In recent years, with the development of computer games, game AI has been actively studied. The path search and tracking are important functions of game AI. In this research, we propose a method to realize tracking algorithm of character AI in arbitrary map using wave equation. The tracking algorithm in the game AI is often realized by applying various theories for route search. However, there is a problem that it takes time and effort to construct a graph network constituting the route and calculate the cost of each node. In this method, it is possible to set only the penetration possibility at grid points in space as preparation, and it is possible to easily find the shortest path to the destination. Furthermore, it has the advantage of not requiring any additional processing when dynamically changing the map.

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Petaloid smocking is a handcraft technique of constructing flower shapes over the surface of cloth based on sewing and pleats. However, since cloth is too flexible to sustain the shape, it is not easy to construct desired shapes on cloth by flattening and arranging pleats generated via sewing. Toward supporting the construction of petaloid smocking, we propose to generate strings for petaloid smocking based on its crease pattern. Based on the constraints on how pleats should be flattened according to the crease pattern, we propose algorithms to generate strings for enforcing the folding of pleats. The proposed method is implemented using GeoGebra, and applied to the design of a bag with strings. The generated strings were effective to transform the shape of the bag with petaloid smocking.

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We propose a method to generate dynamic projection mapping for leaves by automatically tracking the projection areas and the image registrations of projection areas. Recently, the targets of projection mapping have included various objects ranging from buildings to fish. However, it is difficult to project onto dynamic and deformable objects, such as leaves. Therefore, our system reduce effort during a projection by the semi-automatic image registrations. And our system registers images for dynamic and deformable object by tracking without any 3D model and markers. We achieve automatic generation of projection mapping for various leaves mainly oval ones. And we create interactive art works by projecting three effect animations which are generated automatically. Then, we displayed our works at a conference and an exhibition, and our work was evaluated by the experiencers and the judges.

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To render fluorescence, a wavelength dependent phenomena, we need to take into account the spectral distribution of light. Moreover, for translucent fluorescent medium we need to consider subsurface scattering. We propose a spectral rendering method to render fluorescence on translucent materials under global illumination environment. The proposed method is based on the physical properties of the fluorescence phenomena and rendered in a Probabilistic Progressive Photon Mapping method. By separating the power of photons into 3 elements (fluorescence, single scattering, multiple scattering), our method realizes fluorescence taking into account the scattering and absorption of light under the surface. We also introduce the Photon Power Table used for calculating the illuminance efficiently and deciding the outgoing point of light probabilistically. Finally, we show the usefulness of our method by demonstrating the rendered image.

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In recent animations, we can find fluid-like effects that stretch. We call these effects "blobby". Blobby is drawn by hand. Therefore, it is tedious to generate blobby and it requires skilled animator, and it is hard to fix it once blobbies are generated. Thus, we propose a method to generate blobby as pseudo elastic body and two kinds of control methods for blobby. Our method applies metaball to render blobby's characteristics. As a result, our method enables to easily generate exaggerated fluid style which is unique effects of hand-drawn animation.

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Display of images/videos on a big screen/display, such as digital signage, projection mapping, etc., is becoming popular in the area of entertainment, advertisement and so on. Comparison of the usage of an LED display and a projector is important for such applications. We have prepared experimental environment where two types of projection/display using a 200 inch LED display and a 200 inch screen and a projector. Also, two brightness conditions, light-on and light-off, and two types of contents, art content and text content, were used for the experiment. Under totally eight types of environments, we carried out a psychological experiment using 24 participants. Each subject filled a questionnaire based on five-point semantic differential scale. For the obtained results, firstly, the comparison of mean value of 5 grade scores was carried out and it was revealed that the combination of art content, light-off, and LED display gives far better results than other combinations. Next, to know more detailed analysis results, three-way ANOVA was carried out. And it was revealed how the three factors (LED display/projector, light on/off, art/text content) influence each other.

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"Spatial augmented reality (SAR)" or "projection mapping" projects an image of a virtual object on the surface of a real object. A "view-dependent" display shows the virtual object with its correct appearance for an arbitrary viewer's position. If the virtual object and the real object have different shapes, the virtual object's image to project needs to be correctly distorted according to the viewer's position. Besides, the difference causes the real object's surface to have some empty areas onto which the virtual object is not projected. Such empty areas seriously degrade the viewer's feeling that the virtual object merges into the real world. We propose a method to eliminate undesired empty areas by projecting the real background behind the real object in a view-dependent way. Our method converts a real background's image captured by a fixed camera to an appropriate image for a viewer's position based on homography. This image conversion approximates the background's shape by a plane adjusted for an arbitrary viewer's position. The plane is determined by practical parameters interpolated on a 3D grid space. Consequently, the viewer does not feel the presence of the real object and feels the virtual object merging into the real world.

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