def create_surface(drawable, visualtype, width=None, height=None):
"""
create a cairo surface for *drawable*.
:Parameters:
`drawable`
`visualtype` : ooxcb.xproto.Visualtype
most likely the result of `screen.get_root_visual_type()`
`width`
`height`
The dimensions of the surface. If one of those arguments
is None, it is retrieved from the drawable's geometry.
"""
if (width is None or height is None):
geom = drawable.get_geometry().reply()
if width is None:
width = geom.width
if height is None:
height = geom.height
return cairo.cairo_xcb_surface_create(drawable.conn,
drawable,
visualtype,
width, height)
def set_root(conn, screen_info, style, func=None):
root = screen_info.root
geom = root.get_geometry().reply()
pixmap = xproto.Pixmap.create(
conn,
root,
geom.width, geom.height,
screen_info.root_depth
)
surface = cairo.cairo_xcb_surface_create(
conn,
pixmap,
screen_info.get_root_visual_type(),
geom.width, geom.height,
)
root.change_attributes(back_pixmap=pixmap)
cr = cairo.cairo_create(surface)
if func is None:
func = yahiko_render
func(cr, style, geom.width, geom.height)
root.clear_area(0, 0, geom.width, geom.height)
conn.flush()
visualtype = screen.get_root_visual_type()
width = 640
height = 480
running = True
with conn.bunch():
win = xproto.Window.create_toplevel_on_screen(conn, screen,
width=width, height=height,
back_pixel=screen.white_pixel,
event_mask=xproto.EventMask.Exposure | xproto.EventMask.ButtonPress
)
win.map()
# create a surface for this window
surface = cairo.cairo_xcb_surface_create(conn, win,
visualtype,
width, height)
# and a cairo context
cr = cairo.cairo_create(surface)
cairo.cairo_set_operator(cr, cairo.CAIRO_OPERATOR_SOURCE)
cairo.cairo_set_source_surface(cr, surface, 0, 0)
cairo.cairo_set_source_rgba(cr, 255, 0, 0, 0)
@win.event
def on_expose(event):
# paint a red rectangle when an expose event occurs
cairo.cairo_set_source_rgb(cr, 255, 0, 0)
cairo.cairo_rectangle(cr, 100, 100, 300, 300)
cairo.cairo_fill(cr)
# don't forget to flush!
import sys
sys.path.append('..')
import ooxcb
from ooxcb.protocol import xproto
from ooxcb.contrib import cairo
conn = ooxcb.connect()
screen = conn.setup.roots[conn.pref_screen]
root = screen.root
surface = cairo.cairo_xcb_surface_create(conn, root,
screen.get_root_visual_type(),
screen.width_in_pixels,
screen.height_in_pixels)
cairo.cairo_surface_write_to_png(surface, "screenshot.png")
conn.disconnect()
