         return vec3(texture(material.tex.ks, texCoord));
     }
 
-    return material.ks.xyz;
+    return material.ks.xyz / Pi; // Phong specular to blinn-phong exponent
 }
 
 float getNs(Material material, vec2 texCoord)

        ns = texture(material.tex.ns, texCoord).r;
    }

    return max(ns, 0.001);
}

vec3 getNormal(Material material, vec2 texCoord, vec3 N, vec3 T, vec3 B)

#ifndef BLINNPHONGMATERIAL_GLSL
#define BLINNPHONGMATERIAL_GLSL
// Blinn-Phong specular and exponent :
// As this shader is built on Blinn-Phong NDF, that approximate Cook-Torrance,
// Specular parameters from the asset must be converted so that specular highlight look the same than with
// standard Phong BRDF (divided both Ks and Ns by Pi looks good).
// See http://www.thetenthplanet.de/archives/255 for intuitions
const float Pi = 3.141592653589793;

struct BlinnPhongTextures
