Links collection of analytical AO techniques

Disc based AO

• Disc : "Dynamic Ambient Occlusion and Indirect Lighting" GPU Gems2
  • http://http.developer.nvidia.com/GPUGems2/gpugems2_chapter14.html
  • Used in NVidia Timbury demo http://www.nvidia.com/object/nzone_timbury_home.html

• Disc : "High-Quality Ambient Occlusion" GPU Gems 3
  • http://http.developer.nvidia.com/GPUGems3/gpugems3_ch12.html

• Disc ? (Object Based Analytical Ambient Occlusion) : "Agni's Philosophy" SQEXOC 2012
  • http://www.4gamer.net/games/032/G003263/20121201006/
  • Similar method to "Dynamic Ambient Occlusion and Indirect Lighting" GPU Gems2

Sphere, Ellipsoids based AO

• Sphere : "sphere ambient occlussion" by iq
  • http://www.iquilezles.org/www/articles/sphereao/sphereao.htm

• Sphere, Cuboid : "Deferred Occlusion from Analytic Surfaces" ShaderX 7
  • http://www.shaderx7.com/TOC.html
  • メモ0 : 球が平面に埋まり始めた時に, 球と平面間の高さに応じて線形補間で暗くする方法が載っています.
  • メモ1 : フル解像度で 1 成分の加算ブレンドを使う代わりに, 1/2 * 1/2 解像度で RGBA の加算ブレンドを使ってブレンドを並列化する方法もあります (ベクトル化).

• Ellipsoids : "Rendering with Conviction" GDC2010
  • http://www.selfshadow.com/talks/rwc_gdc2010_v1.pdf

• Sphere, Ellipsoid : "Lighting Technology of The Last of Us". SIGGRAPH 2013
  • http://miciwan.com/SIGGRAPH2013/Lighting%20Technology%20of%20The%20Last%20Of%20Us.pdf

• Capsule? (Actually Ellipsoid?) : "Crafting a Next-Gen Material Pipeline for The Order : 1886" GDC2014
  • http://t.co/17GYfuVOze
  • http://www.readyatdawn.com/presentations/
  • https://readyatdawn.sharefile.com/share#/view/s3187a0527304cf1b/fi2a51de-11e1-cfde-5bb1-3172f5951f21
  • メモ : スライドにはカプセル AO と書いてあるけど, ノートを読むと内容的には楕円体 AO みたいです.

• Box/Ellipsoid (Radial Ambient Occlusion): "Lighting and Simplifying Saints Row: The Third" GDC2012
  • http://twvideo01.ubm-us.net/o1/vault/gdc2012/slides/Programming%20Track/Kircher_Lighting_and_Simplifying_Saints_Row_The_Third.pdf

• Ellipsoid : "Hardware Accelerated Ambient Occlusion Techniques on GPUs" I3D 2007
  • http://www.okanarikan.com/static/images/Papers/SSAO/paper.pdf

• Ellipsoid
  • "Fast Tree Ambient Occlusion Approximation"
    • http://www.researchgate.net/profile/Marc_Jaeger/publication/220585645_A_Fast_Ambient_Occlusion_Method_for_Real-Time_Plant_Rendering/links/0fcfd506d41db37d73000000.pdf
  • "A Fast Ambient Occlusion Method for Real-Time Plant Rendering"
    • http://www.researchgate.net/profile/Marc_Jaeger/publication/220585645_A_Fast_Ambient_Occlusion_Method_for_Real-Time_Plant_Rendering/links/0fcfd506d41db37d73000000.pdf

ShaderToy demos

• Sphere AO
  • https://www.shadertoy.com/view/4djSDy

• Box AO
  • https://www.shadertoy.com/view/4djXDy

• Box AO with Clamping
  • https://www.shadertoy.com/view/4sSXDV

• Triangle AO
  • https://www.shadertoy.com/view/XdjSDy

Analytical shadow

• "Fast Rounded Rectangle Shadows" (2d)
  • http://madebyevan.com/shaders/fast-rounded-rectangle-shadows/
• "Fast Shadows on Rectangles" Michael Herf 2001
  • http://stereopsis.com/shadowrect/

Related

• "sphere projection"
  • http://www.iquilezles.org/www/articles/sphereproj/sphereproj.htm
• "working with ellipses"
  • http://www.iquilezles.org/www/articles/ellipses/ellipses.htm
• "sphere visibility"
  • http://www.iquilezles.org/www/articles/sphereocc/sphereocc.htm