Ticket #2235: 0001-add-spiral-to-ring-layout-as-number-of-icons-increas.patch

src/jarabe/desktop/favoriteslayout.py

@@ -198 +198 @@
 _ICON_SPACING_FACTORS = [1.5, 1.4, 1.3, 1.2, 1.15, 1.1, 1.05, 1.0]
 
 
-class RingLayout(FavoritesLayout):
+class BasicRingLayout(FavoritesLayout):
     """Lay out icons in a ring around the XO man."""
 
-    __gtype_name__ = 'RingLayout'
+    __gtype_name__ = 'BasicRingLayout'
     icon_name = 'view-radial'
     """Name of icon used in home view dropdown palette."""
-    key = 'ring-layout'
+    key = 'basic-ring-layout'
     """String used in profile to represent this view."""
     # TRANS: label for the ring layout in the favorites view
     palette_name = _('Ring')
@@ -312 +312 @@
             return 0
 
 
+_MIMIMUM_RADIUS_ENCROACHMENT = 0.75
+_INITIAL_ANGLE = math.pi
+_SPIRAL_SPACING_FACTORS = [1.5, 1.5, 1.5, 1.4, 1.35, 1.3, 1.25, 1.2]
+
+
+class RingLayout(BasicRingLayout):
+    """ Variation of Basic Ring that morphs into a spiral as
+    the number of icons increases beyond the capacity of the
+    STANDARD_ICON_SIZE. """
+
+    __gtype_name__ = 'RingLayout'
+    icon_name = 'view-radial'
+    """Name of icon used in home view dropdown palette."""
+    key = 'ring-layout'
+    """String used in profile to represent this view."""
+
+    def __init__(self):
+        BasicRingLayout.__init__(self)
+        self._locked_children = {}
+        self._spiral_mode = False
+
+    def _calculate_radius_and_icon_size(self, children_count):
+        """ Adjust the ring or spiral radius and icon size as needed. """
+        self._spiral_mode = False
+        # Begin by increasing the radius.
+        distance = style.MEDIUM_ICON_SIZE + style.DEFAULT_SPACING * \
+            _ICON_SPACING_FACTORS[_ICON_SIZES.index(style.MEDIUM_ICON_SIZE)]
+        radius = max(children_count * distance / (2 * math.pi), _MINIMUM_RADIUS)
+        if radius < _MAXIMUM_RADIUS:
+            return radius, style.MEDIUM_ICON_SIZE
+
+        # Continue by shrinking the icon size.
+        radius = _MAXIMUM_RADIUS
+        distance = radius * (2 * math.pi) / children_count
+        icon_size = int(distance - style.DEFAULT_SPACING * \
+            _ICON_SPACING_FACTORS[_ICON_SIZES.index(style.STANDARD_ICON_SIZE)])
+        if icon_size >= style.STANDARD_ICON_SIZE:
+            return radius, icon_size
+
+        # Finally, switch to a spiral.
+        self._spiral_mode = True
+        icon_size = style.STANDARD_ICON_SIZE
+        angle, radius = self._calculate_angle_and_radius(children_count,
+                                                         icon_size)
+        while radius > _MAXIMUM_RADIUS:
+            i = _ICON_SIZES.index(icon_size)
+            if i < len(_ICON_SIZES) - 1:
+                icon_size = _ICON_SIZES[i + 1]
+                angle, radius = self._calculate_angle_and_radius(
+                    children_count, icon_size)
+            else:
+                break
+        return radius, icon_size
+
+    def _calculate_position(self, radius, icon_size, icon_index, children_count,
+                            sin=math.sin, cos=math.cos):
+        """ Calculate an icon position on a circle or a spiral. """
+        width, height = self.box.get_allocation()
+        if self._spiral_mode:
+            min_width_, box_width = self.box.get_width_request()
+            min_height_, box_height = self.box.get_height_request(box_width)
+            angle, radius = self._calculate_angle_and_radius(icon_index,
+                                                             icon_size)
+            x, y = self._convert_from_polar_to_cartesian(angle, radius,
+                                                         icon_size,
+                                                         width, height)
+        else:
+            angle = icon_index * (2 * math.pi / children_count) - math.pi / 2
+            x = radius * cos(angle) + (width - icon_size) / 2
+            y = radius * sin(angle) + (height - icon_size - \
+                                       (style.GRID_CELL_SIZE / 2)) / 2
+        return x, y
+
+    def _convert_from_polar_to_cartesian(self, angle, radius, icon_size, width,
+                                         height):
+        """ Convert angle, radius to x, y """
+        x = int(math.sin(angle) * radius)
+        y = int(math.cos(angle) * radius)
+        x = - x + (width - icon_size) / 2
+        y = y + (height - icon_size - (style.GRID_CELL_SIZE / 2)) / 2
+        return x, y
+
+    def _calculate_angle_and_radius(self, icon_count, icon_size):
+        """ Based on icon_count and icon_size, calculate radius and angle. """
+        spiral_spacing = _SPIRAL_SPACING_FACTORS[_ICON_SIZES.index(icon_size)]
+        icon_spacing = icon_size + style.DEFAULT_SPACING * \
+            _ICON_SPACING_FACTORS[_ICON_SIZES.index(icon_size)]
+        angle = _INITIAL_ANGLE
+        radius = _MINIMUM_RADIUS - (icon_size * _MIMIMUM_RADIUS_ENCROACHMENT)
+        for i in range(icon_count):
+            circumference = radius * 2 * math.pi
+            n = circumference / icon_spacing
+            angle += (2 * math.pi / n)
+            radius += (float(icon_spacing) * spiral_spacing / n)
+        return angle, radius
+
+
 _SUNFLOWER_CONSTANT = style.STANDARD_ICON_SIZE * .75
 """Chose a constant such that STANDARD_ICON_SIZE icons are nicely spaced."""
 
