import Image
import glob
class PackNode(object):
"""
Creates an area which can recursively pack other areas of smaller sizes into itself.
"""
def __init__(self, area):
#if tuple contains two elements, assume they are width and height, and origin is (0,0)
if len(area) == 2:
area = (0,0,area[0],area[1])
self.area = area
def __repr__(self):
return "<%s %s>" % (self.__class__.__name__, str(self.area))
def get_width(self):
return self.area[2] - self.area[0]
width = property(fget=get_width)
def get_height(self):
return self.area[3] - self.area[1]
height = property(fget=get_height)
def insert(self, area):
if hasattr(self, 'child'):
a = self.child[0].insert(area)
if a is None: return self.child[1].insert(area)
return a
area = PackNode(area)
if area.width <= self.width and area.height <= self.height:
self.child = [None,None]
self.child[0] = PackNode((self.area[0]+area.width, self.area[1], self.area[2], self.area[1] + area.height))
self.child[1] = PackNode((self.area[0], self.area[1]+area.height, self.area[2], self.area[3]))
return PackNode((self.area[0], self.area[1], self.area[0]+area.width, self.area[1]+area.height))
if __name__ == "__main__":
format = 'RGBA'
#size of the image we are packing into
size = 1024,1024
#get a list of PNG files in the current directory
names = glob.glob("*.png")
#create a list of PIL Image objects, sorted by size
images = sorted([(i.size[0]*i.size[1], name, i) for name,i in ((x,Image.open(x).convert(format)) for x in names)])
tree = PackNode(size)
image = Image.new(format, size)
#insert each image into the PackNode area
for area, name, img in images:
uv = tree.insert(img.size)
if uv is None: raise ValueError('Pack size too small.')
image.paste(img, uv.area)
image.show()
