[Bf-blender-cvs] [c4201e57f36] blender2.8: Eevee: Re: Fix NaN

[Clément Foucault]

Commit: c4201e57f36e7a5bcb711bd1a92d5b334cd40dff
Author: Clément Foucault
Date:   Fri Aug 11 01:25:40 2017 +0200
Branches: blender2.8
https://developer.blender.org/rBc4201e57f36e7a5bcb711bd1a92d5b334cd40dff

Eevee: Re: Fix NaN

This should be faster and apparently more stable.

===================================================================

M	source/blender/draw/engines/eevee/shaders/bsdf_common_lib.glsl

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diff --git a/source/blender/draw/engines/eevee/shaders/bsdf_common_lib.glsl b/source/blender/draw/engines/eevee/shaders/bsdf_common_lib.glsl
index 520318d3134..4d2f92c6955 100644
--- a/source/blender/draw/engines/eevee/shaders/bsdf_common_lib.glsl
+++ b/source/blender/draw/engines/eevee/shaders/bsdf_common_lib.glsl
@@ -415,7 +415,9 @@ float F_eta(float eta, float cos_theta)
 /* Fresnel */
 vec3 F_schlick(vec3 f0, float cos_theta)
 {
-	float fac = pow(1.0 - cos_theta, 5);
+	float fac = 1.0 - cos_theta;
+	float fac2 = fac * fac;
+	fac = fac2 * fac2 * fac;
 
 	/* Unreal specular matching : if specular color is below 2% intensity,
 	 * (using green channel for intensity) treat as shadowning */