I should have also mentioned that the new signature is document in
backend_bases in the _draw_markers method
def _draw_markers(self, gc, path, rgbFace, x, y, trans):
"""
This method is currently underscore hidden because the
draw_markers method is being used as a sentinel for newstyle
backend drawing
path - a matplotlib.agg.path_storage instance
Draw the marker specified in path with graphics context gc at
each of the locations in arrays x and y. trans is a
matplotlib.transforms.Transformation instance used to
transform x and y to display coords. It consists of an
optional nonlinear component and an affine. You can access
these two components as
if transform.need_nonlinear():
x,y = transform.nonlinear_only_numerix(x, y)
# the a,b,c,d,tx,ty affine which transforms x and y
vec6 = transform.as_vec6_val()
...backend dependent affine...
"""
pass