Portal Cards

FraserJamesH
May 7, 2020
1 min read

I've been working a lot on filling out the landscape more and decided that some caves could be a nice touch to add. I did the initial block in of the cave but soon found that the entrance seemed too bright and needed some form of fog. In the game I'm using linear fog but this is only used to fade objects in the distance and wouldn't work in this case. Instead I remembered a technique that they used heavily in the game ABZÛ which was what they called portal Cards. The effect is achieved through a shader that fades when the camera gets close to the object the shader is on, this is done using the scene depth. I decided to replicate the effect in Unity's shader graph and as I already I had a depth fade sub graph that I had made for the water it was particularly easy. You can see bellow the effect it has and how small the graph actually is to achieve this effect. The first part gets the scene depth and fades the objects alpha when the camera is near, the second part is the depth fade that fades the edges of the plane depending on what the objects is intersecting with.

An important note to mention is setting the render queue to 3001 as this makes sure that there isn't any issues with other transparent materials being rendered in-front of the material breaking the effect.