Initial commit

1 files changed, 273 insertions, 0 deletions

diff --git a/ImageView.py b/ImageView.py
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index 0000000..491a79a
--- /dev/null
+++ b/ImageView.py
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+# Copyright (C) 2008, One Laptop Per Child
+# Author: Sayamindu Dasgupta <sayamindu@laptop.org>
+#
+# This program is free software; you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation; either version 2 of the License, or
+# (at your option) any later version.
+#
+# This program 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 General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program; if not, write to the Free Software
+# Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
+
+from __future__ import division
+
+import gtk
+from gtk import gdk
+import cairo
+import gobject
+
+import sys
+import logging
+
+import random
+
+class ImageViewer(gtk.DrawingArea):
+    __gsignals__ = {
+        'expose-event':   'override',
+        'zoom-changed': (gobject.SIGNAL_RUN_FIRST,
+                          gobject.TYPE_NONE,
+                          ([])),
+        'angle-changed': (gobject.SIGNAL_RUN_FIRST,
+                          gobject.TYPE_NONE,
+                          ([]))
+    }
+
+    __gproperties__ = {
+        'zoom':    (gobject.TYPE_FLOAT, 
+            'Zoom Factor', 'Factor of zoom', 
+            0, 4, 1, gobject.PARAM_READWRITE),
+        'angle':    (gobject.TYPE_INT,
+            'Angle',    'Angle of rotation',
+            0, 360, 0, gobject.PARAM_READWRITE),
+        'file_location':   (gobject.TYPE_STRING,
+            'File Location', 'Location of the image file',
+            '', gobject.PARAM_READWRITE)
+    }
+
+    def __init__(self):
+        gtk.DrawingArea.__init__(self)
+        self.set_app_paintable(True)
+
+        self.pixbuf = None
+        self.zoom = None
+        self.file_location = None
+        self._temp_pixbuf = None
+        self._image_changed_flag = True
+        self._optimal_zoom_flag = True
+
+        self.angle = 0
+
+
+    def do_get_property(self, property):
+        if property.name == 'zoom':
+            return self.zoom
+        elif property.name == 'angle':
+            return self.angle
+        elif property.name == 'file_location':
+            return self.file_location
+        else:
+            raise AttributeError, 'unknown property %s' % property.name
+
+    def do_set_property(self, property, value):
+        if property.name == 'zoom':
+            self.set_zoom(value)
+        elif property.name == 'angle':
+            self.set_angle(value)
+        elif property.name == 'file_location':
+            self.set_file_location(value)
+        else:
+            raise AttributeError, 'unknown property %s' % property.name
+
+    def calculate_optimal_zoom(self, width = None, height = None, pixbuf = None):
+        # This tries to figure out a best fit model
+        # If the image can fit in, we show it in 1:1, 
+        # in any other case we show it in a fit to screen way
+
+        if pixbuf == None:
+            pixbuf = self.pixbuf
+
+        if width == None or height == None:
+            rect =  self.parent.get_allocation()
+            width = rect.width
+            height = rect.height
+
+        if width < pixbuf.get_width() or height < pixbuf.get_height():
+            # Image is larger than allocated size
+            zoom = min(width/pixbuf.get_width(), height/pixbuf.get_height())
+        else:
+            zoom = 1
+
+        self._optimal_zoom_flag = True
+
+        return zoom - 0.02 #XXX: Hack
+
+    #def do_size_request(self, requisition):
+    #    requisition.width = self.pixbuf.get_width()
+    #    requisition.height = self.pixbuf.get_height()
+
+    def do_expose_event(self, event):
+        ctx = self.window.cairo_create()
+
+        ctx.rectangle(event.area.x, event.area.y, 
+            event.area.width, event.area.height)
+        ctx.clip()
+        self.draw(ctx)
+
+    def draw(self, ctx):
+        if not self.pixbuf:
+            return
+        if self.zoom == None:
+            self.zoom = self.calculate_optimal_zoom()
