This fixes a regression that desyncs my Nova TAS after re-removing the
1-frame input delay.
Quick stopping is simply holding left/right but for less than 5 frames.
Viridian doesn't decelerate when you let go and they immediately stop in
place. (The code calls this tapping, but "quick stopping" is a better
name because you can immediately counter-strafe to stop yourself from
decelrating in the first place, and that works because of this same
code.)
So, the sequence of events in 2.2 and previous looks like this:
- gameinput()
- If quick stopping, set vx to 0
- gamerender()
- Change drawframe depending on vx
- gamelogic()
- Use drawframe for collision (whyyyyyyyyyyyyyyyyyyyyyyyyyyy)
And now (ignoring the intermediate period where the whole loop order was
wrong), the sequence of events in 2.3 looks like this:
- gamerenderfixed()
- Change drawframe depending on vx
- gamerender()
- gameinput()
- If quick stopping, set vx to 0
- gamelogic()
- Use drawframe for collision (my mind has become numb to pain)
So, this means that all the player movement stuff is completely the
same. Except their drawframe is going to be different.
Unfortunately, I had overlooked that gameinput() sets vx and that
animateentities() (in gamerenderfixed()) checks vx. Although, to be
fair, it's a pretty dumb decision to make collision detection be based
on the actual sprites' pixels themselves, instead of a hitbox, in the
first place, so you'd expect THAT to be the end of the dumb parade. Or
maybe you shouldn't, I don't know.
So, what's the solution?
What I've done here is added duplicates of framedelay, drawframe, and
walkingframe, for collision use only. They get updated in gamelogic(),
after gameinput(), which is after when vx could be set to 0.
I've kept the original framedelay, drawframe, and walkingframe around,
to keep the same visuals as closely as possible.
However, due to the removal of the input delay, whenever you quick stop,
your sprite will be wrong for just 1 frame - because when you let go of
the direction key, the game will set your vx to 0 and the logical
drawframe will update to reflect that, but the previous frame cannot
know in advance that you'll release the key on the next frame, and so
the visual drawframe will assume that you keep holding the key.
Whereas in 2.2 and below, when you release a direction key, the player's
position will only update to reflect that on the next frame, but the
current frame can immediately recognize that and update the drawframe
now, instead of retconning it later.
Basically the visual drawframe assumes that you keep holding the key,
and if you don't, then it takes on the value of the collision drawframe
anyway, so it's okay. And it's only visual, anyway - the collision
drawframe of the next frame (when you release the key) will be the same
as the drawframe of the frame you release the key in 2.2 and below.
But I really don't care to try and fix this for if you re-enable the
input delay because it's minor and it'd be more complicated.
2.2 Update (SDL2/PhysicsFS/Steamworks port) by Ethan Lee
Beta Testing by Sam Kaplan and Pauli Kohberger
Ending Picture by Pauli Kohberger
Versions
There are two versions of the VVVVVV source code available - the desktop version (based on the C++ port, and currently live on Steam), and the mobile version (based on a fork of the original flash source code, and currently live on iOS and Android).
Misa
3ca7b09012