1. ShaderX4 4.2 Eliminating Surface Acne with Gradient Shadow Mapping ohyecloudy(http://ohyecloudy.com) shader study(http://cafe.naver.com/shader.cafe)

2. The Phenomenon of Surface Acne Depth Bias to the Rescue Depth Gradient Depth Comparison as a Fuzzy Function Conclusion

4. Light Sampled surface 깊이 맵에서 샘플링 된 깊이 값. Surface 렌더링하는 오브젝트 표면 False Shadow

5. The Phenomenon of Surface Acne Depth Bias to the Rescue Depth Gradient Depth Comparison as a Fuzzy Function Conclusion

6. Light Light Depth Bias 평면에선 문제가 없다.

7. false nonshadowing 지나친 depth bias로 그림자가 생겨야 할 곳에 안 생긴다. 곡면에선 적절한 Depth Bias가 Depth Gradient마다 다르다. 곡면에선 문제

9. The Phenomenon of Surface Acne Depth Bias to the Rescue Depth Gradient Depth Comparison as a Fuzzy Function Conclusion

10. Light depth map에서 이웃 샘플간 차이 입사각의 탄젠트와 비례한다. bias scale에 사용 가능. Depth Bias Depth Gradient

11. // gradient calculation float pixeloffset = INVPIXEL / 2; float4 depths = float4( tex2D( ShadowSampler, shadowP + float2( -pixeloffset, 0 ) ).x, tex2D( ShadowSampler, shadowP + float2( +pixeloffset, 0 ) ).x, tex2D( ShadowSampler, shadowP + float2( 0, -pixeloffset ) ).x, tex2D( ShadowSampler, shadowP + float2( 0, +pixeloffset ) ).x ); float2 differences = abs( depths.yw - depths.xz ); float gradient = min( GradientClamp, max( differences.x, differences.y ) ); difference

12. The Phenomenon of Surface Acne Depth Bias to the Rescue Depth Gradient Depth Comparison as a Fuzzy Function Conclusion

13. Fuzzy depth comparison unbiased depth comparison 1 uncertainty region

14. // visibility function float delta_z= centerdepth + gradient * ShadowGradientScaleBias- In.ShadowmapCoord.z; float visibility = saturate( 1 + delta_z / ( gradient * ShadowFuzzyWidth ) );

16. The Phenomenon of Surface Acne Depth Bias to the Rescue Depth Gradient Depth Comparison as a Fuzzy Function Conclusion

17. 왜 acne가 생기는지 알아봤다. surface acne를 없애기 위한 기술 depth bias gradient-scaled bias fuzzy function