This paper proposes the method of soft shadow generation by extending the shadow volume to generate outdoor 3DCG images. In our method, two parameters, “brightness of shadow” and “soft shadow range”, are introduced to enable various soft shadows in different time zones. This algorithm aims to mount our method onto portable devices, so that the shadow texture for a soft shadow is generated and a soft shadow can be generated with the processing that does not depend on hardware specifications.

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In positioning of the present art pieces, the irreversible restoration for beauties recovery is not allowed in many cases. In this research, we applied augmented reality technology to this problem, and the virtual restoration method of the art piece in the real world is proposed. In this proposed method, the correction image for restoration is generated from a non-damage image scanned in advance. As the method to recover the beauty, the marker tracking is used to detect art piece position and the correction image is projected from calibrated LCD projector. Moreover, the pose of art piece is detected and luster restoration is performed based on the phong model. In the experiment, the color restoration and luster restoration by a sample image were performed. From the experimental results, the ability of restoration of the discoloring and luster was confirmed in the real world imaginary by the correction image projection.

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In this paper we present our solution for shadow generation, visibility sorting and GPU based shading of translucent point data for point based rendering. Our Translucent Shadow Mapping Algorithm uses a spherical coordinate system and solves the distancebased sorting, transparency calculation, shadow mapping, omni-directional mapping and light intensity attenuation problems in one step. We also propose a novel algorithm for visibility sorting of unstructured point data using the Hierarchical Bucket Sorting approach. This algorithm uses less memory and produces precise back-to-front ordered slices compared to previous methods. Finally, the shading calculations are performed in the GPU, using the rendering-oriented attributes of the point splats. Furthermore, we demonstrate the efficiency and flexibility of our novel approach of point splatting by showing several rendering results for visualizing mixed 3D data sets.

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The difficulty of puzzle rings is mainly due to the complexity of the solving procedures and the dimensions of the possible moving paths. This paper aims at quantitative evaluation of the puzzle ring difficulty. We propose some feature values to express the difficulty. Then, effectiveness of those values is evaluated by comparing with how difficult we feel when we solve real puzzle rings. To be solved puzzle rings by the computer, we have implemented data structure to express puzzle rings and algorithms to manipulate them. The search algorithm to find the optimal path and a method for characterizing the configuration space are presented.

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