def pick_color(self, x, y, size=3):
"""Picks the rendered colour at a particular point.
:param int x: X coord of pixel to pick (widget/device coords)
:param int y: Y coord of pixel to pick (widget/device coords)
:param int size: Size of the sampling square.
:returns: The colour sampled.
:rtype: lib.color.UIColor
This method operates by rendering part of the document using the
current settings, then averaging the colour values of the pixels
within the sampling square.
"""
# TODO: the ability to turn *off* this kind of "sample merged".
# Ref: https://github.com/mypaint/mypaint/issues/333
# Make a square surface for the sample.
size = max(1, int(size))
surf = cairo.ImageSurface(cairo.FORMAT_ARGB32, size, size)
cr = cairo.Context(surf)
cr.set_source_rgb(0, 0, 0)
cr.paint()
# Ensure the rendering of the area around (x, y) writes into the
# sample square.
r = int(size/2)
cr.translate(-int(x)+r, -int(y)+r)
# Paint checkerboard if we won't be rendering an opaque background
model = self.doc
render_is_opaque = model and model.layer_stack.get_render_is_opaque()
if (not render_is_opaque) and self._draw_real_alpha_checks:
cr.set_source(self._real_alpha_check_pattern)
cr.paint()
if not model:
return lib.color.RGBColor(0, 1, 1)
# Render just what we need.
transformation, surface, sparse, mipmap_level, clip_rect = \
self._render_prepare(cr)
self._render_execute(
cr,
transformation,
surface,
sparse,
mipmap_level,
clip_rect,
filter = None,
)
surf.flush()
# Extract a pixbuf, then an average color.
#surf.write_to_png("/tmp/grab.png")
pixbuf = gdk.pixbuf_get_from_surface(surf, 0, 0, size, size)
color = lib.color.UIColor.new_from_pixbuf_average(pixbuf)
return color
def image_surface_to_pixbuf(surf):
if gtk2compat.USE_GTK3:
w = surf.get_width()
h = surf.get_height()
return gdk.pixbuf_get_from_surface(surf, 0, 0, w, h)
# GTK2.
# Ugly PNG-based fudge to work around cairo.ImageSurface.get_data()
# returning packed BGRA or ARGB pixels depending on endianness.
png_dp = StringIO()
surf.write_to_png(png_dp)
pixbuf_loader = gdk.PixbufLoader()
pixbuf_loader.write(png_dp.getvalue())
pixbuf_loader.close()
return pixbuf_loader.get_pixbuf()
def image_surface_to_pixbuf(surf):
if gtk2compat.USE_GTK3:
w = surf.get_width()
h = surf.get_height()
return gdk.pixbuf_get_from_surface(surf, 0, 0, w, h)
# GTK2.
# Ugly PNG-based fudge to work around cairo.ImageSurface.get_data()
# returning packed BGRA or ARGB pixels depending on endianness.
png_dp = StringIO()
surf.write_to_png(png_dp)
pixbuf_loader = gdk.PixbufLoader()
pixbuf_loader.write(png_dp.getvalue())
pixbuf_loader.close()
return pixbuf_loader.get_pixbuf()