How Do Wall Kicks Work In Tetris Friends?
I am trying to program a Tetris clone based very closely off of Tetris Friends 2 Player Battle mode.
Is anyone very familiar with how wall kicks work in this game? Or know where to find reference material on the subject?
I have read up on SRS and DTET, but unless I am mistaken neither of them perfectly describes how wall kicks work in Tetris Friends (rotation matches SRS identically when not considering wall kicks).
One particular behavior that has been confusing me is how Tetris Friends handles situations where either a kick upwards or to the side might be appropriate. Tetris Friends behaves like this with the line piece in this case:
Before After
........ ........
........ ..X.....
..XXXX.. ..X.....
....0... ---> ..X.0...
...00... ..X00...
...00... ...00...
When I would have expected one of the following:
Kick Left Kick Right
...X.... .....X..
...X.... .....X..
...X.... .....X..
...X0... ---> ....0X..
...00... ...00...
...00... ...00...
Can anyone explain this behavior? Even if Tetris Friends has a strange and unique wall kick system, I'd still like to match it as closely as I can. Is anyone familiar with it?
Best Answer
With SRS, all pieces follow the same kick table except for the I-piece.
What you describe happening is exactly how SRS is supposed to work. In either case, rotating left or right will have the same effect here. Going from the original state (state North) and rotating right will first try no kicks. The piece overlaps and tries the next kick offset, -2, 0, which shifts the piece left two columns.
If you try to rotate left, the natural rotation is tried, fails, and the next kick, -1, 0, is tried and works, the piece moves left once. Because the natural left rotation moves the piece left already, it ends up in the same position as a right rotation.
This while not important to your question does bring up a left bias in the I-piece rotation, that isn't seen with the other pieces.
The reason these rotations were chosen is kind of a side effect of how SRS works. With SRS, all rotations are reversible. This means when you rotate and a piece kicks, you can always rotate the other direction to get yourself out. These kicks are just meant for the piece to be able to rotate off of a wall, but the side effect is the reverse (what your example is) has a weird behavior.
Pictures about "How Do Wall Kicks Work In Tetris Friends?"
How do you wall kick in Tetris?
Wall Kick (\u58c1\u8e74\u308a, Kabe Geri), also known as "Triangle Kick" (\u4e09\u89d2\u8e74\u308a, Sankaku Geri), Wall Climb and Wall Jump, is an ability that allows the player's character to reach higher places that usually can't be reached with a normal jump, to move down slower and safely see what is below, or quickly climb to escape a danger.What is a wall kick?
The Super Rotation System, also known as SRS and Standard Rotation System is the current Tetris Guideline standard for how tetrominoes behave, defining where and how the tetrominoes spawn, how they rotate, and what wall kicks they may perform.What is SRS in Tetris?
The Super Rotation System, or SRS is the current Tetris Guideline standard for how tetrominoes rotate and what wall kicks they may perform. SRS traces its roots back to 1991 when BPS introduced third and fourth rotation states for the S, Z, and I tetrominoes in the game Tetris 2 + Bombliss.Sources: Stack Exchange - This article follows the attribution requirements of Stack Exchange and is licensed under CC BY-SA 3.0.
Images: Clem Onojeghuo, Ksenia Chernaya, Ksenia Chernaya, EKATERINA BOLOVTSOVA