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The following snippet uses Python's ctypes module to load a font file using FreeType and create a cairo font face from it, using the cairo-ft API that is not part of pycairo yet. The resulting cairo font face however can be used normally with pycairo.
import ctypes
import cairo
_initialized = False
def create_cairo_font_face_for_file (filename, faceindex=0, loadoptions=0):
global _initialized
global _freetype_so
global _cairo_so
global _ft_lib
global _surface
CAIRO_STATUS_SUCCESS = 0
FT_Err_Ok = 0
if not _initialized:
# find shared objects
_freetype_so = ctypes.CDLL ("libfreetype.so.6")
_cairo_so = ctypes.CDLL ("libcairo.so.2")
# initialize freetype
_ft_lib = ctypes.c_void_p ()
if FT_Err_Ok != _freetype_so.FT_Init_FreeType (ctypes.byref (_ft_lib)):
raise "Error initialising FreeType library."
class PycairoContext(ctypes.Structure):
_fields_ = [("PyObject_HEAD", ctypes.c_byte * object.__basicsize__),
("ctx", ctypes.c_void_p),
("base", ctypes.c_void_p)]
_surface = cairo.ImageSurface (cairo.FORMAT_A8, 0, 0)
_initialized = True
# create freetype face
ft_face = ctypes.c_void_p()
cairo_ctx = cairo.Context (_surface)
cairo_t = PycairoContext.from_address(id(cairo_ctx)).ctx
_cairo_so.cairo_ft_font_face_create_for_ft_face.restype = ctypes.c_void_p
if FT_Err_Ok != _freetype_so.FT_New_Face (_ft_lib, filename, faceindex, ctypes.byref(ft_face)):
raise "Error creating FreeType font face for " + filename
# create cairo font face for freetype face
cr_face = _cairo_so.cairo_ft_font_face_create_for_ft_face (ft_face, loadoptions)
if CAIRO_STATUS_SUCCESS != _cairo_so.cairo_font_face_status (cr_face):
raise "Error creating cairo font face for " + filename
_cairo_so.cairo_set_font_face (cairo_t, cr_face)
if CAIRO_STATUS_SUCCESS != _cairo_so.cairo_status (cairo_t):
raise "Error creating cairo font face for " + filename
face = cairo_ctx.get_font_face ()
return face
if __name__ == '__main__':
face = create_cairo_font_face_for_file ("/usr/share/fonts/dejavu-lgc/DejaVuLGCSerif.ttf", 0)
surface = cairo.ImageSurface(cairo.FORMAT_ARGB32, 128, 128)
ctx = cairo.Context(surface)
ctx.set_font_face(face)
ctx.set_font_size(30)
ctx.move_to(0, 44)
ctx.show_text("Hello,")
ctx.move_to(30, 74)
ctx.show_text("world!")
del ctx
surface.write_to_png("hello.png")