sugar-toolkit-gtk3/sugar/graphics/spreadlayout.py
2006-10-05 18:32:35 +02:00

87 lines
1.7 KiB
Python

import random
import math
import cairo
_DISTANCE_THRESHOLD = 120.0
class SpreadLayout:
def __init__(self):
pass
def _get_distance(self, box, icon1, icon2):
[icon1_x, icon1_y] = box.get_position(icon1)
[icon2_x, icon2_y] = box.get_position(icon2)
a = icon1_x - icon2_x
b = icon1_y - icon2_y
return math.sqrt(a * a + b * b)
def _get_repulsion(self, box, icon1, icon2):
[icon1_x, icon1_y] = box.get_position(icon1)
[icon2_x, icon2_y] = box.get_position(icon2)
f_x = icon1_x - icon2_x
f_y = icon1_y - icon2_y
return [f_x, f_y]
def _clamp_position(self, box, icon, x, y):
x = max(0, x)
y = max(0, y)
[item_w, item_h] = icon.get_allocation()
[box_w, box_h] = box.get_allocation()
x = min(box_w - item_w, x)
y = min(box_h - item_h, y)
return [x, y]
def _spread_icons(self, box):
stable = True
for icon1 in box.get_children():
vx = 0
vy = 0
[x, y] = box.get_position(icon1)
for icon2 in box.get_children():
if icon1 != icon2:
distance = self._get_distance(box, icon1, icon2)
if distance <= _DISTANCE_THRESHOLD:
stable = False
[f_x, f_y] = self._get_repulsion(box, icon1, icon2)
vx += f_x
vy += f_y
new_x = x + vx
new_y = y + vy
[new_x, new_y] = self._clamp_position(box, icon1, new_x, new_y)
box.move(icon1, new_x, new_y)
return stable
def layout(self, box):
[width, height] = box.get_allocation()
for item in box.get_children():
[item_w, item_h] = item.get_allocation()
x = int(random.random() * width)
y = int(random.random() * height)
[x, y] = self._clamp_position(box, item, x, y)
box.move(item, x, y)
tries = 10
stable = self._spread_icons(box)
while not stable and tries > 0:
stable = self._spread_icons(box)
tries -= 1