Added Invert Color Effect to Paint Activity (OLPC #2495)

Signed-off-by: Ayush Goyal <ayush@seeta.in>

3 files changed, 459 insertions, 22 deletions

diff --git a/Area.py b/Area.py
index a0e82d0..a4f744f 100644
--- a/Area.py
+++ b/Area.py
@@ -69,10 +69,12 @@ import os
 import tempfile
 import math
 import pango
+import numpy
 from fill import *
 from Desenho import Desenho
 from urlparse import urlparse
 
+
 ##Tools and events manipulation are handle with this class.
 
 TARGET_URI = 0
@@ -80,7 +82,6 @@ TARGET_URI = 0
 
 class Area(gtk.DrawingArea):
 
-
     __gsignals__ = {
         'undo': (gobject.SIGNAL_ACTION, gobject.TYPE_NONE, ([])),
         'redo': (gobject.SIGNAL_ACTION, gobject.TYPE_NONE, ([])),
@@ -227,7 +228,7 @@ class Area(gtk.DrawingArea):
         self.gc = win.new_gc()
         self.gc_eraser = win.new_gc()
         colormap = self.get_colormap()
-        self.white = colormap.alloc_color('#ffffff', True, True) # white
+        self.white = colormap.alloc_color('#ffffff', True, True)  # white
         self.black = colormap.alloc_color('#000000', True, True)  # black
 
         self.gc_eraser.set_foreground(self.white)
@@ -555,7 +556,7 @@ class Area(gtk.DrawingArea):
                     self.selmove = True
                     self.sel_get_out = False
                     self.emit('select')
-                elif self.sel_get_out: #get out of the func selection
+                elif self.sel_get_out:  # get out of the func selection
                     self.getout()
                     try:
                         del(self.d.pixbuf_resize)
@@ -648,7 +649,7 @@ class Area(gtk.DrawingArea):
         if self.undo_times > 0:
             self.undo_times -= 1
             self.redo_times += 1
-            try: #to not try paint someting wrong
+            try:  # to not try paint someting wrong
                 self.pixmap.draw_drawable(self.gc,
                     self.undo_list[self.undo_times], 0, 0, 0, 0, width, height)
             except:
@@ -663,7 +664,7 @@ class Area(gtk.DrawingArea):
 
         #special case for func polygon
         if self.tool['name'] == 'freeform':
-                self.polygon_start = True #start the polygon again
+                self.polygon_start = True  # start the polygon again
 
         self.emit('undo')
 
@@ -680,7 +681,7 @@ class Area(gtk.DrawingArea):
             self.redo_times -= 1
             self.undo_times += 1
 
-            try: #to not try paint someting wrong
+            try:  # to not try paint someting wrong
                 self.pixmap.draw_drawable(self.gc,
                     self.undo_list[self.undo_times], 0, 0, 0, 0,
                     width, height)
@@ -705,11 +706,11 @@ class Area(gtk.DrawingArea):
         if self.undo_surf:
             self.undo_times += 1
 
-        self.undo_list.append(None)#alloc memory
+        self.undo_list.append(None)  # alloc memory
         self.undo_list[self.undo_times] = gtk.gdk.Pixmap(widget.window,
-            width, height, -1) #define type
+            width, height, -1)  # define type
         self.undo_list[self.undo_times].draw_drawable(self.gc, self.pixmap,
-            0, 0, 0, 0, width, height) #copy workarea
+            0, 0, 0, 0, width, height)  # copy workarea
         self.undo_times += 1
         self.redo_times = 0
         self.first_undo = True
@@ -915,6 +916,56 @@ class Area(gtk.DrawingArea):
         if not self.selmove:
             self.enableUndo(widget)
 
+    def invert_colors(self, widget):
+        """Apply invert effect.
+
+            @param  self -- the Area object (GtkDrawingArea)
+            @param  widget -- the Area object (GtkDrawingArea)
+
+        """
+
+        width, height = self.window.get_size()
+
+        if self.selmove:
+            size = self.pixmap_sel.get_size()
+            pix = gtk.gdk.Pixbuf(gtk.gdk.COLORSPACE_RGB, False, 8,
+                size[0], size[1])
+            pix.get_from_drawable(self.pixmap_sel,
+                gtk.gdk.colormap_get_system(), 0, 0, 0, 0, size[0], size[1])
+        else:
+            pix = gtk.gdk.Pixbuf(gtk.gdk.COLORSPACE_RGB, False, 8,
+                width, height)
+            pix.get_from_drawable(self.pixmap, gtk.gdk.colormap_get_system(),
+                0, 0, 0, 0, width, height)
+
+        pix_manip2 = pix.get_pixels_array()
+        pix_manip = numpy.ones(pix_manip2.shape, dtype=numpy.uint8) * 255
+        pix_manip2 = pix_manip - pix_manip2
+        pix = gtk.gdk.pixbuf_new_from_array(pix_manip2, gtk.gdk.COLORSPACE_RGB,
+                                            8)
+
+        if self.selmove:
+            self.pixmap_sel.draw_pixbuf(self.gc, pix, 0, 0, 0, 0,
+                size[0], size[1], dither=gtk.gdk.RGB_DITHER_NORMAL,
+                x_dither=0, y_dither=0)
+
+            self.pixmap_temp.draw_drawable(self.gc, self.pixmap, 0, 0, 0, 0,
+                width, height)
+            self.pixmap_temp.draw_drawable(self.gc, self.pixmap_sel,
+                0, 0, self.orig_x, self.orig_y, size[0], size[1])
+            self.pixmap_temp.draw_rectangle(self.gc_selection, False,
+                self.orig_x, self.orig_y, size[0], size[1])
+            self.pixmap_temp.draw_rectangle(self.gc_selection1, False,
+                self.orig_x - 1, self.orig_y - 1, size[0] + 2, size[1] + 2)
+
+        else:
+            self.pixmap.draw_pixbuf(self.gc, pix, 0, 0, 0, 0, width, height,
+                dither=gtk.gdk.RGB_DITHER_NORMAL, x_dither=0, y_dither=0)
+
+        self.queue_draw()
+        if not self.selmove:
+            self.enableUndo(widget)
+
     def _pixbuf2Image(self, pb):
         """change a pixbuf to RGB image
 
