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@trappedinspacetime
Created May 22, 2022 10:57
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all in all pycairo example
#!/usr/bin/python3
################################################################################
##3456789 123456789 123456789 123456789 123456789 123456789 123456789 123456789
##
## Info:
## python-port of cairo-based countdown effect
##
## Run:
## chmod +x countdown.py
## ./countdown.py
##
## Copyright 2014 Mirco Mueller
##
## Author:
## Mirco "MacSlow" Mueller <macslow@gmail.com>
##
## This program is free software: you can redistribute it and/or modify it
## under the terms of the GNU General Public License version 3, as published
## by the Free Software Foundation.
##
## This program is distributed in the hope that it will be useful, but
## WITHOUT ANY WARRANTY; without even the implied warranties of
## MERCHANTABILITY, SATISFACTORY QUALITY, 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, see <http://www.gnu.org/licenses/>.
##
################################################################################
from ctypes import *
import time
import math
import cairo
from gi.repository import GLib, Gdk, Gtk, Pango, PangoCairo
HEIGHT_FRACTION = 2.5
COUNTDOWN_STEPS = 5
FPS = 24
LIBPIXMAN_NAME = "libpixman-1.so"
PIXMAN_FILTER_CONVOLUTION = 5
PIXMAN_OP_SRC = 1
PIXMAN_a8r8g8b8 = 0x20028888
class Countdown:
def setupPixman (self, name):
libpixman = cdll.LoadLibrary (name)
self.pixman_image_create_bits = libpixman.pixman_image_create_bits
self.pixman_image_set_filter = libpixman.pixman_image_set_filter
self.pixman_image_composite = libpixman.pixman_image_composite
self.pixman_image_unref = libpixman.pixman_image_unref
def drawNumber (self, cr, width, height, number):
# create pango desc/layout
if (self.layout == None):
self.layout = PangoCairo.create_layout (cr)
self.desc = Pango.font_description_from_string ("Ubuntu Mono")
self.desc.set_absolute_size (0.75 * height * Pango.SCALE)
self.desc.set_weight (Pango.Weight.NORMAL)
self.desc.set_style (Pango.Style.NORMAL)
self.layout.set_font_description (self.desc)
# print and layout string (pango-wise)
self.layout.set_text (str (number), -1)
# determine center position for number
rects = self.layout.get_extents ()
x = width / 2 - rects[0].x / Pango.SCALE - rects[0].width / Pango.SCALE / 2;
y = height / 2 - rects[0].y / Pango.SCALE - rects[0].height / Pango.SCALE / 2;
# draw text
cr.move_to (x, y)
PangoCairo.layout_path (cr, self.layout)
cr.set_operator (cairo.OPERATOR_SOURCE)
cr.set_source_rgb (0.0, 0.0, 0.0)
cr.fill ()
def createGaussianBlurKerne1D (self, radius, sigma):
scale2 = 2.0 * sigma * sigma
scale1 = 1.0 / (math.pi * scale2)
size = 2 * radius + 1;
n_params = size
tmp = (c_double * n_params)()
tmpSum = 0.0
i = 0
# caluclate gaussian kernel in floating point format
for x in range (-radius, radius + 1):
u = x * x
tmp[i] = scale1 * math.exp (-u / scale2)
tmpSum += tmp[i]
i += 1
# normalize gaussian kernel and convert to fixed point format
params = (c_int32 * (n_params + 2))()
params[0] = size << 16
params[1] = 1 << 16
for i in range (n_params):
params[2 + i] = int ((tmp[i] / tmpSum) * 65536.0)
n_params += 2
return params, n_params
def blurSurface (self, surface, data, radius, sigma):
width = surface.get_width ()
height = surface.get_height ()
stride = surface.get_stride ()
format = surface.get_format ()
# create pixman image for cairo image surface
src = self.pixman_image_create_bits (PIXMAN_a8r8g8b8, width, height, data, stride)
# attach gaussian kernel to pixman image
params, n_params = self.createGaussianBlurKerne1D (radius, sigma)
self.pixman_image_set_filter (src, PIXMAN_FILTER_CONVOLUTION, params, n_params)
# render blured image to new pixman image
pass1Data = (c_uint32 * stride * height)()
pass1 = self.pixman_image_create_bits (PIXMAN_a8r8g8b8, width, height, pass1Data, stride)
self.pixman_image_composite (PIXMAN_OP_SRC, src, None, pass1, 0, 0, 0, 0, 0, 0, width, height)
self.pixman_image_unref (src)
# flip the 1D kernel
tmp = params[0]
params[0] = params[1]
params[1] = tmp
self.pixman_image_set_filter (pass1, PIXMAN_FILTER_CONVOLUTION, params, n_params)
pass2Data = (c_ubyte * stride * height)()
pass2 = self.pixman_image_create_bits (PIXMAN_a8r8g8b8, width, height, pass2Data, stride)
self.pixman_image_composite (PIXMAN_OP_SRC, pass1, None, pass2, 0, 0, 0, 0, 0, 0, width, height)
self.pixman_image_unref (pass1)
# create new cairo image for blured pixman image
surface = cairo.ImageSurface.create_for_data (pass2Data, format, width, height, stride)
self.pixman_image_unref (pass2)
return surface
def createDropShadow (self, width, height, blurRadius):
stride = 4 * width
format = cairo.FORMAT_ARGB32
data = (c_uint32 * stride * height)()
surface = cairo.ImageSurface.create_for_data (data, format, width, height)
cr = cairo.Context (surface)
# clear context
cr.scale (width, height)
cr.set_operator (cairo.OPERATOR_CLEAR)
cr.paint ()
# drop-shadow
cr.set_operator (cairo.OPERATOR_SOURCE)
cr.set_source_rgba (0.35, 0.35, 0.35, 0.8)
cr.move_to (0.5, 0.5)
cr.arc (0.5, 0.5, 0.4125, 0.0, math.pi / 180.0 * 360.0)
cr.close_path ()
cr.fill ()
# blur surface
blurredSurface = self.blurSurface (surface, data, 10, 3.0)
return blurredSurface
def render (self, cr, width, height, angle, number):
# clear context
cr.set_operator (cairo.OPERATOR_CLEAR)
cr.paint ()
cr.set_operator (cairo.OPERATOR_SOURCE)
