fennel-ray-casting/reference/notes.md

Notes

Reminders

• wrap.fnl is the "entrypoint" for the project.
• Run the project via make or love (ex: love . from base directory)

Ray-Casting Basics

Every frame, from left to right, a vertical slice is drawn. The slice can be a part of a texture, or a color. Generally, the slice is drawn the full height of the wall; half-walls are possible, and presumably so are windows. The slice to be drawn is determined by sending a ray from the camera (or camera plane) in the facing direction, until the ray intercepts with a wall. The walls, as well as most other level details, are provided in a 2-d array, generally of numbers. In this example, the number 0 represents open space, and every number above 0 represents a wall with a specific texture. The initial way of determining the ray is using Euclidean geometry, but this can result in a fish-eye lens appearance. Lode's tutorial uses vectors to establish a camera plane from which all calculations are performed. This helps reduce the fish-eye appearance.