1 files changed, 15 insertions, 0 deletions
diff --git a/res/effectlib/defaultMaterialFresnel.glsllib b/res/effectlib/defaultMaterialFresnel.glsllib
new file mode 100644
index 0000000..0d474bc
--- /dev/null
+++ b/res/effectlib/defaultMaterialFresnel.glsllib
@@ -0,0 +1,15 @@
+#ifndef DEFAULT_MATERIAL_FRESNEL_GLSLLIB
+#define DEFAULT_MATERIAL_FRESNEL_GLSLLIB
+
+float defaultMaterialSimpleFresnel( in vec3 N, in vec3 viewDir, in float ior, float fresnelPower )
+{
+    float F = ((1.0-ior) * (1.0-ior)) / ((1.0+ior) * (1.0+ior));
+    float VdotN = dot(viewDir, N);
+    float dvn = abs( dFdx(VdotN) * dFdy(VdotN) );
+    VdotN = clamp( VdotN, 0.0, 1.0 );
+    float ratio = F + (1.0 - F) * pow(1.0 - VdotN, fresnelPower);
+
+    return clamp( ratio * pow( VdotN, dvn * fresnelPower ), 0.0, 1.0 );
+}
+
+#endif