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# File Documents/Illumination.xml

`             objects have had a color that is entirely part of the mesh data, pulled from a`
`             uniform variable, or computed in an arbitrary way. This makes all of our objects`
`             look very flat and unrealistic.</para>`
`-        <para>Properly modeling the interaction between light and a surface is vital in creating`
`-            a convincing world. Lighting defines how we see and understand shapes to a large`
`-            degree. This is the reason why the objects we have used thus far look fairly flat. A`
`-            curved surface appears curved to us because of how the light plays over the surface.`
`-            The same goes for a flat surface. Without this visual hinting, surfaces appear flat`
`-            even when they are modeled with many triangles and yield a seemingly-curved`
`-            polygonal mesh.</para>`
`-        <para>A proper lighting model makes objects appear real. A poor or inconsistent lighting`
`-            model shows the virtual world to be the forgery that it is. The tutorials in this`
`-            section will introduce some light/surface models and explain how to implement`
`-            them.</para>`
`+        <para>Properly modeling the interaction between light and a surface is vital in creating a`
`+            convincing world. Lighting defines how we see and understand shapes to a large degree.`
`+            The lack of lighting is the reason why the objects we have used thus far look fairly`
`+            flat. A curved surface appears curved to us because of how the light plays over the`
`+            surface. The same goes for a flat surface.</para>`
`+        <para>Without this visual hinting, surfaces appear flat even when they are modeled with many`
`+            triangles and yield a seemingly-curved polygonal mesh. A proper lighting model makes`
`+            objects appear real. A poor or inconsistent lighting model shows the virtual world to be`
`+            the forgery that it is.</para>`
`+        <para>This section of the book will cover lighting, using a variety of light/surface`
`+            modelling techniques. It will cover dynamic range and linear colorspaces in lighting`
`+            equations. Also, it will cover techniques to use lighting to produce entirely fake`
`+            surfaces.</para>`
`     </partintro>`
`     <xi:include href="Illumination/tutorial 09.xml"/>`
`     <xi:include href="Illumination/tutorial 10.xml"/>`