"""
An agg http://antigrain.com/ backend
Features that are implemented
* capstyles and join styles
* dashes
* linewidth
* lines, rectangles, ellipses
* clipping to a rectangle
* output to RGBA and PNG
* alpha blending
* DPI scaling properly - everything scales properly (dashes, linewidths, etc)
* draw polygon
* freetype2 w/ ft2font
TODO:
* allow save to file handle
* allow load from png
* integrate screen dpi w/ ppi and text
INSTALLING
REQUIREMENTs
python2.2+
Numeric 22+
agg2 (see below)
freetype 2
libpng
libz
Install AGG2 (cut and paste below into xterm should work)
wget http://www.antigrain.com/agg2.tar.gz
tar xvfz agg2.tar.gz
cd agg2
make
(Optional) if you want to make the examples:
cd examples/X11
make
Installing backend_agg
Edit setup.py: change aggsrc to point to the agg2 src tree and
replace if 0: with if 1: in the backend_agg section
Then just do the usual thing: python setup.py build
Please let me know if you encounter build problems, and tell me
platform, gcc version, etc... Currently the paths in setupext.py
assume as linux like filesystem (eg X11 include dir, location of
libttf, etcc) so you may need to tweak these
Using agg backend
python somefile.py -dAgg
or
import matplotlib
matplotlib.use('Agg')
"""
from __future__ import division
import os, sys
import matplotlib
from matplotlib import verbose, rcParams
from matplotlib.numerix import array, Float, zeros, transpose
from matplotlib._image import fromarray
from matplotlib._pylab_helpers import Gcf
from matplotlib.backend_bases import RendererBase,\
GraphicsContextBase, FigureManagerBase, FigureCanvasBase
from matplotlib.cbook import enumerate, is_string_like, exception_to_str
from matplotlib.figure import Figure
from matplotlib.font_manager import fontManager
from matplotlib.ft2font import FT2Font
from matplotlib.mathtext import math_parse_s_ft2font
from matplotlib.transforms import lbwh_to_bbox
from matplotlib.numerix.mlab import fliplr
import matplotlib.numerix
if matplotlib.numerix.which[0] == "numarray":
from _na_backend_agg import RendererAgg as _RendererAgg
elif matplotlib.numerix.which[0] == "numeric":
from _nc_backend_agg import RendererAgg as _RendererAgg
else:
from _ns_backend_agg import RendererAgg as _RendererAgg
backend_version = 'v2.2'
_fontd = {} # a map from fname to font instances
class RendererAgg(RendererBase):
"""
The renderer handles all the drawing primitives using a graphics
context instance that controls the colors/styles
"""
debug=1
texd = {} # a cache of tex image rasters
def __init__(self, width, height, dpi):
if __debug__: verbose.report('RendererAgg.__init__', 'debug-annoying')
RendererBase.__init__(self)
self.dpi = dpi
self.width = width
self.height = height
if __debug__: verbose.report('RendererAgg.__init__ width=%s, \
height=%s'%(width, height), 'debug-annoying')
self._renderer = _RendererAgg(int(width), int(height), dpi.get(),
debug=False)
if __debug__: verbose.report('RendererAgg.__init__ _RendererAgg done',
'debug-annoying')
self.draw_polygon = self._renderer.draw_polygon
self.draw_rectangle = self._renderer.draw_rectangle
self.draw_path = self._renderer.draw_path
self.draw_lines = self._renderer.draw_lines
self.draw_markers = self._renderer.draw_markers
self.draw_image = self._renderer.draw_image
self.draw_line_collection = self._renderer.draw_line_collection
self.draw_quad_mesh = self._renderer.draw_quad_mesh
self.draw_poly_collection = self._renderer.draw_poly_collection
self.draw_regpoly_collection = self._renderer.draw_regpoly_collection
self.copy_from_bbox = self._renderer.copy_from_bbox
self.restore_region = self._renderer.restore_region
self.bbox = lbwh_to_bbox(0,0, self.width, self.height)
if __debug__: verbose.report('RendererAgg.__init__ done',
'debug-annoying')
def draw_arc(self, gcEdge, rgbFace, x, y, width, height, angle1, angle2, rotation):
"""
Draw an arc centered at x,y with width and height and angles
from 0.0 to 360.0
If rgbFace is not None, fill the rectangle with that color. gcEdge
is a GraphicsContext instance
Currently, I'm only supporting ellipses, ie angle args are
ignored
"""
if __debug__: verbose.report('RendererAgg.draw_arc', 'debug-annoying')
self._renderer.draw_ellipse(
gcEdge, rgbFace, x, y, width/2, height/2, rotation) # ellipse takes radius
def draw_line(self, gc, x1, y1, x2, y2):
"""
x and y are equal length arrays, draw lines connecting each
point in x, y
"""
if __debug__: verbose.report('RendererAgg.draw_line', 'debug-annoying')
x = array([x1,x2], typecode=Float)
y = array([y1,y2], typecode=Float)
self._renderer.draw_lines(gc, x, y)
def draw_point(self, gc, x, y):
"""
Draw a single point at x,y
"""
