Initial python3 workpython3-port-try2

This is enough to get presentty to display the demo presentation all the
way through.  The Python3 version appears to have some slight
performance problems (or perhaps it's a difference in behaviour) during
transitions.  On displaying a new slide, the text pulses once (gets
brighter than it should be in its final state).

1 files changed, 18 insertions, 12 deletions

diff --git a/presentty/transition.py b/presentty/transition.py
index 5592cd9..1e9fbad 100644
--- a/presentty/transition.py
+++ b/presentty/transition.py
@@ -13,7 +13,11 @@
 # You should have received a copy of the GNU General Public License
 # along with this program.  If not, see <http://www.gnu.org/licenses/>.
 
+from __future__ import absolute_import, division, print_function
+
+import six
 import urwid
+from six.moves import range
 
 class Transition(urwid.Widget):
     def __init__(self, duration=0.4):
@@ -76,7 +80,9 @@ class DissolveTransition(Transition):
         buf = []
         for line in canvas.content():
             for (attr, cs, text) in line:
-                for char in unicode(text, 'utf8'):
+                if not isinstance(text, six.text_type):
+                    text = six.text_type(text, 'utf-8')
+                for char in text:
                     buf.append((attr, cs, char))
         return buf
 
@@ -87,9 +93,9 @@ class DissolveTransition(Transition):
             self._oldbuf = self._to_buf(old)
             self._newbuf = self._to_buf(new)
             self._cache_size = size
-        line_list = []
+        b_line_list = []
         attr_list = []
-        line_text = ''
+        b_line_text = b''
         line_attrs = []
         current_attr = [None, 0]
         current_rgb = None
@@ -104,11 +110,11 @@ class DissolveTransition(Transition):
                 oldrgb = background.get_rgb_values()
             if None in newrgb:
                 newrgb = background.get_rgb_values()
-            if newchar == ' ':
+            if newchar == b' ':
                 char = oldchar
                 charattr = oldattr
                 newrgb = newrgb[3:]*2
-            elif oldchar == ' ':
+            elif oldchar == b' ':
                 char = newchar
                 charattr = newattr
                 oldrgb = oldrgb[3:]*2
@@ -118,8 +124,8 @@ class DissolveTransition(Transition):
             else:
                 char = oldchar
                 charattr = oldattr
-            char = char.encode('utf8')
-            line_text += char
+            b_char = char.encode('utf8')
+            b_line_text += b_char
             rgb = []
             props = []
             if charattr.bold:
@@ -133,25 +139,25 @@ class DissolveTransition(Transition):
             for x in range(len(oldrgb)):
                 rgb.append(int(((newrgb[x]-oldrgb[x])*self.progress)+oldrgb[x])>>4)
             if current_rgb == rgb and current_props == props:
-                current_attr[1] += len(char)
+                current_attr[1] += len(b_char)
             else:
                 if current_attr[0]:
                     line_attrs.append(tuple(current_attr))
                 fg = ', '.join(props + ['#%x%x%x' % tuple(rgb[:3])])
                 bg = '#%x%x%x' % tuple(rgb[3:])
                 attr = urwid.AttrSpec(fg, bg)
-                current_attr = [attr, len(char)]
+                current_attr = [attr, len(b_char)]
                 current_rgb = rgb
                 current_props = props
             if (i+1) % size[0] == 0:
                 line_attrs.append(tuple(current_attr))
                 current_attr = [None, 0]
                 current_rgb = None
-                line_list.append(line_text)
-                line_text = ''
+                b_line_list.append(b_line_text)
+                b_line_text = b''
                 attr_list.append(line_attrs)
                 line_attrs = []
-        canvas = urwid.TextCanvas(line_list, attr_list)
+        canvas = urwid.TextCanvas(b_line_list, attr_list)
         return canvas
 
 class CutTransition(Transition):