Weird circle issuses

During the process of designing the HUD for the game we discovered an interesting optical illusion. Our first version of the scope reticule was made of a cross with three circles. The circles were placed to help the player to be able to judge distance of objects that did not line up with the mil dot cross. When we placed this into the game and looked at the world we discovered that our circles did not look like circles. This is a similar illusion to Hering Illusion where lines appear to bend when lines cross them. The following image illustrates what we saw and if you look in the areas between the crosses you can see where the lines seem to bend.

First Version

After discovering this we had to sit down and redesign how we could give the player the same capability without having any optical illusions. In the process we also discovered that circles were displaying the wrong information with circles. This lead to the new design with corner lines showing the mil dots in 4 unit increments. This broke up with circles and let the player properly measure mil dots in the reigns away from the cross. The following image illustrates how we fixed the optical illusion with using square corner pieces.

Current Version