In the fourth installment of the ships mod technology demo, I show off the new collision system. Since Minecraft can't natively handle complex interactions between entities, a new system was needed. Watch the video to see the collision system in action.

Originally, ship collision was based off of Minecraft's built-in entity collision system. Each ship was modeled as a large number of entities shaped like blocks. This worked for small ships, when the largest distance between any pair of blocks was small, but larger ships exposed problems with this collision system. Players would fall right through the floor of larger ships. There wasn't really a way to fix the built-in collision system to avoid these problems, so I had to create something entirely new.

What you see in the video is a debug render of the new collision system. The player is modeled as the green box and ship blocks are highlighted in red when they impede the player's movement. Later, the video shows how dynamically-changing blocks (like doors) are handled seamlessly.

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