Edge Blend and Reflections

Edge Blend and Reflections

Figure One shows a texture mapped ball being reflected in a mirror at 45 degrees to the camera angle (see right). This allows us to see the back of the ball in the reflection, and indeed that is what we see - the seam at the back of the ball where the left and right edges of the picture meet is clearly visible. The majority of shader nodes work like this - the results of the node are calculated, and that result is reflected back at us.

Fig 1: Normal Reflections

Edge blend works differently. As figure 2 shows, it is not the result of the original edge blend calculation that is shown in the reflection, but a new edge blend, calculated as if the object in the mirror was physically present, and not simply a reflection.

Fig 2: Edge Blend Reflected

Figure three shows why this is the best way to show edge blends in reflections. It shows the Poser 2 casual man with toon outlines calculated from the edge blend, as seen in our main tutorial. The reflection of our figure shows the side view, and because the edge blend is calculated again the outlines show correctly. If the reflection showed the results of the original edge blend, our toon man would have a black line along the side of his arm in the reflection.

Fig 3: Edge blend toon edged reflected