Growing things | nebula
############################################################################# # Copyright (c) 2007 Tom De Smedt. __author__ = "Tom De Smedt" __version__ = "1.9.1" __copyright__ = "Copyright (c) 2007 Tom De Smedt" __license__ = "GPL" ############################################################################# try: # Try to render shadows using the colors library. colors = ximport("colors") colors.shadow(alpha=0.02, dx=30, dy=30) except: pass ############################################################################# # The geo library bundles the commands discussed in: # http://nodebox.net/code/index.php/Math from nodebox import geo def merge(points, x, y, vx, vy, reflected=False, d=0): """ Smooth curves from all points in the list to x, y. """ beginpath(0,0) for pt in points: if not reflected: vx0, vy0 = pt.ctrl1.x, pt.ctrl1.y else: vx0, vy0 = geo.reflect(pt.x, pt.y, pt.ctrl1.x, pt.ctrl1.y) moveto(pt.x, pt.y) curveto(vx0, vy0, vx, vy, x+random(-d,d), y+random(-d,d)) return endpath(draw=False) def points(n, vx, vy, h=(0.0,1.0), v=(0.0,1.0)): """ Random points in a relative h, v box with vx, vy handles. """ points = [] for i in range(n): pt = PathElement() pt.x = WIDTH*h[0] + random(WIDTH*(h[1]-h[0])) pt.y = HEIGHT*v[0] + random(HEIGHT*(v[1]+v[0])) pt.ctrl1.x = pt.x+vx pt.ctrl1.y = pt.y+vy points.append(pt) return points ############################################################################# def nebula(clr, bg=True, n=100, d=300, angle=0.5, iterations=100, tonality=0.1, growth=[1.01, 1.01, 0.98]): """ Draws a set of elegant curves in subtle shades of the given color. If bg is True, fills the background with a dark variation of the color. Increasing n produces more curves. Decreasing d keeps curves together more tightly. The angle controls how pattern copies are placed on top of each other. The number of iterations are the number of copies of curve patterns. More iterations yield thicker compositions. The tonality controls the diversity in color. The growth parameter is a list of 3 numbers defining how each of the three layers of curves is scaled. """ def _wrap_around(n, base=1): # e.g. if base is 5, 7 is returned as 2. if n < 0: return base-n if n > base: return n-base return n def _draw_transformed(path, dx=0, dy=0, angle=0, scaling=1.0): try: angle = angle() except: pass rotate(angle) drawpath(path.copy()) scale(scaling) translate(dx, dy) colormode(HSB) if bg: background( clr.hue, clr.saturation, max(0.15, clr.brightness*0.15) ) else: background(None) strokewidth(0.1) nofill() autoclosepath(False) # Create a number of points in a portion of the canvas. # The points all have the same handle vector. # Then, draw a line from each point to a focus point. h = (random(1-random(0.2)), random(0.2)) v = (random(1-random(0.2)), random(0.2)) pts = points(n, random(-d,d), random(-d,d), h, v) x, y = random(WIDTH), random(HEIGHT) vx, vy = x+random(-d/2,d*2), y+random(-d/4,d/4) path = merge(pts, x, y, vx, vy, d=random(d/2)) # Draw rotating versions of this path # that increment in size and horizontal position. # Colors are dark with variations in hue. #transform(CORNER) direction = choice((-1,1)) for i in range(iterations/2): stroke(_wrap_around((clr.hue + random(tonality)*direction)), clr.saturation, clr.brightness * (0.4 + random(0.6)), random(0.25)) _draw_transformed(path, 1.5, 0, angle, growth[0]) for i in range(choice((2,3))): reset() # Draw lines from the foucs point to new points, # with their handles reflected from the focus' handles. h = (random(1-random(0.2)), random(0.2)) v = (random(1-random(0.2)), random(0.2)) pts = points(n, random(-d,d), random(-d,d), h, v) vx, vy = geo.reflect(x, y, vx, vy) path = merge(pts, x, y, vx, vy, reflected=True, d=10) # Incremental variations of the path. # Colors are light and desaturated. for i in range(iterations/2): stroke(clr.hue, clr.saturation + random(-0.6), random(0.2) + 0.8, random(0.25)) _draw_transformed(path, random(), random(), angle, growth[1]) # Variations that decrement in size. # Colors are light with variations in hue. direction = choice((-1,1)) for i in range(iterations): stroke(_wrap_around((clr.hue + random(tonality)*direction)), clr.saturation + random(-0.2), random(0.2) + 0.8, random(0.25)) _draw_transformed(path, 1.5, 0, angle, growth[2]) reset() ############################################################################# # Set a base color for the nebula. colormode(HSB) clr = color(0.1, 0.3, 1) size(700,700) nebula(clr)