# "drop-shadow" with blurrrrrrr!!!
if (self.dropShadow):
cr.set_source_surface (self.dropShadow, 0.0, 0.0)
cr.paint ()
cr.save ()
cr.set_operator (cairo.OPERATOR_SOURCE)
cr.scale (width, height)
# draw "tinted" area
cr.set_source_rgba (0.65, 0.65, 0.65, 0.9)
cr.move_to (0.5, 0.5)
fillRadian = -math.pi / 180.0 * (angle + 90.0);
cr.arc (0.5, 0.5, 0.40375, math.pi / 180.0 * 270.0, fillRadian)
cr.close_path ()
cr.fill ()
# draw black "grid"
cr.set_line_join (cairo.LINE_JOIN_ROUND)
cr.set_line_cap (cairo.LINE_CAP_BUTT)
cr.set_line_width (0.0025)
cr.set_source_rgb (0.0, 0.0, 0.0)
cr.move_to (0.5 - 0.40375, 0.5)
cr.rel_line_to (2.0 * 0.40375, 0.0)
cr.move_to (0.5, 0.5 - 0.40375)
cr.rel_line_to (0.0, 2.0 * 0.40375)
cr.stroke ()
# draw two thick black lines
strokeRadian = math.pi / 180.0 * (angle - 180.0)
x = math.sin (strokeRadian) * 0.40375
y = math.cos (strokeRadian) * 0.40375
cr.set_line_width (0.0125)
cr.move_to (0.5, 0.5 - 0.40375)
cr.line_to (0.5, 0.5)
cr.rel_line_to (x, y)
cr.stroke ()
# draw two white circles
cr.set_source_rgb (1.0, 1.0, 1.0)
cr.set_line_width (0.0085)
cr.arc (0.5, 0.5, 0.4, 0.0, 2 * math.pi)
cr.stroke ()
cr.arc (0.5, 0.5, 0.35, 0.0, 2 * math.pi)
cr.stroke ()
cr.restore ()
self.drawNumber (cr, width, height, number)
def onDraw (self, widget, cr, number):
secondsf = time.time () - self.starttime
seconds = math.trunc (secondsf) % number
angle = (math.trunc (secondsf) - secondsf) * 360.0
self.render (cr, widget.get_allocated_width (), widget.get_allocated_height (), angle, number - seconds)
if (number - seconds == 1):
widget.set_opacity (1.0 + (math.trunc (secondsf) - secondsf))
else:
widget.set_opacity (1.0)
return True
def onScreenChanged (self, widget, oldScreen):
screen = widget.get_screen ()
visual = screen.get_rgba_visual ()
if (visual == None):
visual = screen.get_system_visual ()
widget.set_visual (visual)
def onDelete (self, widget, event):
Gtk.main_quit ()
return False
def onTimeout (self, widget):
widget.queue_draw ()
return True
def __init__(self):
# create gtk-window for drawing
self.window = Gtk.Window (Gtk.WindowType.TOPLEVEL)
self.window.set_app_paintable (True)
self.window.set_decorated (False)
self.window.set_title ("cairo-countdown")
self.window.set_keep_above (True)
self.window.set_focus_on_map (False)
self.window.set_accept_focus (False)
self.window.set_skip_pager_hint (True)
self.window.set_skip_taskbar_hint (True)
# make window click-through, this needs pycairo 1.10.0 for python3
# to work
rect = cairo.RectangleInt (0, 0, 1, 1)
region = cairo.Region (rect)
if (not region.is_empty ()):
self.window.input_shape_combine_region (None)
self.window.input_shape_combine_region (region)
# make sure that gtk-window opens with a RGBA-visual
self.onScreenChanged (self.window, None)
self.window.realize ()
self.window.set_type_hint (Gdk.WindowTypeHint.DOCK)
transparent = Gdk.RGBA (0.0, 0.0, 0.0, 0.0)
gdkwindow = self.window.get_window ()
gdkwindow.set_background_rgba (transparent)
# center the gtk-window on the screen
screen = self.window.get_screen ()
monitor = screen.get_monitor_at_window (gdkwindow)
geo = screen.get_monitor_geometry (monitor)
size = geo.height / HEIGHT_FRACTION
self.window.set_size_request (size, size)
self.window.set_position (Gtk.WindowPosition.CENTER)
# now it's time to show it
self.window.show_all ()
# setup libpixman via ctypes
self.setupPixman (LIBPIXMAN_NAME)
# start timer and timeout
self.timeoutId = GLib.timeout_add (1000 / FPS, self.onTimeout, self.window)
self.layout = None
self.desc = None
self.starttime = time.time ()
self.dropShadow = self.createDropShadow (int (size), int (size), 10)
# hook up signal-callbacks
self.window.connect ("screen-changed", self.onScreenChanged)
self.window.connect ("draw", self.onDraw, COUNTDOWN_STEPS)
self.window.connect ("delete-event", self.onDelete)
countdown = Countdown ()
Gtk.main ()
self.layout.unref ()
self.desc.free ()
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