06 Note Phase

In this chapter, we will implement the tap phase and connect it to the tutorial update callback.

Timeline

The tap phase follows this timeline:

Phase elapsed time	Behavior
0 to 1 second	Intro
1 to 3 seconds	Fall
3 to 7 seconds	Frozen
Crossing 7 seconds	Hit
7 to 8 seconds	Pause
First frame at or after 8 seconds	Restart

The template already provides the phase clock in guide/tutorial/navigate.py. You do not need to edit this file.

PhaseTime holds the phase clock at the current and previous frames. Its methods and range properties mean:

Expression	Meaning
`phase_time.first(duration)`	The first range, from `0` up to `duration`
`intro.next(duration)`	A new range that starts where `intro` ends
`if intro`	The phase clock is in `intro`, including its start but excluding its end
`intro.elapsed`	Seconds since `intro` started
`intro.end`	The boundary at the end of `intro`
`pause.is_done`	The phase clock has reached or passed the end of `pause`
`phase_time.crossed(timing)`	The phase clock crossed the boundary since the previous frame

Calling first or next describes a range. It does not advance the clock. The crossed check compares two frames, so a one-time event still runs if one long frame skips past its exact boundary.

Tap Phase

In guide/tutorial/note.py, add the PhaseTime import shown below with the other guide imports. Then add tap_phase after play_note_hit_effects:

python

from guide.tutorial.navigate import PhaseTime


def tap_phase(phase_time: PhaseTime) -> bool:
    intro = phase_time.first(INTRO_DURATION)
    fall = intro.next(FALL_DURATION)
    frozen = fall.next(FROZEN_DURATION)
    hit_time = frozen.end
    pause = frozen.next(PAUSE_DURATION)

    if intro:
        draw_intro(intro.elapsed)
    if fall:
        draw_fall(fall.elapsed)
    if frozen:
        draw_frozen(frozen.elapsed)
    if phase_time.crossed(hit_time):
        play_note_hit_effects()

    return pause.is_done

The drawing ranges do not overlap, so at most one drawing check succeeds. The hit is a boundary rather than a range: it runs once when the clock crosses 7 seconds. The pause draws nothing, and pause.is_done becomes true when the full eight-second phase has finished.

Updating

The remaining project helpers control the clock around each update:

Helper	Use
`current_phase_time()`	Read the phase clock for the current and previous frames
`reset_phase()`	Start the phase clock over at zero
`finish_frame()`	Record this frame's time for the next `crossed()` check

Keep finish_frame() at the end of update.

Replace guide/tutorial/update.py with the following code. It draws the stage, runs the tap phase, and restarts the phase when tap_phase returns True:

python

from guide.tutorial.navigate import current_phase_time, finish_frame, reset_phase
from guide.tutorial.note import tap_phase
from guide.tutorial.stage import draw_stage


def update():
    draw_stage()
    if tap_phase(current_phase_time()):
        reset_phase()
    finish_frame()

The tutorial now loops through the intro, fall, frozen note, and one-second blank pause. The hit boundary has no visible or audible effect yet.

06 Note Phase ​

Timeline ​

Tap Phase ​

Updating ​

06 Note Phase

Timeline

Tap Phase

Updating