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October 25, 2018 16:34
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gray_scott.py
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| #!python3 | |
| from __future__ import print_function | |
| import numpy as np | |
| try: | |
| from scene import * | |
| ios = True | |
| except: | |
| ios = False | |
| #ios = False | |
| f, k = 0.022, 0.051 # stripe | |
| #f, k = 0.035, 0.065 # spot | |
| f, k = 0.04, 0.06 # amorphus | |
| #f, k = 0.012, 0.05 # wandering bubbles | |
| #f, k = 0.025, 0.05 # waves | |
| class Sim: | |
| def __init__(self, rows, cols, f=0.022, k=0.051, dx=0.01, dt=1,Du=2e-5, Dv=1e-5, sqsize=10): | |
| self.shape = (rows,cols) | |
| self.us = np.ones((rows, cols)) | |
| self.vs = np.zeros((rows, cols)) | |
| self.sqsize = sqsize | |
| self.us[rows//2-sqsize//2:rows//2+sqsize//2, | |
| cols//2-sqsize//2:cols//2+sqsize//2] = 0.5 | |
| self.vs[rows//2-sqsize//2:rows//2+sqsize//2, | |
| cols//2-sqsize//2:cols//2+sqsize//2] = 0.5 | |
| self.us += np.random.randn(rows, cols)*0.1 | |
| self.vs += np.random.randn(rows, cols)*0.1 | |
| self.dt = dt | |
| self.dx = dx | |
| self.f = f | |
| self.k = k | |
| self.Du = Du | |
| self.Dv = Dv | |
| def step(self, n=1): | |
| for i in range(n): | |
| u = self.us | |
| v = self.vs | |
| lu = (np.roll(u,1,axis=0)+np.roll(u,-1,axis=0) | |
| +np.roll(u,1,axis=1)+np.roll(u,-1,axis=1)-4*u)/(self.dx*self.dx) | |
| lv = (np.roll(v,1,axis=0)+np.roll(v,-1,axis=0) | |
| +np.roll(v,1,axis=1)+np.roll(v,-1,axis=1)-4*v)/(self.dx*self.dx) | |
| dudt = self.Du*lu-u*v*v+self.f*(1-u) | |
| dvdt = self.Dv*lv+u*v*v-(self.f+self.k)*v | |
| self.us += dudt*self.dt | |
| self.vs += dvdt*self.dt | |
| def set(self, x, y, u, v): | |
| self.us[y,x]=u | |
| self.vs[y,x]=v | |
| if ios: | |
| def clip(x, min, max): | |
| return np.minimum(max, np.maximum(min, x)) | |
| def draw_grids(size,rows,cols): | |
| fill(0,0,0) | |
| stroke(0,0,0) | |
| stroke_weight(1) | |
| for i in range(0,cols+1): | |
| line(i*size,0,i*size,rows*size) | |
| for i in range(0,rows+1): | |
| line(0,i*size,cols*size,i*size) | |
| def draw_elem(x,y,size,rows,cols, color): | |
| fill(*color) | |
| #print (color, end=',') | |
| # ellipse(x*size+size/4.0,y*size+size/4.0,size/2.0,size/2.0) | |
| rect(x*size,y*size,size,size) | |
| class GridScene(Scene): | |
| def __init__(self, wait, cellsize): | |
| super(GridScene, self).__init__() | |
| self.wait = wait | |
| self.cellsize = cellsize | |
| self.sim =None | |
| def setup(self): | |
| self.cols = int(self.size.w/self.cellsize) | |
| self.rows = int(self.size.h/self.cellsize) | |
| self.sim = Sim(self.rows, self.cols, f, k) | |
| self.prev_draw_time = 0 | |
| self.hw = int(self.size.w/2) | |
| self.hh = int(self.size.h/2) | |
| self.locs = {} | |
| def coord_screen_to_board(self,loc): | |
| x, y = int(loc.x/self.cellsize), \ | |
| int(loc.y/self.cellsize) | |
| return x,y | |
| def touch_began(self, touch): | |
| loc = touch.location | |
| x, y = self.coord_screen_to_board(loc) | |
| self.sim.set(x, y, 0.5, 0.5) | |
| self.locs[touch.touch_id] = loc | |
| def touch_moved(self, touch): | |
| prex, prey = self.coord_screen_to_board( | |
| self.locs[touch.touch_id]) | |
| curx, cury = self.coord_screen_to_board(touch.location) | |
| dx, dy = curx - prex, cury - prey | |
| l = max(abs(dx),abs(dy)) | |
| if l != 0: | |
| fx, fy = float(dx)/l, float(dy)/l | |
| for i in range(l): | |
| self.sim.set(prex + int(fx*i), prey + int(fy*i), 0.5, 0.5) | |
| self.sim.set(curx, cury, 0.5, 0.5) | |
| self.locs[touch.touch_id] = touch.location | |
| def touch_ended(self, touch): | |
| if touch.touch_id in self.locs: del self.locs[touch.touch_id] | |
| def draw(self): | |
| background('white') | |
| if self.sim: | |
| for y in range(self.rows): | |
| for x in range(self.cols): | |
| c = [self.sim.us[y,x], self.sim.us[y,x], self.sim.us[y, x]] | |
| draw_elem(x, y, self.cellsize, self.rows, self.cols, c) | |
| #if self.t - self.prev_draw_time > self.wait and len(self.touches) == 0: | |
| if self.t - self.prev_draw_time > self.wait: | |
| self.prev_draw_time = self.t | |
| self.sim.step(8) | |
| run(GridScene(0.1, 4)) | |
| else: | |
| import matplotlib.pyplot as plt | |
| rows, cols = 128,128 | |
| sim = Sim(rows, cols, f, k) | |
| for i in range(1000): | |
| fig = plt.figure() | |
| plt.axis('off') | |
| plt.imshow(sim.us, cmap='gray') | |
| plt.show() | |
| plt.close(fig) | |
| #print(sim.us) | |
| sim.step(16) |
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