected onto a back projection screen,and the user retouches the image using an infrared lighting device.The quantity of infrared light hitting each part of the screen from the lighting device is captured by a CCD camera,and the image is edited according to the quantity of captured infrared light.This system makes it possible to process images directly and intuitively.Moreover,it allows two or more people to edit the image at the same time.

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In this stady,all processes required to simulate the image reconstruction of a computer-generated hologram were conducted.Simulation of the reconstructed image of a full color rainbow hologram was successfully carried out.In a previous study,the reconstructed wavelength of the light used in the simulation consisted only of RGB.Therefore,the reconstructed image of white light was only possible when the simulation was done in the proper observation position.When the observation position was moved,the simulation could not be done.In this paper,we propose a method of continuous wavelength simulation that makes it possible to simulate a reconstructed image from any observation position.

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We have proposed an improved color control method for a projector-based color simulator.We use low dimensional response,which is measured with an RGB colorimetric camera to estimate spectral reflectance.In our previous work,a color simulator with a projection image was controlled color change on the basis of the ink supply.By overlapping the controlled projection image based on the spectral reflectance,this simulator helps operator to adjust the color of print more accurately.However,measuring the spectral reflectance from every point on print is expensive.To decrease the cost of spectral measurement,we propose a way of estimating method for spectral reflectance.Only three bands responses were used to estimate the spectral reflectance for the projector-based color simulator.The projection image calculated by approximate spectral reflectance reproduces the color change of the print instead of ink supply.Our color simulator with a projection image matched color accurately;for 32 samples,the average color difference ΔE^*₉₄=1.05 and the maximum color difference ΔE^*₉₄=2.58.

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When certain conditions of an existing figure's physical shape and location are satisfied,we perceive contour lines or figures that do not exist.This phenomenon is called a subjective contour,and its study is highly relevant to the spatial interpolation problem.Our purpose is to propose an algorithm that simulates subjective contours from digital images.This model estimates the possibility of the existence of an illusory figure's contour that is perceived to be nearer than the image.The model then outputs a subjective contour when the value smoothly connects the gaps between figures and has continuity.This model is capable of handling contours of both closed and segmented lines and generates curved contours.After explaining the algorithm,we show several simulation results and discuss generated contour shapes and their problems.

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When utilizing land consisting of an archeological site,the Cultural Properties Protection Law in Japan obliges developers to carry out an archeological excavation and publish a report on the findings.Measured drawings of excavated artifacts are illustrated after they are measured with special equipment.Because the process of generating measured drawings requires a high level of skill and a lot of labor,there has been considerable discussion about the need to streamline the process.To generate a measured drawing of earthenware artifacts efficiently,we propose a method to automatically generate section lines from the features of the earthenware.The drawing parameters are extracted from real measured drawings to generate the same section lines.After that,section lines are generated from the features that are extracted from the measured drawing,based on the drawing parameter function.

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