62 lines
1.4 KiB
Python
62 lines
1.4 KiB
Python
import math
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import cairo
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class SnowflakeLayout:
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_BASE_RADIUS = 65
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_CHILDREN_FACTOR = 1
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_FLAKE_DISTANCE = 6
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def __init__(self):
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self._root = None
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self._r = 0
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def set_root(self, icon):
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self._root = icon
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def _layout_root(self, box):
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[width, height] = self._root.get_allocation()
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x = self._cx - (width / 2)
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y = self._cy - (height / 2)
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box.move(self._root, int(x), int(y))
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def _layout_child(self, box, child, index):
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r = self._r
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if (len(box.get_children()) > 10):
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r += SnowflakeLayout._FLAKE_DISTANCE * (index % 3)
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angle = 2 * math.pi / len(box.get_children()) * index
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[width, height] = child.get_allocation()
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x = self._cx + math.cos(angle) * r - (width / 2)
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y = self._cy + math.sin(angle) * r - (height / 2)
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box.move(child, int(x), int(y))
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def get_size(self, box):
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max_child_size = 0
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for child in box.get_children():
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[width, height] = child.get_allocation()
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max_child_size = max (max_child_size, width)
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max_child_size = max (max_child_size, height)
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return self._r * 2 + max_child_size + \
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SnowflakeLayout._FLAKE_DISTANCE * 2
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def layout(self, box):
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self._r = SnowflakeLayout._BASE_RADIUS + \
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SnowflakeLayout._CHILDREN_FACTOR * len(box.get_children())
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size = self.get_size(box)
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self._cx = size / 2
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self._cy = size / 2
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self._layout_root(box)
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index = 0
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for child in box.get_children():
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self._layout_child(box, child, index)
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index += 1
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