@@ -1274,7 +1325,7 @@ class Area(gtk.DrawingArea):
             self.orig_x = 0
             self.orig_y = 0
             self.pixmap_temp.draw_rectangle(self.gc_selection, False,
-                0, 0, width-1, height-1)
+                0, 0, width - 1, height - 1)
             self.selmove = True
             self.sel_get_out = False
             self.emit('select')
diff --git a/icons/invert-colors.svg b/icons/invert-colors.svg
new file mode 100644
index 0000000..373ca70
--- /dev/null
+++ b/icons/invert-colors.svg
@@ -0,0 +1,387 @@
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+<svg
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+   xmlns:dc="http://purl.org/dc/elements/1.1/"
+   xmlns:cc="http://creativecommons.org/ns#"
+   xmlns:rdf="http://www.w3.org/1999/02/22-rdf-syntax-ns#"
+   xmlns:svg="http://www.w3.org/2000/svg"
+   xmlns="http://www.w3.org/2000/svg"
+   xmlns:xlink="http://www.w3.org/1999/xlink"
+   xmlns:sodipodi="http://sodipodi.sourceforge.net/DTD/sodipodi-0.dtd"
+   xmlns:inkscape="http://www.inkscape.org/namespaces/inkscape"
+   enable-background="new 0 0 55 55"
+   height="55px"
+   version="1.1"
+   viewBox="0 0 55 55"
+   width="55px"
+   x="0px"
+   xml:space="preserve"
+   y="0px"
+   id="svg2"
+   inkscape:version="0.48.0 r9654"
+   sodipodi:docname="invert-colors.svg"><metadata
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\ No newline at end of file
diff --git a/toolbox.py b/toolbox.py
index 53e05fa..1ff4e6f 100644
--- a/toolbox.py
+++ b/toolbox.py
@@ -430,7 +430,6 @@ class ToolsToolbar(gtk.Toolbar):
         except:
             logging.debug('Could not create palette for tool selection area')
 
-
         # New connect method
         # Using dictionnaries to control tool's properties
         self._tool_pencil.connect('clicked', self.set_tool, self._TOOL_PENCIL)
@@ -564,8 +563,6 @@ class ToolsToolbar(gtk.Toolbar):
 
         #setting cursor: Moved to Area
 
-
-
 #     def _on_fill_checkbutton_map(self, checkbutton, data=None):
 #         """
 #         Update checkbutton condition to agree with Area.Area object;
@@ -809,7 +806,6 @@ class ShapesToolbar(gtk.Toolbar):
         except:
             logging.debug('Could not create palette for Shape Triangle')
 
-
         self._shape_arrow.connect('clicked', self.set_tool, self._SHAPE_ARROW)
         self._shape_ellipse.connect('clicked', self.set_tool,
             self._SHAPE_ELLIPSE)
@@ -1031,7 +1027,6 @@ class TextToolbar(gtk.Toolbar):
         separator.set_draw(True)
         self.insert(separator, -1)
 
-
         """
         #FIXME: this button is not connected to the right callback
         self._bold = ToggleToolButton('format-text-bold')
@@ -1249,6 +1244,7 @@ class ImageToolbar(gtk.Toolbar):
 class EffectsToolbar(gtk.Toolbar):
 
     _EFFECT_GRAYSCALE = 'grayscale'
+    _INVERT_COLOR = 'invert-colors'
     # Rainbow acts as a tool in Area, and it has to be described as a dict
     _EFFECT_RAINBOW = {'name': 'rainbow',
                         'line size': 10,
@@ -1272,6 +1268,11 @@ class EffectsToolbar(gtk.Toolbar):
         self.insert(self._effect_rainbow, -1)
         self._configure_palette(self._effect_rainbow, self._EFFECT_RAINBOW)
 
+        self._invert_colors = ToolButton('invert-colors')
+        self.insert(self._invert_colors, -1)
+        self._invert_colors.show()
+        self._invert_colors.set_tooltip(_('Invert Colors'))
+
         separator = gtk.SeparatorToolItem()
         self.insert(separator, -1)
 
@@ -1284,16 +1285,11 @@ class EffectsToolbar(gtk.Toolbar):
             'effect-black-and-white')
         self._black_and_white.set_tooltip(_('Black and White'))
 
-        self._invert_colors = ToolButton('invert_colors')
-        self.insert(self._invert_colors, -1)
-        self._invert_colors.show()
-        self._invert_colors.connect('clicked', test_connect, activity,
-            'invert-colors')
-        self._invert_colors.set_tooltip(_('Invert Colors'))
-
         """
+
         self._effect_grayscale.connect('clicked', self.grayscale)
         self._effect_rainbow.connect('clicked', self.rainbow)
+        self._invert_colors.connect('clicked', self.invert_colors)
 
     ##Make the colors be in grayscale
     def grayscale(self, widget):
@@ -1303,6 +1299,9 @@ class EffectsToolbar(gtk.Toolbar):
     def rainbow(self, widget):
         self._activity.area.set_tool(self._EFFECT_RAINBOW)
 
+    def invert_colors(self, widget):
+        self._activity.area.invert_colors(widget)
+
         # setting cursor: moved to Area
 
     def _configure_palette(self, button, tool=None):