if __debug__: verbose.report('RendererAgg.draw_point', 'debug-annoying')
rgbFace = gc.get_rgb()
self._renderer.draw_ellipse(
gc, rgbFace, x, y, 0.5, 0.5)
def draw_mathtext(self, gc, x, y, s, prop, angle):
"""
Draw the math text using matplotlib.mathtext
"""
if __debug__: verbose.report('RendererAgg.draw_mathtext',
'debug-annoying')
size = prop.get_size_in_points()
width, height, fonts = math_parse_s_ft2font(
s, self.dpi.get(), size, angle)
if angle == 90:
width, height = height, width
for font in fonts:
if angle == 90:
font.horiz_image_to_vert_image() # <-- Rotate
self._renderer.draw_text( font, int(x)-width, int(y)-height, gc)
else:
self._renderer.draw_text( font, int(x), int(y)-height, gc)
if 0:
self._renderer.draw_rectangle(gc, None,
int(x),
self.height-int(y),
width, height)
def draw_text(self, gc, x, y, s, prop, angle, ismath):
"""
Render the text
"""
if __debug__: verbose.report('RendererAgg.draw_text', 'debug-annoying')
if ismath:
return self.draw_mathtext(gc, x, y, s, prop, angle)
font = self._get_agg_font(prop)
if font is None: return None
if len(s)==1 and ord(s)>127:
font.load_char(ord(s))
else:
font.set_text(s, angle)
font.draw_glyphs_to_bitmap()
#print x, y, int(x), int(y)
self._renderer.draw_text(font, int(x), int(y), gc)
def get_text_width_height(self, s, prop, ismath, rgb=(0,0,0)):
"""
get the width and height in display coords of the string s
with FontPropertry prop
# passing rgb is a little hack to make cacheing in the
# texmanager more efficient. It is not meant to be used
# outside the backend
"""
if ismath=='TeX':
# todo: handle props
size = prop.get_size_in_points()
texmanager = self.get_texmanager()
Z = texmanager.get_rgba(s, size, self.dpi.get(), rgb)
m,n,tmp = Z.shape
return n,m
if ismath:
width, height, fonts = math_parse_s_ft2font(
s, self.dpi.get(), prop.get_size_in_points())
return width, height
font = self._get_agg_font(prop)
font.set_text(s, 0.0) # the width and height of unrotated string
w, h = font.get_width_height()
w /= 64.0 # convert from subpixels
h /= 64.0
return w, h
def draw_tex(self, gc, x, y, s, prop, angle):
# todo, handle props, angle, origins
rgb = gc.get_rgb()
size = prop.get_size_in_points()
dpi = self.dpi.get()
flip = angle==90
w,h = self.get_text_width_height(s, prop, 'TeX', rgb)
if flip:
w,h = h,w
x -= w
texmanager = self.get_texmanager()
key = s, size, dpi, rgb, angle, texmanager.get_font_config()
im = self.texd.get(key)
if im is None:
Z = texmanager.get_rgba(s, size, dpi, rgb)
if flip:
r = Z[:,:,0]
g = Z[:,:,1]
b = Z[:,:,2]
a = Z[:,:,3]
m,n,tmp = Z.shape
def func(x):
return transpose(fliplr(x))
Z = zeros((n,m,4), typecode=Float)
Z[:,:,0] = func(r)
Z[:,:,1] = func(g)
Z[:,:,2] = func(b)
Z[:,:,3] = func(a)
im = fromarray(Z, 1)
im.flipud_out()
self.texd[key] = im
cliprect = gc.get_clip_rectangle()
if cliprect is None: bbox = None
else: bbox = lbwh_to_bbox(*cliprect)
self.draw_image(x, self.height-y, im, bbox)
def get_canvas_width_height(self):
'return the canvas width and height in display coords'
return self.width, self.height
def _get_agg_font(self, prop):
"""
Get the font for text instance t, cacheing for efficiency
"""
if __debug__: verbose.report('RendererAgg._get_agg_font',
'debug-annoying')
key = hash(prop)
font = _fontd.get(key)
if font is None:
fname = fontManager.findfont(prop)
font = FT2Font(str(fname))
_fontd[key] = font
font.clear()
size = prop.get_size_in_points()
font.set_size(size, self.dpi.get())
return font
def points_to_pixels(self, points):
"""
convert point measures to pixes using dpi and the pixels per
inch of the display
"""
if __debug__: verbose.report('RendererAgg.points_to_pixels',
'debug-annoying')
return points*self.dpi.get()/72.0
def tostring_rgb(self):
if __debug__: verbose.report('RendererAgg.tostring_rgb',
'debug-annoying')
return self._renderer.tostring_rgb()
def tostring_argb(self):
if __debug__: verbose.report('RendererAgg.tostring_argb',
'debug-annoying')
return self._renderer.tostring_argb()
def buffer_rgba(self,x,y):
if __debug__: verbose.report('RendererAgg.buffer_rgba',
'debug-annoying')
return self._renderer.buffer_rgba(x,y)
def clear(self):
self._renderer.clear()
def new_figure_manager(num, *args, **kwargs):
"""
Create a new figure manager instance
"""
if __debug__: verbose.report('backend_agg.new_figure_manager',
'debug-annoying')
FigureClass = kwargs.pop('FigureClass', Figure)
thisFig = FigureClass(*args, **kwargs)
canvas = FigureCanvasAgg(thisFig)
manager = FigureManagerBase(canvas, num)
return manager
class FigureCanvasAgg(FigureCanvasBase):
"""
The canvas the figure renders into. Calls the draw and print fig
methods, creates the renderers, etc...
