More Colors Animate Shader Toy.

# on a 40 x 40 grid
# define a draw(x,y) function that 
# returns the color at x,y
# colors = is a list [r,g,b], each value ranging from 0 to 255
# and a global time variable t that tics up 1/10th of a second

import random
import math

def draw(x, y, t):
    height = 40
    tail_length = 10

# Seed randomness for consistent behavior per column
    random.seed(x)

# Determine stream cycle duration (when head moves from top to fully offscreen)
    speed = random.uniform(0.5, 1.5)
    stream_duration = (height + tail_length + random.randint(0, 20)) / speed  # extra randomness to avoid sync

# The number of complete stream cycles since time 0
    cycle = int(t // stream_duration)

# Each cycle gets a new offset
    random.seed(x + cycle * 1000)  # reseed for variation in new stream
    offset = random.uniform(-tail_length, height)  # allow it to start offscreen
    speed = random.uniform(0.5, 1.5)  # fresh speed each time

# Position of the stream head in current cycle
    t_in_cycle = t % stream_duration
    head = offset + t_in_cycle * speed

# Calculate the distance from head
    distance = head - y
    u = random.random()
    if 0 <= distance <= tail_length:
        # Trail with fading green
        brightness = 1.0 - distance / tail_length
        g = int(255 * brightness/2) * u
        return (0, g, 0)
    elif -1 <= distance < 0:
        # Bright leading character
        return (180 * u, 255 * u, 100 * u)
    else:
        # Background
        return (0, 0, 0)

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