我正在尝试重新实现我不久前成功完成的一些事情，但我只是做得不太对..
我使用的分形高度图生成算法本质上是递归菱形正方形算法。它似乎可以正常运行，但生成的地图“不太正确”....似乎没有成功访问网格中的每个点来确定颜色，并且地图中存在残留的“结构”这似乎与网格的递归方式有关。我不确定问题究竟在哪里/如何产生我所看到的。
我到目前为止的代码是，
import matplotlib.pyplot as plt
import matplotlib.cm as cm
from math import sqrt
from collections import namedtuple
import random
Coord=namedtuple('Coord','x y')
class Grid(object):
'''grid handedness, 0,0=topleft max,max=bottomr right'''
def __init__(self,x,y):
self.size_x=x
self.size_y=y
self.data=[ [0 for _ in xrange(x)] for _ in xrange(y) ]
def _render_to_text(self):
print '\n\n'
for row in self.data:
print [ int(n) for n in row ]
def _render_to_colormap(self):
plt.imshow(self.data, interpolation='nearest',cmap=cm.gist_rainbow)
plt.show()
def render(self):
self._render_to_colormap()
#self._render_to_text()
def make(self,coordinate,value):
self.data[coordinate.x][coordinate.y]=value
def make_new(self,coordinate,value):
if self.data[coordinate.x][coordinate.y]==0:
self.make(coordinate,value)
def get(self,coordinate):
return self.data[coordinate.x][coordinate.y]
class FractalHeightmap(object):
'''populates a 'grid' with a fractal heightmap'''
def __init__(self,grid,rng_seed,roughness,
corner_seeds=[(0,100),(0,100),(0,100),(0,100)],
max_depth=3):
self.grid=grid
self.max_depth=max_depth
self._set_initial_corners(corner_seeds)
self.roughness=roughness
self.generate_heightmap([Coord(0,0),
Coord(self.grid.size_x-1,0),
Coord(0,self.grid.size_y-1),
Coord(self.grid.size_x-1,self.grid.size_y-1)],1
)
def _set_initial_corners(self,corner_seeds):
tl,tr,bl,br=corner_seeds
seeds=[[tl,tr],[bl,br]]
for x_idx,x in enumerate([0,self.grid.size_x-1]):
for y_idx,y in enumerate([0,self.grid.size_y-1]):
try:
minval,maxval=seeds[x_idx][y_idx]
val=minval+(random.random()*(maxval-minval))
except ValueError:
val=seeds[x_idx][y_idx]
self.grid.make_new(Coord(x,y),val)
def generate_heightmap(self,corners,depth):
'''corners = (Coord(),Coord(),Coord(),Coord() / tl/tr/bl/br'''
if depth>self.max_depth: return
#
tl,tr,bl,br=corners
center=Coord((tr.x-tl.x)/2,(br.y-tr.y)/2)
#define edge center coordinates
top_c=Coord(tl.x+((tr.x-tl.x)/2),tl.y)
left_c=Coord(tl.x,tl.y+((bl.y-tl.y)/2))
right_c=Coord(tr.x,tr.y+((br.y-tr.y)/2))
bot_c=Coord(bl.x+((br.x-bl.x)/2),bl.y)
#calc the center and edge_center heights
avg=sum([self.grid.get(tl),
self.grid.get(tr),
self.grid.get(bl),
self.grid.get(br)]
)/4.0 ###NOTE, we can choose to use the current corners, the new edge-centers, or all
#currenty we use the current corners
#then do the edge centers
offset=((random.random())-.5)*self.roughness
self.grid.make_new(center,avg+offset)
#top_c
avg=sum([self.grid.get(tl),
self.grid.get(tr)]
)/2.0
offset=((random.random())-.5)*self.roughness
self.grid.make_new(top_c,avg+offset)
#left_c
avg=sum([self.grid.get(tl),
self.grid.get(bl)]
)/2.0
offset=((random.random())-.5)*self.roughness
self.grid.make_new(left_c,avg+offset)
#right_c
avg=sum([self.grid.get(tr),
self.grid.get(br)]
)/2.0
offset=((random.random())-.5)*self.roughness
self.grid.make_new(right_c,avg+offset)
#bot_c
avg=sum([self.grid.get(bl),
self.grid.get(br)]
)/2.0
offset=((random.random())-.5)*self.roughness
self.grid.make_new(bot_c,avg+offset)
self.generate_heightmap((tl,top_c,left_c,center),depth+1)
self.generate_heightmap((top_c,tr,center,right_c),depth+1)
self.generate_heightmap((left_c,center,bl,bot_c),depth+1)
self.generate_heightmap((center,right_c,bot_c,br),depth+1)
if __name__ == '__main__':
g_size=32 #//must be power of 2
g=Grid(g_size+1,g_size+1)
f=FractalHeightmap(g,1,10,max_depth=sqrt(g_size))
g.render()
如果您按原样运行它，您应该看到颜色图并了解它为什么不正确，将深度更改为 2 的不同幂以不同的方式显示它 - 值 256 及以上需要一段时间才能生成
非常感谢任何帮助。