Integration with other Libraries

NumPy & ImageSurface

Creating an ImageSurface from a NumPy array:
import numpy
import cairo

width, height = 255, 255
data = numpy.ndarray(shape=(height, width), dtype=numpy.uint32)
surface = cairo.ImageSurface.create_for_data(
    data, cairo.FORMAT_ARGB32, width, height)
Creating a NumPy array from an ImageSurface:
import numpy
import cairo

width, height = 255, 255
surface = cairo.ImageSurface(cairo.FORMAT_ARGB32, width, height)
buf = surface.get_data()
data = numpy.ndarray(shape=(height, width),
                     dtype=numpy.uint32,
                     buffer=buf)

Pygame & ImageSurface

Creating a pygame.image from an ImageSurface:
import pygame
import cairo

width, height = 255, 255
surface = cairo.ImageSurface(cairo.FORMAT_ARGB32, width, height)
buf = surface.get_data()
image = pygame.image.frombuffer(buf, (width, height), "ARGB")

Pyglet & ImageSurface as Texture

Creating a pyglet.Texture from an ImageSurface:
import ctypes
import cairo

from pyglet import app, clock, gl, image, window

# create data shared by ImageSurface and Texture
width, height = 400, 400

surface_data = (ctypes.c_ubyte * (width * height * 4))()
surface = cairo.ImageSurface.create_for_data (surface_data, cairo.FORMAT_ARGB32,
width, height, width * 4);
texture = image.Texture.create_for_size(gl.GL_TEXTURE_2D, width, height, gl.GL_RGBA)
Draw pyglet.Texture bound to ImageSurface
window = window.Window(width=width, height=height)

@window.event
def on_draw():
    window.clear()

    # Draw texture backed by ImageSurface
    gl.glEnable(gl.GL_TEXTURE_2D)

    gl.glBindTexture(gl.GL_TEXTURE_2D, texture.id)
    gl.glTexImage2D(gl.GL_TEXTURE_2D, 0, gl.GL_RGBA, width, height, 0, gl.GL_BGRA,
    gl.GL_UNSIGNED_BYTE,
    surface_data)

    gl.glBegin(gl.GL_QUADS)
    gl.glTexCoord2f(0.0, 1.0)
    gl.glVertex2i(0, 0)
    gl.glTexCoord2f(1.0, 1.0)
    gl.glVertex2i(width, 0)
    gl.glTexCoord2f(1.0, 0.0)
    gl.glVertex2i(width, height)
    gl.glTexCoord2f(0.0, 0.0)
    gl.glVertex2i(0, height)
    gl.glEnd()

# call clock.schedule_update here to update the ImageSurface every frame
app.run()

Pillow (PIL) & Cairo

Creating an ImageSurface from a PIL Image:
import cairo
import PIL.Image as Image

def from_pil(im: Image, alpha: float=1.0, format: cairo.Format=cairo.FORMAT_ARGB32) -> cairo.ImageSurface:
    """
    :param im: Pillow Image
    :param alpha: 0..1 alpha to add to non-alpha images
    :param format: Pixel format for output surface
    """
    assert format in (cairo.FORMAT_RGB24, cairo.FORMAT_ARGB32), "Unsupported pixel format: %s" % format
    if 'A' not in im.getbands():
        im.putalpha(int(alpha * 256.))
    arr = bytearray(im.tobytes('raw', 'BGRa'))
    surface = cairo.ImageSurface.create_for_data(arr, format, im.width, im.height)
    return surface


filename = 'test.jpeg'

# Open image to an ARGB32 ImageSurface
im = Image.open(filename)
surface1 = from_pil(im)

# Open image to an RGB24 ImageSurface
im = Image.open(filename)
surface2 = from_pil(im, format=cairo.FORMAT_RGB24)

# Open image to an ARGB32 ImageSurface, 50% opacity
im = Image.open(filename)
surface3 = from_pil(im, alpha=0.5, format=cairo.FORMAT_ARGB32)
Converting an ImageSurface to a PIL Image:
import cairo
import PIL.Image as Image

def to_pil(surface: cairo.ImageSurface) -> Image:
    format = surface.get_format()
    size = (surface.get_width(), surface.get_height())
    stride = surface.get_stride()

    with surface.get_data() as memory:
        if format == cairo.Format.RGB24:
            return Image.frombuffer(
                "RGB", size, memory.tobytes(),
                'raw', "BGRX", stride)
        elif format == cairo.Format.ARGB32:
            return Image.frombuffer(
                "RGBA", size, memory.tobytes(),
                'raw', "BGRa", stride)
        else:
            raise NotImplementedError(repr(format))

# Create an image surface from a PNG file (or any other source)
surface = cairo.ImageSurface.create_from_png("test.png")

# Convert to a PIL Image
im = to_pil(surface)

# Use Pillow to store it as a JPEG
im.save("result.jpg")

Freetype-py & Cairo

See https://github.com/rougier/freetype-py/tree/master/examples for examples. Most of the *-cairo.py examples illustrate conversion from FreeType bitmaps to Cairo surfaces; the two examples, glyph-vector-cairo.py and glyph-vector-2-cairo.py, illustrate conversion from FreeType glyph contours to Cairo paths.

ModernGL & ImageSurface as Texture

Creating a moderngl.Texture from an ImageSurface:
import moderngl
import cairo
ctx = moderngl.create_context(standalone=True)
width, height = 400, 400
surface = cairo.ImageSurface(cairo.FORMAT_ARGB32, width, height)
texture = ctx.texture((width, height), 4, data=surface.get_data())

An example can also be found in the ModernGL project: https://github.com/moderngl/moderngl/blob/master/examples/integration_pycairo.py