与其他库集成¶
numpy和imagesurface¶
- 从numpy数组创建ImageSurface:
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)
- 从ImageSurface创建numpy数组:
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和ImageSurface¶
- 从ImageSurface创建pygame.image:
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和ImageSurface作为纹理¶
- 创建皮格莱特。纹理从图像表面:
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)
- 绘制绑定到ImageSurface的Pyglet.Texture
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()
枕头(PIL)和 Cairo¶
- 从PIL图像创建ImageSurface:
import PIL.Image as Image def from_pil(im, alpha=1.0, format=cairo.FORMAT_ARGB32): """ :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)
弗里特派和 Cairo¶
示例请参见https://github.com/rougier/freetype-py/tree/master/examples。大部分 *-cairo.py
示例说明从freetype位图到cairo曲面的转换;这两个示例, glyph-vector-cairo.py
和 glyph-vector-2-cairo.py
,演示从freetype glyph轮廓到cairo路径的转换。
现代图像表面作为纹理(&I)¶
- 创建现代纹理从图像表面:
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())
在ModernGL项目中也可以找到一个例子:https://github.com/moderngl/moderngl/blob/master/examples/integration_pycairo.py