The Ray Casting Kajam has begun! 3 4

That's right! From the 4th to the 31st of January, we're having another Kajam event. Your mission is to make a game that uses ray casting in some way, graphical or otherwise.

But what is ray casting?

In 3D graphics, ray tracing is a rendering method in which "virtual light rays are "cast" or "traced" on their path from the focal point of a camera through each pixel in the camera sensor to determine what is visible along the ray" (Wikipedia article). For a resolution of 320x240, that would be 76800 rays each frame! Ray casting is an optimised version of Ray tracing where only one ray is required for each column of pixels, which means only 320 rays each frame! This is the technique used in classic games like Wolfenstein 3D!

So I have to write an esoteric retro 3D renderer?

I encourage you to give it a go, but it's not required! There are plenty of other reasons why you might "cast rays" in a game. The same ideas are often used in physics simulations, AI, and sometimes seemingly simple operations, like checking if a player can jump. So please feel free to use your imagination! If it involves rays, we're happy :).

But what is a Kajam?

Kajam competitions are month-long events in which people make a small video game focusing on a specific aspect of game development. They're a perfect opportunity to learn, experiment and level-up your gamedev skills!

Detailed rules here.

Some relevant links:

• Retro FPS ray casting tutorial at lodev.org
• Ray-Casting Tutorial For Game Development And Other Purposes by F. Permadi
• A ray casting renderer in 265 lines of JavaScript
• Different uses of ray casting in Unity (interesting even for non-Unity devs)
• AI ray casting in general