Someone explain the technical reason for why Double Jump Cancelling exists.

[LovinMitts]

I would've titled this ELI5, but I want the full details as to why double jump cancelling occurs. If you feel like, someone can also explain how PM knows when to DJC and to do a Rising Aerial.

 

[Yeroc]

For normal characters when you jump, the game applies a one-time vertical momentum boost. Melee DJC characters do not have that, instead they have a dj animation that has animated translation, effectively distributing that momentum in little tiny amounts across all the frames of the dj. When you do an aerial, you leave the dj action, so the little momentum bumps stop being added, and you just fall out of the air where you were.

In Brawl, it didn't work that way. DJC characters have coding that remembers that they were double jumping and continues to apply the momentum. What the PMDT did was add a check near the start of the aerial attack actions that check for if the jump button had been released. If so, it reset all vertical momentum, killing off the Brawl dj and mimicing the Melee DJC. If you were still holding the button, it allowed the brawl dj to continue as normal.

 

[-ACE-]

It certainly helps, ness/yoshi/peach's double jumps would be a huge commitment without this extra mechanic.