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jdh2358jdh2358
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added array and png helper funcs to mathtext
svn path=/trunk/matplotlib/; revision=5490
1 parent 8c44ac7 commit aac292b

7 files changed

Lines changed: 157 additions & 9 deletions

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‎CHANGELOG‎

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2008-06-12 Added some helper functions to the mathtext parser to
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return bitmap arrays or write pngs to make it easier to use
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mathtext outside the context of an mpl figure. modified
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the mathpng sphinxext to use the mathtext png save
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functionality
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2008-06-11 Use matplotlib.mathtext to render math expressions in
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online docs - MGD
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‎doc/sphinxext/mathpng.py‎

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@@ -92,16 +92,19 @@ def latex2png(latex, name):
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os.system('dvipng -bgTransparent -Ttight --noghostscript -l10 ' +
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'-o %s math.dvi > /dev/null' % name)
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from matplotlib import rcParams
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from matplotlib.mathtext import MathTextParser
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rcParams['mathtext.fontset'] = 'cm'
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mathtext_parser = MathTextParser("Bitmap")
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# This uses mathtext to render the expression
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def latex2png(latex, filename):
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from matplotlib import rcParams
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from matplotlib import _png
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from matplotlib.mathtext import MathTextParser
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rcParams['mathtext.fontset'] = 'cm'
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mathtext_parser = MathTextParser("Bitmap")
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ftimage = mathtext_parser.parse("$%s$" % latex, 120)
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_png.write_png(ftimage.as_rgba_str(), ftimage.get_width(),
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ftimage.get_height(), filename)
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if os.path.exists(filename):
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return
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mathtext_parser.to_png(filename, "$%s$" % latex, dpi=120)
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# LaTeX to HTML translation stuff:
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def latex2html(node, source):

‎examples/api/mathtext_asarray.py‎

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@@ -0,0 +1,19 @@
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"""
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Load a mathtext image as numpy array
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"""
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import numpy as np
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import matplotlib.mathtext as mathtext
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import matplotlib.pyplot as plt
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parser = mathtext.MathTextParser("Bitmap")
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parser.to_png('test2.png', r'$\left[\left\lfloor\frac{5}{\frac{\left(3\right)}{4}} y\right)\right]$', color='green', fontsize=14, dpi=100)
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rgba = parser.to_rgba(r'IQ: $\sigma_i=15$', color='blue', fontsize=20, dpi=200)
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fig = plt.figure()
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fig.figimage(rgba.astype(float)/255., 100, 100)
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plt.show()

‎lib/matplotlib/mathtext.py‎

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@@ -180,7 +180,7 @@
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from warnings import warn
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from numpy import inf, isinf
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import numpy as np
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from matplotlib.pyparsing import Combine, Group, Optional, Forward, \
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Literal, OneOrMore, ZeroOrMore, ParseException, Empty, \
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ParseResults, Suppress, oneOf, StringEnd, ParseFatalException, \
@@ -197,6 +197,10 @@
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latex_to_standard, tex2uni, latex_to_cmex, stix_virtual_fonts
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from matplotlib import get_data_path, rcParams
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import matplotlib.colors as mcolors
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import matplotlib._png as _png
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####################
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@@ -2724,3 +2728,74 @@ def parse(self, s, dpi = 72, prop = None):
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font_output.mathtext_backend = None
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return result
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def to_mask(self, texstr, dpi=120, fontsize=14):
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"""
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return an NxM uint8 alpha ubyte mask array of rasterized tex
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''texstr''
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A valid mathtext string, eg r'IQ: $\sigma_i=15$'
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''dpi''
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The dots-per-inch to render the text
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''fontsize''
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The font size in points
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"""
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assert(self._output=="bitmap")
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prop = FontProperties(size=fontsize)
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ftimage = self.parse(texstr, dpi=dpi, prop=prop)
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x = ftimage.as_array()
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return x
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def to_rgba(self, texstr, color='black', dpi=120, fontsize=14):
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"""
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return an NxMx4 RGBA array of ubyte rasterized tex
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''texstr''
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A valid mathtext string, eg r'IQ: $\sigma_i=15$'
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''color''
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A valid matplotlib color argument
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''dpi''
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The dots-per-inch to render the text
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''fontsize''
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The font size in points
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"""
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x = self.to_mask(texstr, dpi=dpi, fontsize=fontsize)
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r, g, b = mcolors.colorConverter.to_rgb(color)
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RGBA = np.zeros((x.shape[0], x.shape[1], 4), dtype=np.uint8)
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RGBA[:,:,0] = int(255*r)
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RGBA[:,:,1] = int(255*g)
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RGBA[:,:,2] = int(255*b)
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RGBA[:,:,3] = x
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return RGBA
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def to_png(self, filename, texstr, color='black', dpi=120, fontsize=14):
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"""
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''filename''
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A writable filename or fileobject
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''texstr''
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A valid mathtext string, eg r'IQ: $\sigma_i=15$'
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''color''
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A valid matplotlib color argument
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''dpi''
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The dots-per-inch to render the text
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''fontsize''
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The font size in points
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"""
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rgba = self.to_rgba(texstr, color=color, dpi=dpi, fontsize=fontsize)
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numrows, numcols, tmp = rgba.shape
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return _png.write_png(rgba.tostring(), numcols, numrows, filename)
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‎setupext.py‎

