Short Charge
Short charging is the manipulation of the way the Speed Booster functions to attain blue suit in a shorter distance than normal, or compared to quick charging.
Contents
Speed Boost Counter
The speed boost counter will increment if dash is held while Samus's legs are in the following position (typically referred to as the "magic frame"):
When the counter reaches "4", you will attain blue suit.
The speed boost counter is separate from momentum. For every frame you are on the ground while holding dash and a direction, your momentum will increase. The goal of short charging is to increment the counter to 4 while having Samus gather less momentum: traveling a shorter distance than usual. This can be accomplished either via "Tapping", or "Stutter Step + Tapping".
Tapping
Tap dash only when the magic frame is happening (see Timing). If executed correctly, your speed counter will increase at the usual speed, but your momentum will increase much slower because it is only increasing while you are holding dash.
To be explicit, the sequence for humans should be:
- Press dash
- As short of a time you are comfortable with
- Magic frame happens
- As short of a time you are comfortable with
- Release dash
You can, in places with enough room, tap dash for the first few magic frames, and then tap and hold dash for the remaining ones. Quick charging is the easiest version of this idea: just one tap and hold.
When tapping, you can hold the taps for a smidge longer to make sure that you hit the magic frame.
Longer taps and/or fewer taps make the short charge easier. More taps and/or shorter taps cause Samus to more forward less, letting her charge shinespark in smaller spaces. They also increases the difficulty of the short charge, so you only need to do them when you don't have room for an easier one.
Stutter Step
This is a second way to reduce the distance Samus travels, in addition to tapping. Before the magic frame, you can release forward for a brief moment to reduce Samus' speed without interrupting her running animation.
For a human, that looks like this:
- Hold forward
- Release forward for as short a time as you physically can
- Hold forward
- Magic frame happens
Releasing forward for too long will restart Samus' running animation and set the speed boost counter to 0. This also happens if you release forward too early, before she's built up enough momentum. Try to release at or after halfway to the magic frame.
Usually a human will do just one stutter step, before the first magic frame. One stutter greatly reduces the distance traveled, and the player is free to focus on tapping for the rest of the short charge.
Notation
Sometimes players talk to each other about what kind of short charge they're doing in a particular room.
If you tap dash for the first two magic frames and then tap and hold for the 3rd + 4th, that's known as a "3 tap". If you also stutter step at the beginning, that's called a "stutter 3 tap" or "stutter 3".
A "1 tap" is sometimes called quick charging.
Timing
Assuming the speed boost counter increments each time, the first 4 magic frames happen when this many 60ths of a second have passed since Samus started moving: 25, 50, 70, 85. In other words, the gap between taps starts at a bit less than half a second, then drops to 1/3rd of a second on the third magic frame and 1/4th of a second on the fourth.
The change in timing as the speed boost counter increments is part of why a 2 tap is significantly easier than a 3 tap (slight timing difference) or 4 tap (substantial timing difference). It's often easier to add a stutter than to add more taps. Since the time between the third and fourth magic frames is so short anyway, you also save very little space with a 4 tap compared to a 3 tap. But maybe a 4 tap isn't that tricky for you: use your judgement!
For musicians: short charge can be achieved using a tempo between 153-160bpm, by pressing forward at the start of the bar, and tapping dash on each successive beat. For example: 1. hold forward 2. tap dash 3. hold dash (2 tap) or 1. hold forward 2. tap dash 3. tap dash 4. hold dash (3 tap). Pressing down at the first beat of the next bar will charge a shinespark. See the tutorial by Truemoss for further details.
4 tap rhythm:
An example of a "stutter 3" short charge:
An example of a short charge being performed to swiftly obtain the Missile pack in Main Street:
Pixel Values
Here, some pixel values are provided for short charging on NTSC. These assume perfect taps. Values are given in pixel.subpixel, and it is the space from start to charging a spark. Slightly less space would work, as Samus "slides" into the wall as she crouches.
- No short charge: 501.08192 (about 31.3 tiles)
- 1-tap (quick charge): 351.00000 (about 21.9 tiles)
- 2-tap: 272.16384 (about 17 tiles)
- 3-tap: 236.40960 (about 14.8 tiles)
- 4-tap: 225.45056 (about 14.1 tiles)
Stuttering is a lot more complicated to discuss. For simplicity, only the best patterns with no dash button use are considered. The values here assume a perfect 4-tap afterwards.
To specify the pattern that gives this value, something like 9_14_ is stated. This means press forward for 9 frames, release for one frame, forward for 14 frames, release for one frame, and then the next frame is the first magic frame.
- Single stutter: 199.16384 (about 12.45 tiles) [Pattern: 11_13, or any longer initial walk up to 24_]
- Double stutter: 175.00000 (about 10.94 tiles) [Pattern: 9_14_]
- Triple stutter: 167.57344 (about 10.49 tiles) [Patterns: 5_7_10_, 6_7_9_]
- Quadruple stutter: 165.28672 (about 10.34 tiles) [Patterns: 3_4_5_9_, 3_5_4_9_, 4_4_4_9_]
- Quintuple stutter: 165.16384 (about 10.33 tiles) [Patterns: 3_4_4_3_6_, 3_4_3_3_7_, 3_3_3_4_7_, 2_3_4_4_7_]
Any higher-order stutter is less optimal, although may provide more consistent short charges so shouldn't be discarded.
Note these stutter patterns were found by exhaustive search. Conclusions about stuttering from this are:
- It is always best to release forward for the shortest amount of time possible (every additional frame of forward release adds another pixel);
- It is best for your last stutter to happen just before the magic frame (although this makes it harder to tap);
- Your initial walk should be shorter than following runs, except for a single stutter where it just needs to be long enough;
- Your last walk should be longer than previous ones, except for a single stutter again.
The last two pieces of advice are about optimal stutters: Usually, it is easier to evenly space stutters.
Finally, to complete distances, here are TAS patterns:
- Cpadolf's old TAS pattern: 164.12288 (about 10.262 tiles)
- sniq's new TAS pattern: 164.08192 (about 10.258 tiles)
- sniq's moonwalk TAS pattern: 162.28672 (about 10.152 tiles) [Note this requires being able to moonwalk backwards for a frame at the start, so might be misleading given how distance was measured.]
Tutorials
- Oatsngoats - Short Charge/Stuttering tutorial
- ShinyZeni Speedbooster/Short Charging Timestamp in the General Movement Tutorial
- Kojakt - A Stutter 3-Tap Explanation.
- Sweetnumb - Stutter short charge tutorial
- Dbx - Super Short Charge tutorial
- Charles_Black - Short Charging with stutters and without
- TrueMoss - Short Charge tutorial
