• Journal of the Korea Computer Graphics Society
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• v.14 no.4
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• pp.7-18
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• 2008

To realistically produce fluids such as smoke for the visual effects in the films or animations, we need two main processes: a physics-based modeling of smoke and a rendering of smoke simulation data, based on light transport theory. In the computer graphics community, the physics-based fluids simulation is generally adopted for smoke modeling. Recently, the interest of the particle-based Lagrangian simulation methods is increasing due to the advantages at simulation time, instead of the grid-based Eulerian simulation methods which was widely used. As a result, because the smoke rendering technique depends heavily on the modeling method, the research for rendering of the particle-based smoke data still remains challenging while the research for rendering of the grid-based smoke data is actively in progress. This paper focuses on realistic rendering technique for the smoke particles produced by Lagrangian simulation method. This paper introduces a technique which is called particle map, that is the expansion and modification of photon mapping technique for the particle data. And then, this paper suggests the novel particle map technique and shows the differences and improvements, compared to previous work. In addition, this paper presents irradiance map technique which is the pre-calculation of the multiple scattering term in the volume rendering equation to enhance efficiency at rendering time.

• Proceedings of the Korean Society of Computer Information Conference
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• 2016.01a
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• pp.235-236
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• 2016

본 논문에서는 파티클 효과 응용에 대해서 나타낸다. 파티클 효과는 연기, 화염, 불꽃, 특수 효과를 이용하여 이러한 입자들을 표현하여 현실 세계에서 보다 더 현실감을 나타낼 수 있도록 한다. 본 연구에서는 이러한 파티클 효과를 적용함으로써 계절에 관계없이, 장소에 관계없이 콘텐츠를 제작하여 필요한 영상 분야나, 비디오 시각화 등 다양한 분야에서 사용될 수 있음을 나타내었고, 보다 많은 영역에서 특수 효과를 쉽게 연출 할 수 있음을 나타내었다. 따라서 실생활에서 다양한 파티클 효과를 재현함으로써 현실세계에서도 이러한 시뮬레이션을 구현 할 수 있음을 나타낸다. 또한 다양한 영역에서 콘텐츠로서 효과적으로 사용될 수 있다고 본다.

• Journal of the Korea Computer Graphics Society
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• v.2 no.1
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• pp.7-14
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• 1996

A particle system is defined as a collection of primitive particles that together represent irregular and ever-changing objects such as smoke, clouds, waterfalls, and explosions. A particle system can be a powerful tool for modeling a deformable object's motion and change of form since it has dynamic properties with time. As an object becomes more complicated and shows more chaotic behavior, however, we need much more parameters for describing its characteristics completely. Consequently, the conventional particle system leads to difficulty in managing all of the parameters properly since one parameter can affect the others. Moreover, motion equations for representing particles' behavior are usually approximated to gain speed-ups. The inevitable errors in calculating the equations can cause an unexpected outcome. In this paper, we present a new approach of applying fuzzy contol to mage particles' motion and attributes changes over time. We also give an implementation result of a fuzzy particle system to show the feasibility of the proposed method. Applications of the system to explosions, nebulae, volcanos, and grass are presented.

• Journal of the Korea Computer Graphics Society
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• v.14 no.4
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• pp.27-33
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• 2008

Physics-based graphic techniques are used when simulating and rendering natural phenomena such as smoke, water and flame with computational physics. We propose novel methods which render simulated particle data fast onto 3D using tetrahedron splat. We calculate the position and the normal vector of splat by SPH(smoothed particle hydrodynamics) method then we reconstruct splat into quadrangular pyramid to reduce seam. We implement this technique for SPH fluid simulation, and animate natural flow of water successfully.