Paste this code into a text editor, make it executable and run it. When you choose a color with the eyedropper, the x and y coordinates will appear at the top.
Edit: Wrote code to add a zoom window. To have it grab pixels outside of the window click the button (not the eyedropper). Click the button again to stop grabbing the pointer. Haven’t figured out how to draw a crosshair with cairo, but you can probably use as is. I left some cairo code in there in case someone can tell me why my rectangle doesn’t draw…
#!/usr/bin/python
from gi.repository import Gtk,Gdk, GdkPixbuf
import cairo
class picker(Gtk.Window):
def __init__(self):
Gtk.Window.__init__(self)
self.connect('delete-event', Gtk.main_quit)
self.connect('motion-notify-event', self.motion_cb)
self.connect('button-press-event',self.button_press)
box=Gtk.Box(orientation=Gtk.Orientation.HORIZONTAL)
#Setup area for coordinates and zoom window
coordbox=Gtk.Box(orientation=Gtk.Orientation.VERTICAL)
self.xcoor=Gtk.Label("x: ")
coordbox.pack_start(self.xcoor, True, False, 1)
self.ycoor=Gtk.Label("y: ")
coordbox.pack_start(self.ycoor, True, False, 1)
self.zoomwin=Gtk.Image()
#Trying to draw on Gtk.Image with cairo for crosshairs... Not working
self.zoomwin.connect('draw', self.draw)
self.zoomwin.set_app_paintable(True)
coordbox.pack_start(self.zoomwin,True,True,1)
self.buttongo=Gtk.Button("Pick Color")
self.buttongo.connect('clicked',self.gobutton_activate)
coordbox.pack_start(self.buttongo,True,True,1)
box.pack_start(coordbox, True, False, 5)
#Put in color wheel for tweaking color
self.cp=Gtk.ColorSelection()
self.cp.connect('color-changed', self.on_color_changed)
box.pack_start(self.cp, True, True, 5)
self.add(box)
self.show_all()
#Set some initial parameters
self.w,self.h=10,10 #Size of zoomed image in pixels
self.count=0
self.window=self.get_window()
#set initial zoom image
self.zoomwin.set_from_pixbuf(self.get_image().scale_simple(240,240,GdkPixbuf.InterpType.TILES))
self.grabbing=False
def on_color_changed(self,widget=None, data=None):
#Print out x,y to widgets
display=Gdk.Display.get_default()
(screen,x,y,modifier)=display.get_pointer()
self.xcoor.set_text("x: %i" %x)
self.ycoor.set_text("y: %i" %y)
def get_image(self,w=None,h=None):
#Get a pixbuff image under pointer
if w==None: w=self.w
if h==None: h=self.h
display=Gdk.Display.get_default()
(screen,self.x,self.y,modifier)=display.get_pointer()
window=Gdk.get_default_root_window()
screenshot = Gdk.pixbuf_get_from_window(window,
self.x-int(w/2), self.y-int(h/2), int(w), int(h))
return screenshot
def motion_cb(self, widget, data):
#What to do while mouse pointer is moving
#DONT capture every event! Causes too much backup
if self.count==5:
self.pixbuf=self.get_image().scale_simple(240,240,GdkPixbuf.InterpType.TILES)
self.zoomwin.set_from_pixbuf(self.pixbuf)
self.zoomwin.queue_draw()
self.count=0
self.count+=1
def grab_start(self):
#Grab control of pointer outside of window
self.grabbing = True
Gdk.pointer_grab(self.window,
True, #allow passage of pointer events to children
Gdk.EventMask.POINTER_MOTION_MASK | Gdk.EventMask.BUTTON_PRESS_MASK | Gdk.EventMask.BUTTON_RELEASE_MASK,
None,
None,# could put a custom cursor here
0L)
def button_press(self,widget,data):
#capture color under the pointer and set the color selection
cenpx=self.get_image(1,1)
color=tuple(map(ord, cenpx.get_pixels()[:3]))
col=Gdk.RGBA(float(color[0])/256.,float(color[1])/256.,float(color[2])/256.)
self.cp.set_current_rgba(col)
def grab_stop(self):
#Stop Grabbing the pointer
Gdk.pointer_ungrab(0)
self.grabbing=False
def gobutton_activate(self, widget, data=None):
#Button control
if self.grabbing==False:
self.grab_start()
widget.set_label("Stop Picking")
else:
self.grab_stop()
widget.set_label("Pick Color")
def draw(self, widget, cr):
#this gets called, but nothing is drawn that I can see...
cr.set_operator(cairo.OPERATOR_SOURCE)
cr.set_source_rgba(1,1,1,1)
w = self.w
h = self.h
cr.set_source_rgba(1,1,1,1)
cr.set_line_width(10)
cr.rectangle(w/2-1,h/2-1,w/2+1,h/2+1)
cr.stroke()
cr.set_operator(cairo.OPERATOR_OVER)
if __name__=="__main__":
win=picker()
Gtk.main()