Move the layouts to be box and subclass them.

1 files changed, 101 insertions, 0 deletions

diff --git a/sugar/graphics/spreadbox.py b/sugar/graphics/spreadbox.py
new file mode 100644
index 0000000..456aeca
--- /dev/null
+++ b/sugar/graphics/spreadbox.py
@@ -0,0 +1,101 @@
+import random
+import math
+
+import cairo
+import hippo
+
+_DISTANCE_THRESHOLD = 120.0
+
+class SpreadBox(hippo.CanvasBox, hippo.CanvasItem):
+	__gtype_name__ = 'SugarSpreadBox'
+
+	def __init__(self, **kwargs):
+		hippo.CanvasBox.__init__(self, **kwargs)
+
+		self._items_to_position = []
+		self._spread_on_add = False
+
+	def add(self, item):
+		self._items_to_position.append(item)
+		self.append(item, hippo.PACK_FIXED)
+		if self._spread_on_add:
+			self.spread()
+
+	def spread(self):
+		self._spread_on_add = True
+
+		[width, height] = self.get_allocation()
+		for item in self._items_to_position:
+			x = int(random.random() * width)
+			y = int(random.random() * height)
+
+			[x, y] = self._clamp_position(item, x, y)
+			self.move(item, x, y)
+
+		self._items_to_position = []
+
+	def _get_distance(self, icon1, icon2):
+		[icon1_x, icon1_y] = self.get_position(icon1)
+		[icon2_x, icon2_y] = self.get_position(icon2)
+
+		a = icon1_x - icon2_x
+		b = icon1_y - icon2_y
+
+		return math.sqrt(a * a  + b * b)
+
+	def _get_repulsion(self, icon1, icon2):
+		[icon1_x, icon1_y] = self.get_position(icon1)
+		[icon2_x, icon2_y] = self.get_position(icon2)
+
+		f_x = icon1_x - icon2_x
+		f_y = icon1_y - icon2_y
+
+		return [f_x, f_y]
+
+	def _clamp_position(self, icon, x, y):
+		x = max(0, x)
+		y = max(0, y)
+
+		[item_w, item_h] = icon.get_allocation()
+		[box_w, box_h] = self.get_allocation()
+
+		x = min(box_w - item_w, x)
+		y = min(box_h - item_h, y)
+
+		return [x, y]
+
+	def _spread_icons(self):
+		stable = True
+
+		for icon1 in self.get_children():
+			vx = 0
+			vy = 0
+
+			[x, y] = self.get_position(icon1)
+
+			for icon2 in self.get_children():
+				if icon1 != icon2:
+					distance = self._get_distance(icon1, icon2)
+					if distance <= _DISTANCE_THRESHOLD:
+						stable = False
+						[f_x, f_y] = self._get_repulsion(icon1, icon2)
+						vx += f_x
+						vy += f_y
+
+			new_x = x + vx
+			new_y = y + vy
+
+			[new_x, new_y] = self._clamp_position(icon1, new_x, new_y)
+
+			self.move(icon1, new_x, new_y)
+
+			return stable
+
+	def do_allocate(self, width, height):
+		hippo.CanvasBox.do_allocate(self, width, height)
+
+		tries = 10
+		stable = self._spread_icons()
+		while not stable and tries > 0:
+			stable = self._spread_icons()
+			tries -= 1