syntrax.py 文件源码

def cairo_text_bbox(text, font_params, scale=1.0):
  surf = cairo.ImageSurface(cairo.FORMAT_ARGB32, 8, 8)
  ctx = cairo.Context(surf)

  # The scaling must match the final context.
  # If not there can be a mismatch between the computed extents here
  # and those generated for the final render.
  ctx.scale(scale, scale)

  font = cairo_font(font_params)

  if use_pygobject:
    layout = pangocairo.create_layout(ctx)
    pctx = layout.get_context()
    fo = cairo.FontOptions()
    fo.set_antialias(cairo.ANTIALIAS_SUBPIXEL)
    pangocairo.context_set_font_options(pctx, fo)
    layout.set_font_description(font)
    layout.set_text(text, len(text))
    re = layout.get_pixel_extents()[1]
    extents = (re.x, re.y, re.x + re.width, re.y + re.height)

  else: # pyGtk
    pctx = pangocairo.CairoContext(ctx)
    pctx.set_antialias(cairo.ANTIALIAS_SUBPIXEL)
    layout = pctx.create_layout()
    layout.set_font_description(font)
    layout.set_text(text)

    #print('@@ EXTENTS:', layout.get_pixel_extents()[1])
    extents = layout.get_pixel_extents()[1]
  w = extents[2] - extents[0]
  h = extents[3] - extents[1]
  x0 = - w // 2.0
  y0 = - h // 2.0
  return [x0,y0, x0+w,y0+h]