Lotus Rosettes for Processing Python Mode

py_lotusrosettes.pyde

"""
   Under Creative Commons License
   https:#creativecommons.org/licenses/by-sa/4.0/
   Ported for Processing Python Mode py.processing.org <- for Processing IDE
   by Alexandre Villares abav.lugaralgum.com, 9-Oct-2018
   Based upon code for p5js.org at https://jcponce.github.io/misc/lotusrosettes.html 
   by Juan Carlos Ponce Campuzano, 9-Oct-2018
   Based upon Dan Anderson's code
   https:#www.openprocessing.org/sketch/519299
"""

gridsize = 13

def  setup():
    size(550, 550)
    colorMode(HSB)

def  draw():
    background(0)
    gridsize = int(map(mouseX, 0, width, 4, 13))
    textAlign(LEFT, CENTER)
    stroke(0, 0, 80)
    fill(0, 0, 80)
    #text("r=asin(cos(a/b * t))", 6, 0 + width / (2 * gridsize))
    textAlign(CENTER, CENTER)
    text("a", width / 2, height / (6 * gridsize))
    text("b", width / (6 * gridsize), height / 2)
    
    for a in range(1, gridsize+1):
        for b in range(1, gridsize+1):
            cx = map(a, 1, gridsize, 0 + width / gridsize, width - width / gridsize)
            cy = map(b, gridsize, 1, height - height / gridsize, 0 + height / gridsize)
            
            if (a == 1):
                text(str(b), cx - width / (1.4 * gridsize), cy)
                text(str(b), cy, cx - height / (1.4 * gridsize))                        
            r = 0.25 * width / (gridsize + 1)
            
            beginShape()
            noFill()
            t = 0
            ox = cx + r * asin(cos(1.0 * a / b * t)) * cos(t)
            oy = cy + r * asin(cos(1.0 * a / b * t)) * sin(t)
            done = False
            while t < 4 * gridsize * TWO_PI and not done:
                x = cx + r * asin(cos(1.0 * a / b * t)) * cos(t)
                y = cy + r * asin(cos(1.0 * a / b * t)) * sin(t)
                stroke(cx, cy, 255)
                vertex(x, y)                
                if ((abs(x - ox) + abs(y - oy) < 0.05) and (t > TWO_PI / 150)):
                    done = True
                t += TWO_PI / 300
            endShape(OPEN)