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README.md

@@ -63,7 +63,7 @@ It is first important to choose a microfacet model to describe how light interac
 
 ### Environment Maps
 
-This is where environment maps come in! Environment maps can be thought of as a light source that surrounds the entire scene (usually as an encompassing cube or sphere) and contributes to the lighting based on the color and brightness across the entire image. As you might guess, it is extremely inefficient to assess the light contribution to a single point on a surface from every visible point on the environment map. In offline applications, we would typically resort to using importance sampling within the render and just choose a predefined number of samples. However, as described in [Unreal Engine's course notes on real-time PBR](http://blog.selfshadow.com/publications/s2013-shading-course/karis/s2013_pbs_epic_notes_v2.pdf), we can reduce this to a single texture lookup by baking the diffuse and specular irradiance contributions of the environment map into textures. You could do this youself as described in the course notes, but there is also a resource called [IBL Baker](http://www.derkreature.com/iblbaker/) that will create these textures for you. The diffuse irradiance can be stored in a cube map, however, we expect the sharpness of specular reflection to diminish as the roughness of the object increases. Because of this, the different amounts of specular irradiance can be stored in the mip levels of the specular cube map and accessed in the fragment shader based on roughness.
+This is where environment maps come in! Environment maps can be thought of as a light source that surrounds the entire scene (usually as an encompassing cube or sphere) and contributes to the lighting based on the color and brightness across the entire image. As you might guess, it is extremely inefficient to assess the light contribution to a single point on a surface from every visible point on the environment map. In offline applications, we would typically resort to using importance sampling within the render and just choose a predefined number of samples. However, as described in [Unreal Engine's course notes on real-time PBR](http://blog.selfshadow.com/publications/s2013-shading-course/karis/s2013_pbs_epic_notes_v2.pdf), we can reduce this to a single texture lookup by baking the diffuse and specular irradiance contributions of the environment map into textures. You could do this yourself as described in the course notes, but there is also a resource called [IBL Baker](http://www.derkreature.com/iblbaker/) that will create these textures for you. The diffuse irradiance can be stored in a cube map, however, we expect the sharpness of specular reflection to diminish as the roughness of the object increases. Because of this, the different amounts of specular irradiance can be stored in the mip levels of the specular cube map and accessed in the fragment shader based on roughness.
 
 **Diffuse Front Face**
 
@@ -75,7 +75,7 @@ This is where environment maps come in! Environment maps can be thought of as a
 
 ### BRDF
 
-At this point, we are able to pick out the diffuse and specular incoming light from our environment map, but we still need to evaluate the BRDF at this point. Instead of doing this computation explicitly, we use a BRDF lookup table to find the BRDF value based on roughness and the viewing angle. It is important to note that this lookup table changes depending on which microfacet model we use! Since this project uses the Cook-Torrance model, we use the following texture in which the y-axis corresponds to the roughness and the x-axis corresponds to the dot product between the surface normal and viewing vector.
+At this point, we can pick out the diffuse and specular incoming light from our environment map, but we still need to evaluate the BRDF at this point. Instead of doing this computation explicitly, we use a BRDF lookup table to find the BRDF value based on roughness and the viewing angle. It is important to note that this lookup table changes depending on which microfacet model we use! Since this project uses the Cook-Torrance model, we use the following texture in which the y-axis corresponds to the roughness and the x-axis corresponds to the dot product between the surface normal and viewing vector.
 
 ![](textures/brdfLUT.png)
 
@@ -104,7 +104,7 @@ These functions may be swapped into pbr-frag.glsl to tune your desired rendering
 
 ### Surface Reflection Ratio (F)
 
-**Frensel Schlick**
+**Fresnel Schlick**
 Simplified implementation of fresnel from [An Inexpensive BRDF Model for Physically based Rendering](https://www.cs.virginia.edu/~jdl/bib/appearance/analytic%20models/schlick94b.pdf) by Christophe Schlick.
 
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