diff options
Diffstat (limited to 'lib/sugar/graphics/spreadlayout.py')
| -rw-r--r-- | lib/sugar/graphics/spreadlayout.py | 239 |
1 files changed, 239 insertions, 0 deletions
diff --git a/lib/sugar/graphics/spreadlayout.py b/lib/sugar/graphics/spreadlayout.py new file mode 100644 index 0000000..7bd1ff1 --- /dev/null +++ b/lib/sugar/graphics/spreadlayout.py @@ -0,0 +1,239 @@ +# Copyright (C) 2007 Red Hat, Inc. +# +# This library is free software; you can redistribute it and/or +# modify it under the terms of the GNU Lesser General Public +# License as published by the Free Software Foundation; either +# version 2 of the License, or (at your option) any later version. +# +# This library is distributed in the hope that it will be useful, +# but WITHOUT ANY WARRANTY; without even the implied warranty of +# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU +# Lesser General Public License for more details. +# +# You should have received a copy of the GNU Lesser General Public +# License along with this library; if not, write to the +# Free Software Foundation, Inc., 59 Temple Place - Suite 330, +# Boston, MA 02111-1307, USA. + +from numpy import array +from random import random + +import hippo +import gobject +import gtk + +_PLACE_TRIALS = 20 +_MAX_WEIGHT = 255 +_CELL_SIZE = 4 + +class _Grid(gobject.GObject): + __gsignals__ = { + 'child-changed' : (gobject.SIGNAL_RUN_FIRST, + gobject.TYPE_NONE, + ([gobject.TYPE_PYOBJECT])) + } + def __init__(self, width, height): + gobject.GObject.__init__(self) + + self.width = width + self.height = height + self._children = [] + self._collisions = [] + self._collisions_sid = 0 + + self._array = array([0], dtype='b') + self._array.resize(width * height) + + def add(self, child, width, height): + trials = _PLACE_TRIALS + weight = _MAX_WEIGHT + while trials > 0 and weight: + x = int(random() * (self.width - width)) + y = int(random() * (self.height - height)) + + rect = gtk.gdk.Rectangle(x, y, width, height) + new_weight = self._compute_weight(rect) + if weight > new_weight: + weight = new_weight + + trials -= 1 + + child.grid_rect = rect + child.locked = False + + self._add_child(child) + + if weight > 0: + self._detect_collisions(child) + + def remove(self, child): + self._children.remove(child) + self._remove_weight(child.grid_rect) + child.grid_rect = None + + def _add_child(self, child): + self._children.append(child) + self.add_weight(child.grid_rect) + + def _move_child(self, child, new_rect): + self._remove_weight(child.grid_rect) + self.add_weight(new_rect) + + child.grid_rect = new_rect + + self.emit('child-changed', child) + + def _shift_child(self, child): + rect = child.grid_rect + weight = self._compute_weight(rect) + new_rects = [] + + if (rect.x + rect.width < self.width - 1): + new_rects.append(gtk.gdk.Rectangle(rect.x + 1, rect.y, + rect.width, rect.height)) + + if (rect.x - 1 > 0): + new_rects.append(gtk.gdk.Rectangle(rect.x - 1, rect.y, + rect.width, rect.height)) + + if (rect.y + rect.height < self.height - 1): + new_rects.append(gtk.gdk.Rectangle(rect.x, rect.y + 1, + rect.width, rect.height)) + + if (rect.y - 1 > 0): + new_rects.append(gtk.gdk.Rectangle(rect.x, rect.y - 1, + rect.width, rect.height)) + + best_rect = None + for new_rect in new_rects: + new_weight = self._compute_weight(new_rect) + if new_weight < weight: + best_rect = new_rect + weight = new_weight + + if best_rect: + self._move_child(child, best_rect) + + return weight + + + def _solve_collisions(self): + for collision in self._collisions[:]: + weight = self._shift_child(collision) + if not weight: + self._collisions.remove(collision) + + return (len(self._collisions) > 0) + + def _detect_collisions(self, child): + collision_found = False + for c in self._children: + intersection = child.grid_rect.intersect(c.grid_rect) + if c != child and intersection.width > 0: + if c not in self._collisions: + collision_found = True + self._collisions.append(c) + + if collision_found: + if child not in self._collisions: + self._collisions.append(child) + +# if len(self._collisions) and not self._collisions_sid: +# self._collisions_sid = gobject.idle_add(self._solve_collisions) + + def add_weight(self, rect): + for i in range(rect.x, rect.x + rect.width): + for j in range(rect.y, rect.y + rect.height): + self[j, i] += 1 + + def _remove_weight(self, rect): + for i in range(rect.x, rect.x + rect.width): + for j in range(rect.y, rect.y + rect.height): + self[j, i] -= 1 + + def _compute_weight(self, rect): + weight = 0 + + for i in range(rect.x, rect.x + rect.width): + for j in range(rect.y, rect.y + rect.height): + weight += self[j, i] + + return weight + + def __getitem__(self, (row, col)): + return self._array[col + row * self.width] + + def __setitem__(self, (row, col), value): + self._array[col + row * self.width] = value + + +class SpreadLayout(gobject.GObject,hippo.CanvasLayout): + __gtype_name__ = 'SugarSpreadLayout' + def __init__(self): + gobject.GObject.__init__(self) + + min_width, width = self.do_get_width_request() + min_height, height = self.do_get_height_request(width) + + self._grid = _Grid(width / _CELL_SIZE, height / _CELL_SIZE) + self._grid.connect('child-changed', self._grid_child_changed_cb) + + def add_center(self, child): + self._box.append(child) + + width, height = self._get_child_grid_size(child) + rect = gtk.gdk.Rectangle(int((self._grid.width - width) / 2), + int((self._grid.height - height) / 2), + width + 1, height + 1) + self._grid.add_weight(rect) + + box_child = self._box.find_box_child(child) + box_child.grid_rect = None + + def add(self, child): + self._box.append(child) + + width, height = self._get_child_grid_size(child) + box_child = self._box.find_box_child(child) + self._grid.add(box_child, width, height) + + def remove(self, child): + box_child = self._box.find_box_child(child) + self._grid.remove(box_child) + + self._box.remove(child) + + def do_set_box(self, box): + self._box = box + + def do_get_height_request(self, for_width): + return 0, gtk.gdk.screen_height() + + def do_get_width_request(self): + return 0, gtk.gdk.screen_width() + + def do_allocate(self, x, y, width, height, + req_width, req_height, origin_changed): + for child in self._box.get_layout_children(): + rect = child.grid_rect + if child.grid_rect: + child.allocate(rect.x * _CELL_SIZE, + rect.y * _CELL_SIZE, + rect.width * _CELL_SIZE, + rect.height * _CELL_SIZE, + origin_changed) + else: + min_w, child_width = child.get_width_request() + min_h, child_height = child.get_height_request(child_width) + child.allocate(x + (width - child_width) / 2, + y + (height - child_height) / 2, + child_width, child_height, origin_changed) + + def _get_child_grid_size(self, child): + min_width, width = child.get_width_request() + min_height, height = child.get_height_request(width) + + return int(width / _CELL_SIZE), int(height / _CELL_SIZE) + + def _grid_child_changed_cb(self, grid, box_child): + box_child.item.emit_request_changed() |