"""
Plasmas with Palette Looping
https://lodev.org/cgtutor/plasma.html#Plasmas_with_Palette_Looping_
"""

pal = [0] * 128
r = 42
g = 84
b = 126
rd = gd = bd = False

def setup():
    global buffer
    size(600, 600)
    frameRate(25)
    buffer = [None] * width * height
    for x in range(width):
        for y in range(width):
            value = int(((128 + (128 * sin(x / 32.0)))
                         + (128 + (128 * cos(y / 32.0)))
                         + (128 + (128 * sin(sqrt((x * x + y * y)) / 32.0)))) / 4)
            buffer[x + y * width] = value

def draw():
    global r, g, b, rd, gd, bd
    if r > 128: rd = True
    if not rd: r += 1
    else: r-=1
    if r < 0: rd = False
    if g > 128: gd = True
    if not gd: g += 1
    else: g- = 1
    if r < 0: gd = False
    if b > 128: bd = True
    if not bd: b += 1
    else: b- = 1
    if b < 0: bd = False

    for i in range(128):
          s_1 = sin(i * PI / 25)
          s_2 = sin(i * PI / 50 + PI / 4)
          pal[i] = color(r + s_1 * 128, g + s_2 * 128, b + s_1 * 128)

    loadPixels()
    for i, b in enumerate(buffer):
          pixels[i] = pal[(b + frameCount) % 127]
    updatePixels()