• Journal of the Korea Computer Graphics Society
• /
• v.26 no.3
• /
• pp.69-77
• /
• 2020

This paper proposes an effective method of giving users feedback on 3-dimensional drawing and measures its performance to ensure that feedback can help users enter the correct position in 3D. In the experiment of drawing a given line shape using a hand-held controller, the user is provided with three levels of visual, auditory, and haptic feedback for the position input error. As a result of analyzing the position input accuracy according to the type of feedback, all types of feedback are able to significantly reduce errors, and visual feedback and haptic feedback are more effective than auditory feedback.

• Journal of Industrial Technology
• /
• v.19
• /
• pp.173-178
• /
• 1999

In many areas of technology there are machines and systems controllable in up to six degrees of freedom. Helicopters and underwater vehicles, industrial robots are among the first representatives of this category. They need six degrees of freedom in order to move and orient within their workspace. An even broader and more explosively growing area is 3D computer graphics and virtual environment. In this work, functions of 3D input device are described and two types of commercial 3D input device are presented. Then, a preliminary experiment of a low cost 6 axis force/moment sensor is presented that can also be sued as a 3D input device. A low cost force/moment sensor and its application in robot teaching experiment is described. It computes the direction of 3 components of the force and 3 components of the moment applied by human holding the sensor by hand. The concept is shown by an experiment where the tool position and orientation of a robot in 3 dimensional space is controlled by the proposed sensor.

• The Journal of the Korea Contents Association
• /
• v.11 no.11
• /
• pp.19-27
• /
• 2011

In this paper, we present an emulation library for the essential features and their API function calls provided by Direct3D, the most actively used API for computer game-related application programs on the MS-Windows-based desktop's, with OpenGL library in the Linux environment. In typical Linux-based systems, only the X window system and OpenGL graphics library are available. There are lots of needs for this kind of emulation library to convert the Direct3D-based game applications and user interfaces on these systems. Through carefully selecting the essential API functions from the DirectX version 9.0, we obtained the prototype implementation of that emulation library, to finally get the final full-scale DirectX implementation. Our implementation currently covers 3D coordinate transformations, light and material processing, texture mapping, simple animation features and more. We showed its feasibility through successfully executing a set of Direct3D demonstration programs including a real-world game character animation on our implementation.

• Journal of the Institute of Electronics Engineers of Korea CI
• /
• v.43 no.6 s.312
• /
• pp.71-82
• /
• 2006

For real-time animation, keyframe animation that consists of translation, rotation, scaling transform nodes is used widely in 3D graphics. This paper presents geometrical watermarking using vertex coordinates in CoordIndex node and interpolator watermarking using keyvalues in PositionInterpolator node for 3D keyframe animation based on VRML. Experimental results verify that the proposed algorithm has the robustness against geometrical attacks and timeline attacks as well as the invisibility.

• Journal of Sensor Science and Technology
• /
• v.16 no.2
• /
• pp.110-114
• /
• 2007

In this paper we present 3-D Navigation View, a three-dimensional visualization of indoor environment which serves as an intuitive and unified user interface for our developed indoor location tracking system via Virtual Reality Modeling Language (VRML) in web environment. The extracted user's spatial information from indoor location tracking system was further processed to facilitate the location indication in virtual 3-D indoor environment based on his location in physical world. External Authoring Interface (EAI) provided by VRML enables the integration of interactive 3-D graphics into web and direct communication with the encapsulated Java applet to update position and viewpoint of user periodically in 3-D indoor environment. As any web browser with VRML viewer plug-in is able to run the platform independent 3-D Navigation View, specialized and expensive hardware or software can be disregarded.

• The KIPS Transactions:PartA
• /
• v.16A no.3
• /
• pp.153-158
• /
• 2009

Analysis of 3-dimensional (3D) protein structure plays an important role of structural bioinformatics. The protein structure visualization is the one of the structural bioinformatics and the most fundamental problem. As the number of known protein structure increases rapidly and the study of protein-protein interaction is prevalent, the fast visualization of large scale protein structure becomes essential. The fast protein structure visualization system we proposed is sophisticated and well designed visualization system using geometry instancing technique. Because this system is optimized for recent 3D graphics hardware using geometry instancing technique, its rendering speed is faster than other visualization tools.

• Journal of the Korea Computer Graphics Society
• /
• v.27 no.5
• /
• pp.1-11
• /
• 2021

The purpose of our research is to efficiently deform a 3D models which is composed of a triangular mesh and a skeleton. We designed a novel inverse kinematics (IK) solver that calculates the updated positions of mesh vertices with fewer computing operations. Through our user interface, one or more markers are selected on the surface of the model and their target positions are set, then the system updates the positions of surface vertices to construct a deformed model. The IK solving process for updating vertex positions includes many computations for obtaining transformations of the markers, their affecting joints, and their parent joints. Many of these computations are often redundant. We precompute those redundant terms in advance so that the 3-nested loop computation structure was improved to a 2-nested loop structure, and thus the computation time for a deformation is greatly reduced. This novel IK solver can be adopted for efficient performance in various research fields, such as handling 3D models implemented by LBS method, or object tracking without any markers.

• Journal of the Korea Computer Graphics Society
• /
• v.8 no.1
• /
• pp.1-11
• /
• 2002

In order to widely use volume rendering technology in practical fields, a user should be able to control the classification parameter interactively and extract a meaningful information easily from the 3D data as fast as it can be. Previous work on an accelerating volume rendering reconstructs an isotropic volume from an anisotropic one and classifies in pre-processing time and then renders the classified volume rapidly in run time. But, this traditional step may result in long pre-processing time and no real-time feedback. In this paper, we present an efficient classification and rendering method that allows a user to set the opacity transfer function interactively at rendering time on a personal computer without special-purpose hardware.

• Journal of the Korea Computer Graphics Society
• /
• v.14 no.2
• /
• pp.35-41
• /
• 2008

H-Anim is an international standard that Humanoid Animation Working Group in Web3D Consortium defined the data structure necessary for human animation. Various libraries and tools have been generated according to the structure, but they still have restrictions to represent realistic humanoid motions. This paper presents the method of generating realistic human motion using motion capture data in order to define motion for humanoid animation based on H-Anim standard. In order to implement this, we have defined a data structure capable of receiving motion capture data and implemented a motion browser. The human motion data structure defined in this paper is based on X3D and intended to have compatibility through networks and various browsers.

• Journal of the Korea Computer Graphics Society
• /
• v.24 no.4
• /
• pp.39-54
• /
• 2018

Recently, augmented reality(AR) based building information applications using a smart phone provide information in the static form irrespective of the distance between a user and a target building. If many target buildings are located close to each other, discrimination of information is reduced due to overlapping information objects. Furthermore, it is difficult to intuitively grasp the current position of the user in the previous AR-based applications. In this paper, to solve these limitations, we have designed and implemented a novel building information system in which the location and size of information objects are adaptively displayed according to locations of a user and target buildings, and which allows users to intuitively understand their location by providing a 3D map that displays the user's location and all target buildings within a given distance in real-time. The AR-based building information application proposed in this paper focuses on the building guide in Deoksu Palace in Jung-gu, Seoul.