한국게임학회 논문지 (Journal of Korea Game Society)

  • 제20권3호
  • /
  • Pages.65-74
  • /
  • 2020
  • /
  • 1598-4540(pISSN)
  • /
  • 2287-8211(eISSN)
한국게임학회 (Korea Game Society)
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적분기반 필터링을 이용한 소프트 섀도우

Soft Shadow with integral Filtering

  • 장파 (숭실대학교 미디어학부) ;
  • 오경수 (숭실대학교 미디어학부)
  • 투고 : 2020.05.18
  • 심사 : 2020.06.05
  • 발행 : 2020.06.20
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초록

섀도우 매핑 알고리즘에서 섀도우 맵이 확대되면 계단형 섀도우 실루엣이 나타난다. 본 논문에서는 재구성된 실루엣을 이용하여 소프트 섀도우를 생성한다. 먼저 섀도우 실루엣은 선형 또는 2차 곡선 모델을 기반으로 한 서브 텍셀 엣지 검출 방법을 통해 확보한다. 그리고 적분을 이용하여 정확한 섀도우 밝기의 평균을 얻기 위해 적분 기반 섀도우 필터링 알고리즘을 사용한다. 본 논문은 상기 과정을 통해 앨리어싱 현상이 두드러지는 실루엣을 효과적으로 제거하며 소프트 섀도우를 효율적으로 생성하는 방법을 제시한다.

In the shadow map method, if the shadow map is magnified, the shadow has a jagged silhouette. Herein, we propose a soft shadow method that filters reshaped silhouettes analytically. First, the shadow silhouette is reshaped through sub-texel edge detection, which is based on linear or quadratic curve models. Second, an integral shadow filtering algorithm is used to accurately obtain the average shadow intensity from a definite integral estimation. The implementation demonstrates that our solution can effectively eliminate jagged aliasing and efficiently generate soft shadows.

키워드

참고문헌

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