@@ -337 +434 @@
 Calculation: math.radians(360) / ( _GOLDEN_RATIO * _GOLDEN_RATIO )
 """
 
-class SunflowerLayout(RingLayout):
+class SunflowerLayout(BasicRingLayout):
     """Spiral layout based on Fibonacci ratio in phyllotaxis.
 
     See http://algorithmicbotany.org/papers/abop/abop-ch4.pdf
@@ -356 +453 @@
     """String used to identify this layout in home view dropdown palette."""
 
     def __init__(self):
-        RingLayout.__init__(self)
+        BasicRingLayout.__init__(self)
         self.skipped_indices = []
 
     def _calculate_radius_and_icon_size(self, children_count):
@@ -407 +504 @@
 
             return x, y
 
-class BoxLayout(RingLayout):
+class BoxLayout(BasicRingLayout):
     """Lay out icons in a square around the XO man."""
 
     __gtype_name__ = 'BoxLayout'
@@ -423 +520 @@
     """String used to identify this layout in home view dropdown palette."""
 
     def __init__(self):
-        RingLayout.__init__(self)
+        BasicRingLayout.__init__(self)
 
     def _calculate_position(self, radius, icon_size, index, children_count,
                             sin=None, cos=None):
@@ -444 +541 @@
         cos = lambda r: cos_d(math.degrees(r))
         sin = lambda r: cos_d(math.degrees(r) - 90)
 
-        return RingLayout._calculate_position\
+        return BasicRingLayout._calculate_position\
                (self, radius, icon_size, index, children_count,
                 sin=sin, cos=cos)
 
-class TriangleLayout(RingLayout):
+class TriangleLayout(BasicRingLayout):
     """Lay out icons in a triangle around the XO man."""
 
     __gtype_name__ = 'TriangleLayout'
@@ -464 +561 @@
     """String used to identify this layout in home view dropdown palette."""
 
     def __init__(self):
-        RingLayout.__init__(self)
+        BasicRingLayout.__init__(self)
 
     def _calculate_radius_and_icon_size(self, children_count):
         # use slightly larger minimum radius than parent, because sides
         # of triangle come awful close to the center.
         radius, icon_size = \
-            RingLayout._calculate_radius_and_icon_size(self, children_count)
+            BasicRingLayout._calculate_radius_and_icon_size(self,
+                                                            children_count)
         return max(radius, _MINIMUM_RADIUS + style.MEDIUM_ICON_SIZE), icon_size
 
     def _calculate_position(self, radius, icon_size, index, children_count,
@@ -501 +599 @@
         cos = lambda r: cos_d(math.degrees(r))
         sin = lambda r: sin_d(math.degrees(r))
 
-        return RingLayout._calculate_position\
+        return BasicRingLayout._calculate_position\
                (self, radius, icon_size, index, children_count,
                 sin=sin, cos=cos)