+        
+        if self._temp_pixbuf == None or self._image_changed_flag == True:
+            width, height = self.rotate()
+            self._temp_pixbuf = self._temp_pixbuf.scale_simple(width, height, gtk.gdk.INTERP_TILES)
+            self._image_changed_flag = False
+
+        rect = self.get_allocation()
+        x = rect.x
+        y = rect.y
+
+        width = self._temp_pixbuf.get_width()
+        height = self._temp_pixbuf.get_height()
+
+        if self.parent:
+            rect = self.parent.get_allocation()
+            if rect.width > width:
+                x = int(((rect.width - x) - width)/2)
+
+            if rect.height > height:
+                y = int(((rect.height - y) - height)/2)
+
+        self.set_size_request(self._temp_pixbuf.get_width(),self._temp_pixbuf.get_height())
+
+        ctx.set_source_pixbuf(self._temp_pixbuf, x, y)
+
+        ctx.paint()
+
+
+    def set_zoom(self, zoom):
+        self._image_changed_flag = True
+        self._optimal_zoom_flag = False
+        self.zoom = zoom
+
+        if self.window:
+            alloc = self.get_allocation()
+            rect = gdk.Rectangle(alloc.x, alloc.y, 
+                alloc.width, alloc.height)
+            self.window.invalidate_rect(rect, True)
+            self.window.process_updates(True)
+
+        self.emit('zoom-changed')
+
+    def set_angle(self, angle):
+        self._image_changed_flag = True
+        self._optimal_zoom_flag = True
+
+        self.angle = angle
+
+        if self.window:
+            alloc = self.get_allocation()
+            rect = gdk.Rectangle(alloc.x, alloc.y,
+                alloc.width, alloc.height)
+            self.window.invalidate_rect(rect, True)
+            self.window.process_updates(True)
+
+        self.emit('angle-changed')
+
+
+
+    def rotate(self):
+        if self.angle == 0:
+            rotate = gtk.gdk.PIXBUF_ROTATE_NONE
+        elif self.angle == 90:
+            rotate = gtk.gdk.PIXBUF_ROTATE_COUNTERCLOCKWISE
+        elif self.angle == 180:
+            rotate = gtk.gdk.PIXBUF_ROTATE_UPSIDEDOWN
+        elif self.angle == 270:
+            rotate = gtk.gdk.PIXBUF_ROTATE_CLOCKWISE
+        elif self.angle == 360:
+            self.angle = 0
+            rotate = gtk.gdk.PIXBUF_ROTATE_NONE
+        else:
+            logging.warning('Got unsupported rotate angle')
+            pass
+            
+        self._temp_pixbuf = self.pixbuf.rotate_simple(rotate)
+        if self._optimal_zoom_flag == True:
+            self.zoom = self.calculate_optimal_zoom(pixbuf = self._temp_pixbuf)
+        
+        width = int(self._temp_pixbuf.get_width()*self.zoom)
+        height = int(self._temp_pixbuf.get_height()*self.zoom)
+
+        return (width, height)
+
+    def zoom_in(self):
+        self.set_zoom(self.zoom + 0.2)
+        if self.zoom > (4):
+            return False
+        else:
+            return True
+
+    def zoom_out(self):
+        self.set_zoom(self.zoom - 0.2)
+        if self.zoom <= 0.2:
+            return False
+        else:
+            return True
+
+    def set_file_location(self, file_location):
+        self.pixbuf = gtk.gdk.pixbuf_new_from_file(file_location)
+        self.file_location = file_location
+        self.zoom = None
+        self._image_changed_flag = True
+
+        if self.window:
+            alloc = self.get_allocation()
+            rect = gdk.Rectangle(alloc.x, alloc.y,
+                alloc.width, alloc.height)
+            self.window.invalidate_rect(rect, True)
+            self.window.process_updates(True)
+
+
+def update(view):
+    #return view.zoom_out()
+    angle = 90 * random.randint(0,4)
+    view.set_angle(angle)
+
+    return True
+
+
+
+if __name__ == '__main__':
+    window = gtk.Window()
+
+    vadj = gtk.Adjustment()
+    hadj = gtk.Adjustment()
+    sw = gtk.ScrolledWindow(hadj, vadj)
+
+    view = ImageViewer()
+
+    view.set_file_location(sys.argv[1])
+
+
+    sw.set_policy(gtk.POLICY_AUTOMATIC, gtk.POLICY_AUTOMATIC)
+
+
+    sw.add_with_viewport(view)
+    window.add(sw)
+
+    window.set_size_request(800,600)
+
+    window.show_all()
+
+    gobject.timeout_add(1000, update, view)
+
+    gtk.main()
+