def _ContextFromDC(dc):
"""
Creates and returns a Cairo context object using the wxDC as the
surface. (Only window, client, paint and memory DC's are allowed
at this time.)
"""
if not isinstance(dc, wx.WindowDC) and not isinstance(dc, wx.MemoryDC):
raise TypeError(
"Only window and memory DC's are supported at this time.")
if 'wxMac' in wx.PlatformInfo:
width, height = dc.GetSize()
# use the CGContextRef of the DC to make the cairo surface
cgc = dc.GetHandle()
assert cgc is not None, "Unable to get CGContext from DC."
cgref = voidp(cgc)
surfaceptr = voidp(surface_create(cgref, width, height))
# create a cairo context for that surface
ctxptr = voidp(cairo_create(surfaceptr))
# Turn it into a pycairo context object
ctx = pycairoAPI.Context_FromContext(ctxptr, pycairoAPI.Context_Type,
None)
# The context keeps its own reference to the surface
cairoLib.cairo_surface_destroy(surfaceptr)
elif 'wxMSW' in wx.PlatformInfo:
# This one is easy, just fetch the HDC and use PyCairo to make
# the surface and context.
hdc = dc.GetHandle()
# Ensure the pointer value is clampped into the range of a C signed long
hdc = ctypes.c_long(hdc)
surface = cairo.Win32Surface(hdc.value)
ctx = cairo.Context(surface)
elif 'wxGTK' in wx.PlatformInfo:
if 'gtk3' in wx.PlatformInfo:
# With wxGTK3, GetHandle() returns a cairo context directly
ctxptr = voidp(dc.GetHandle())
# pyCairo will try to destroy it so we need to increase ref count
cairoLib.cairo_reference(ctxptr)
else:
# Get the GdkDrawable from the dc
drawable = voidp(dc.GetHandle())
# Call a GDK API to create a cairo context
ctxptr = gdkLib.gdk_cairo_create(drawable)
# Turn it into a pycairo context object
ctx = pycairoAPI.Context_FromContext(ctxptr, pycairoAPI.Context_Type,
None)
else:
raise NotImplementedError("Help me, I'm lost...")
return ctx
def ContextFromDC(dc):
"""
Creates and returns a Cairo context object using the wxDC as the
surface. (Only window, client, paint and memory DC's are allowed
at this time.)
"""
if not isinstance(dc, wx.WindowDC) and not isinstance(dc, wx.MemoryDC):
raise TypeError, "Only window and memory DC's are supported at this time."
if 'wxMac' in wx.PlatformInfo:
width, height = dc.GetSize()
# use the CGContextRef of the DC to make the cairo surface
cgc = dc.GetCGContext()
assert cgc is not None, "Unable to get CGContext from DC."
cgref = voidp(cgc)
surfaceptr = voidp(
cairoLib.cairo_quartz_surface_create_for_cg_context(
cgref, width, height))
# create a cairo context for that surface
ctxptr = cairoLib.cairo_create(surfaceptr)
# Turn it into a pycairo context object
ctx = pycairoAPI.Context_FromContext(ctxptr, pycairoAPI.Context_Type,
None)
# The context keeps its own reference to the surface
cairoLib.cairo_surface_destroy(surfaceptr)
elif 'wxMSW' in wx.PlatformInfo:
# This one is easy, just fetch the HDC and use PyCairo to make
# the surface and context.
hdc = dc.GetHDC()
surface = cairo.Win32Surface(hdc)
ctx = cairo.Context(surface)
elif 'wxGTK' in wx.PlatformInfo:
gdkLib = _findGDKLib()
# Get the GdkDrawable from the dc
drawable = voidp(dc.GetGdkDrawable())
# Call a GDK API to create a cairo context
gdkLib.gdk_cairo_create.restype = ctypes.c_void_p
ctxptr = gdkLib.gdk_cairo_create(drawable)
# Turn it into a pycairo context object
ctx = pycairoAPI.Context_FromContext(ctxptr, pycairoAPI.Context_Type,
None)
else:
raise NotImplementedError, "Help me, I'm lost..."
return ctx
def __new__(cls, *args, **kwargs):
import cairo
return cairo.Win32Surface(*args, **kwargs)
