Background Study
Problems
This week, I have been creating the background tiles for the game. I tried to created highly realistic and detailed tiles at the beginning because I thought it would suit the “horror” game aesthetics well. The tile looked good without putting into the game scene. However, when I loaded it into Unity and tested it, problems occurred. A screenshot of the testing scene is shown below. 
There were mainly two problems. One was that the floor tiles were way to sharp and detailed. They were distracting the players’ eyes from focusing on the main characters of the scene. The other problem was that it did not fit in the perspective. The camera height for the character was about their body height while the camera for the tiles was an orthographic camera from right above. Simply put, the floor tiles looked more like a wall in the game world rather than a floor where the characters stepped.
Methods
First, I added a shadow to one of the characters. I hope this could solve the problem and make players feel the characters are standing on the ground. It felt slightly better but differences weren’t obvious.
I then assumed that the tiles were too detailed with high contrast. I edited the tiles in photoshop and lowered the contrast. Here is what I got after that.
The improvement was quite obvious. The attention had been shifted to the characters. The brain focused more on the characters and analysed less on the background. With a very dark shadow, the illusion of the character standing on the ground is basically created. Seeing the improvement, I decided to push the experiment even further. Since a less detailed background suited better for the game scene, I removed all the details from the tiles. I had the game screenshot as below:
It turned out to be able to create the illusion much better than the previous two backgrounds. together with the shadow. It felt like the right hand side character was indeed standing on that floor, even if the camera angles for them were totally different.
Conclusions
To create the illusion of a 3D world using 2D characters and tile backgrounds in a 2D scene, the background must not be too sharp or detailed. A rather dull and unattractive background is actually more helpful to the illusion.
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