From cc633b8fdff15d4b0e062402d04c664191213c35 Mon Sep 17 00:00:00 2001 From: Ed Mackey Date: Wed, 19 Jun 2024 14:51:35 -0400 Subject: [PATCH] Clarify and simplify formula for attenuation. (#2414) --- extensions/2.0/Khronos/KHR_materials_volume/README.md | 10 +++++++--- 1 file changed, 7 insertions(+), 3 deletions(-) diff --git a/extensions/2.0/Khronos/KHR_materials_volume/README.md b/extensions/2.0/Khronos/KHR_materials_volume/README.md index 168cf70d25..e31ebdb96a 100644 --- a/extensions/2.0/Khronos/KHR_materials_volume/README.md +++ b/extensions/2.0/Khronos/KHR_materials_volume/README.md @@ -157,11 +157,15 @@ T(*x*) = et*x* where T is commonly referred to as *transmittance*. -Substituting σt in the previous equation by its definition via *attenuation color* and *attenuation distance*, as defined above, and setting *x* = *d* we get +Substituting σt in the previous equation by its definition via *attenuation color* and *attenuation distance*, as defined above, we get -T(da) = e(log(*c*) / *d*) * *d* = *c* +T(x) = e(log(*c*) / *d*) * *x* -So, after traveling distance *d* through the medium we get attenuation color *c*. +The above formula can be simplified as: + +T(x) = *c* *x* / *d* + +So, after traveling distance *x* through a medium with attenuation color *c* and attenuation distance *d*, we get we get transmittance T(x). ## Base Color and Absorption