Task 2E: Add a Fresnel Term
Solution
In the fragment shader:
float fresnel = saturate(R0 + (1 - R0) * pow(1 - dot(directionToEye, normal), 5));
And a bit further down the fragment shader:
outColor.a = tex.a + fresnel;
Figure 9: Visualization of the fresnel value.
Figure 10: Environment mapping using fresnel term approximation.