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@@ -589,6 +589,7 @@ def add_agg_flags(module):
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def add_ft2font_flags(module):
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'Add the module flags to ft2font extension'
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add_numpy_flags(module)
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if not get_pkgconfig(module, 'freetype2'):
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module.libraries.extend(['freetype', 'z'])
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add_base_flags(module)

‎src/ft2font.cpp‎

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@@ -2,6 +2,9 @@
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#include "mplutils.h"
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#include <sstream>
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#define PY_ARRAY_TYPES_PREFIX NumPy
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#include "numpy/arrayobject.h"
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#define FIXED_MAJOR(val) (*((short *) &val+1))
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#define FIXED_MINOR(val) (*((short *) &val+0))
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@@ -251,6 +254,41 @@ FT2Image::py_as_str(const Py::Tuple & args) {
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);
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}
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char FT2Image::as_array__doc__[] =
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"x = image.as_array()\n"
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"\n"
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"Return the image buffer as a width x height numpy array of ubyte \n"
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"\n"
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;
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Py::Object
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FT2Image::py_as_array(const Py::Tuple & args) {
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_VERBOSE("FT2Image::as_array");
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args.verify_length(0);
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int dimensions[2];
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dimensions[0] = get_height(); //numrows
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dimensions[1] = get_width(); //numcols
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PyArrayObject *A = (PyArrayObject *) PyArray_SimpleNewFromData(2, dimensions, PyArray_UBYTE, _buffer);
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/*
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PyArrayObject *A = (PyArrayObject *) PyArray_FromDims(2, dimensions, PyArray_UBYTE);
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unsigned char *src = _buffer;
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unsigned char *src_end = src + (dimensions[0] * dimensions[1]);
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unsigned char *dst = (unsigned char *)A->data;
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while (src != src_end) {
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*dst++ = *src++;
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}
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*/
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return Py::asObject((PyObject*)A);
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}
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void FT2Image::makeRgbCopy() {
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if (!_isDirty)
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return;
@@ -1697,6 +1735,8 @@ FT2Image::init_type() {
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FT2Image::draw_rect__doc__);
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add_varargs_method("draw_rect_filled", &FT2Image::py_draw_rect_filled,
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FT2Image::draw_rect_filled__doc__);
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add_varargs_method("as_array", &FT2Image::py_as_array,
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FT2Image::as_array__doc__);
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add_varargs_method("as_str", &FT2Image::py_as_str,
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FT2Image::as_str__doc__);
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add_varargs_method("as_rgb_str", &FT2Image::py_as_rgb_str,
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initft2font(void)
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{
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static ft2font_module* ft2font = new ft2font_module;
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import_array();
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Py::Dict d = ft2font->moduleDictionary();
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d["SCALABLE"] = Py::Int(FT_FACE_FLAG_SCALABLE);
@@ -1885,5 +1926,6 @@ initft2font(void)
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}
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ft2font_module::~ft2font_module() {
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FT_Done_FreeType( _ft2Library );
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}

‎src/ft2font.h‎

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@@ -45,6 +45,8 @@ class FT2Image : public Py::PythonExtension<FT2Image> {
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Py::Object py_draw_rect(const Py::Tuple & args);
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static char draw_rect_filled__doc__ [];
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Py::Object py_draw_rect_filled(const Py::Tuple & args);
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static char as_array__doc__ [];
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Py::Object py_as_array(const Py::Tuple & args);
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static char as_str__doc__ [];
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Py::Object py_as_str(const Py::Tuple & args);
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static char as_rgb_str__doc__ [];

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