Public attribute
figure - A Figure instance
"""
def copy_from_bbox(self, bbox):
renderer = self.get_renderer()
return renderer.copy_from_bbox(bbox)
def restore_region(self, region):
renderer = self.get_renderer()
return renderer.restore_region(region)
def draw(self):
"""
Draw the figure using the renderer
"""
if __debug__: verbose.report('FigureCanvasAgg.draw', 'debug-annoying')
renderer = self.get_renderer()
self.figure.draw(renderer)
def get_renderer(self):
l,b,w,h = self.figure.bbox.get_bounds()
key = w, h, self.figure.dpi.get()
try: self._lastKey, self.renderer
except AttributeError: need_new_renderer = True
else: need_new_renderer = (self._lastKey != key)
if need_new_renderer:
self.renderer = RendererAgg(w, h, self.figure.dpi)
self._lastKey = key
return self.renderer
def tostring_rgb(self):
if __debug__: verbose.report('FigureCanvasAgg.tostring_rgb',
'debug-annoying')
return self.renderer.tostring_rgb()
def tostring_argb(self):
if __debug__: verbose.report('FigureCanvasAgg.tostring_argb',
'debug-annoying')
return self.renderer.tostring_argb()
def buffer_rgba(self,x,y):
if __debug__: verbose.report('FigureCanvasAgg.buffer_rgba',
'debug-annoying')
return self.renderer.buffer_rgba(x,y)
def print_figure(self, filename, dpi=None, facecolor='w', edgecolor='w',
orientation='portrait', **kwargs):
"""
Render the figure to hardcopy. Set the figure patch face and
edge colors. This is useful because some of the GUIs have a
gray figure face color background and you'll probably want to
override this on hardcopy
If the extension matches PNG, write a PNG file
If the extension matches BMP or RAW, write an RGBA bitmap file
If filename is a fileobject, write png to file object (thus
you can, for example, write the png to stdout
"""
if __debug__: verbose.report('FigureCanvasAgg.print_figure',
'debug-annoying')
if dpi is None: dpi = matplotlib.rcParams['savefig.dpi']
# store the orig figure dpi, color and size information so we
# can restore them later. For image creation alone, this is
# not important since after the print the figure is done. But
# backend_agg may be used as a renderer for a GUI figure, and
# restoring figure props will be important in that case.
# TODO: move most of this functionality into backend_bases
origDPI = self.figure.dpi.get()
origfacecolor = self.figure.get_facecolor()
origedgecolor = self.figure.get_edgecolor()
self.figure.dpi.set(dpi)
self.figure.set_facecolor(facecolor)
self.figure.set_edgecolor(edgecolor)
# render the printed figure
self.draw()
if not is_string_like(filename):
# assume png and write to fileobject
self.renderer._renderer.write_png(filename)
#pass
else:
# take a look at the extension and choose the print handler
basename, ext = os.path.splitext(filename)
if not len(ext):
ext = '.png'
filename += ext
ext = ext.lower()
if (ext.find('rgb')>=0 or
ext.find('raw')>=0 or
ext.find('bmp')>=0 ):
# agg doesn't handle unicode yet
self.renderer._renderer.write_rgba(str(filename))
elif ext.find('png')>=0:
# agg doesn't handle unicode yet
self.renderer._renderer.write_png(str(filename))
#pass
elif ext.find('svg')>=0:
from backend_svg import FigureCanvasSVG
svg = self.switch_backends(FigureCanvasSVG)
svg.print_figure(filename, dpi, facecolor, edgecolor,
orientation, **kwargs)
elif ext.find('ps')>=0 or ext.find('ep')>=0:
from backend_ps import FigureCanvasPS # lazy import
ps = self.switch_backends(FigureCanvasPS)
ps.print_figure(filename, dpi, facecolor, edgecolor,
orientation, **kwargs)
elif ext.find('pdf')>=0:
from backend_pdf import FigureCanvasPdf
pdf = self.switch_backends(FigureCanvasPdf)
pdf.print_figure(filename, dpi, facecolor, edgecolor,
orientation, **kwargs)
else:
raise IOError('Do not know know to handle extension *%s' % ext)
# restore the original figure properties
self.figure.dpi.set(origDPI)
self.figure.set_facecolor(origfacecolor)
self.figure.set_edgecolor(origedgecolor)
self.figure.set_canvas(self)
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