定制Novation Launchpad的Ableton Live MIDI脚本：多矩阵导航与轨道控制

Great question—let's walk through exactly how to build this custom Launchpad setup inspired by Will Marshall's APC MKii workflow. I've broken this down into actionable steps, including a code example to get you started:

First, let's align on the setup you want:

• Four independent 2×7 clip launch matrices (switchable via navigation)
• A dedicated bottom row for track stop buttons, with dynamic LED feedback:
  • Green when the track is playing, press to stop
  • Red when the track is stopped

First, map out how to split the Launchpad's 8×8 grid. Here's a practical breakdown (adjust based on your preferred layout):

• Clip Matrices: Four 2-row ×7-column zones. For example:
  • Matrix 1: Rows 0-1, Columns 0-6
  • Matrix 2: Rows 2-3, Columns 0-6
  • Matrix 3: Rows 4-5, Columns 0-6
  • Matrix 4: Rows 0-1, Columns 1-7 (shifted right for alternate track groups)
• Stop Row: Row 7 (bottom row), Columns 0-6 (one button per track in the active matrix)
• Navigation Button: Repurpose an unused grid button (e.g., Row7, Column7) to cycle between the four matrices.

The navigation system needs to do two things when triggered:

1. Clear the current matrix's LEDs to avoid overlap
2. Load and display the clip states for the newly selected matrix

• Track which matrix is active with a variable (e.g., current_matrix = 0), and increment it modulo 4 to cycle through all four.

This is the most user-critical part—here's how to handle the stop buttons:

• State Tracking: Keep a list to track whether each track is playing (True) or stopped (False)
• LED Feedback:
  • When a track plays, set its stop button to bright green ((0,63,0) in RGB for most Launchpads)
  • When stopped, set it to bright red ((63,0,0))
• Button Press Action: When a stop button is pressed, send a track stop command to your DAW, toggle the track's state, and update the LED color immediately.

Here's a working skeleton using the launchpad_py library (install via pip install launchpad-py). This handles grid input, LED updates, navigation, and stop row logic:

from launchpad_py import Launchpad
import time

# Connect to your Launchpad (adjust model name if needed)
lp = Launchpad()
if not lp.Open(0, "Launchpad Mk2"):
    print("Failed to connect to Launchpad")
    exit()

# Define our 4 clip matrices (adjust rows/cols to your layout)
matrices = [
    {"rows": [0, 1], "cols": list(range(7))},
    {"rows": [2, 3], "cols": list(range(7))},
    {"rows": [4, 5], "cols": list(range(7))},
    {"rows": [0, 1], "cols": list(range(1, 8))}
]
current_matrix = 0
# Track play/stop states for 7 tracks
track_states = [False] * 7

def update_stop_row():
    """Update the bottom row LEDs based on track states"""
    for col in range(7):
        color = (0, 63, 0) if track_states[col] else (63, 0, 0)
        lp.LedCtrlXY(col, 7, *color)

def update_active_matrix():
    """Refresh the LEDs for the currently selected clip matrix"""
    # Clear the previous matrix's LEDs
    for row in matrices[current_matrix]["rows"]:
        for col in matrices[current_matrix]["cols"]:
            lp.LedCtrlXY(col, row, 0, 0, 0)
    # Mock clip state example (replace with DAW sync logic)
    mock_clip_states = [
        [True, False, True, False, True, False, True],
        [False, True, False, True, False, True, False]
    ]
    # Draw clip states to the grid
    for row_idx, row in enumerate(matrices[current_matrix]["rows"]):
        for col_idx, col in enumerate(matrices[current_matrix]["cols"]):
            # Dim green for playing clips, yellow for unlaunched
            color = (0, 31, 0) if mock_clip_states[row_idx][col_idx] else (31, 31, 0)
            lp.LedCtrlXY(col, row, *color)

# Initialize the grid
update_stop_row()
update_active_matrix()

# Main loop to handle button presses
try:
    while True:
        button = lp.ButtonStateXY()
        if button:
            x, y, pressed = button
            # Handle stop row presses (bottom row, cols 0-6)
            if y == 7 and x < 7 and pressed:
                track_states[x] = not track_states[x]
                update_stop_row()
                # Replace this print with MIDI commands to your DAW
                print(f"Track {x+1}: {'Stopped' if not track_states[x] else 'Playing'}")
            # Handle navigation button (bottom-right corner)
            elif x == 7 and y == 7 and pressed:
                current_matrix = (current_matrix + 1) % 4
                update_active_matrix()
            # Handle clip launch presses in active matrix
            else:
                # Check if the pressed button is in the current matrix
                if y in matrices[current_matrix]["rows"] and x in matrices[current_matrix]["cols"]:
                    col_idx = matrices[current_matrix]["cols"].index(x)
                    row_idx = matrices[current_matrix]["rows"].index(y)
                    # Replace this print with MIDI clip launch commands
                    print(f"Launched Clip: Matrix {current_matrix+1}, Row {row_idx+1}, Col {col_idx+1}")
        time.sleep(0.01)
except KeyboardInterrupt:
    # Cleanup on exit
    lp.Reset()
    lp.Close()

• DAW Sync: To make this work with your DAW (Ableton, Logic, etc.), you'll need to:
  1. Send MIDI messages from the code to trigger clip launches/track stops
  2. Listen for MIDI feedback from the DAW to update your local track/clip state variables (so LEDs match actual DAW state)
• Launchpad Model Tweaks: If you're using a Launchpad Mini/Pro, adjust the LED color values and connection logic in the code—launchpad_py supports most models.
• Customization: Feel free to adjust the matrix positions, navigation button location, or LED colors to match your workflow.

内容的提问来源于stack exchange，提问作者Manish