To achieve projection in the 18th puzzle, create a render texture with a camera that captures a different scenery, and set it as a material on the interior wall. There are four walls, front, back, left, and right, and we want to project a 360-degree view around them. For this reason, we prepared four cameras for rendering textures, each of which took a 90-degree view.
We thought that by rotating and moving the render texture cameras, we would be able to experience an interesting image inside the projected room. At first, we constructed a scene in which the characters moved through a dungeon-like maze, but as the camera approached pillars and other objects, the projected image became unnatural, so we gave up on the maze.
We are currently considering using a gimmick that rotates the camera inside a circular garden-like structure.
There are two things that need to be considered with this concept.
The first is whether the camera projection method should be perspective projection or parallel projection. Second consideration is whether the wall to be projected onto is a flat or curved surface.
Either method has advantages and disadvantages in terms of distortion and shooting range, and we want to decide based on consistency with the puzzle and sense of realism.