python-enable 4.3.0-2 / usr / lib / python2.7 / dist-packages / kiva / ps.py

#------------------------------------------------------------------------------
# Copyright (c) 2005, Enthought, Inc.
# All rights reserved.
#
# This software is provided without warranty under the terms of the BSD
# license included in enthought/LICENSE.txt and may be redistributed only
# under the conditions described in the aforementioned license.  The license
# is also available online at http://www.enthought.com/licenses/BSD.txt
# Thanks for using Enthought open source!
#------------------------------------------------------------------------------
""" Chaco's PostScript (PS/EPSF) backend

    :Copyright:   ActiveState
    :License:     BSD Style
    :Author:      David Ascher (davida@activestate.com)
    :Version:     $Revision: 1.2 $
"""

# Major library imports
import os
import sys
from cStringIO import StringIO
from numpy import arange, ravel, array
import warnings

# Local, relative Kiva imports
import affine
import basecore2d
import constants
from constants import *
import agg

# This backend does not have compiled paths, yet.
CompiledPath = None

try:
    import logging
    import tempfile
    _logfile = os.path.join(tempfile.gettempdir(), "kivaps.log")
    hdlr = logging.FileHandler(_logfile)
    BASIC_FORMAT = "%(levelname)s: %(name)s: %(message)s"
    fmt = logging.Formatter(BASIC_FORMAT)
    hdlr.setFormatter(fmt)
    logging.root.addHandler(hdlr)
    log = logging.getLogger('')
    log.setLevel(logging.INFO)
except ImportError:
    class FakeLogger:
        def debug(self, message):
            print >> sys.stderr, "DEBUG:", message
        def info(self, message):
            print >> sys.stderr, "INFO:", message
        def warn(self, message):
            print >> sys.stderr, "WARN:", message
        def error(self, message):
            print >> sys.stderr, "ERROR:", message
        def critical(self, message):
            print >> sys.stderr, "CRITICAL:", message
    log = FakeLogger()

def _strpoints(points):
    c = StringIO()
    for x,y in points:
        c.write('%3.2f,%3.2f ' % (x,y))
    return c.getvalue()

def _mkstyle(kw):
    return '"' + '; '.join([str(k) + ':' + str(v) for k,v in kw.items()]) +'"'


def default_filter(kw1):
    kw = {}
    for (k,v) in kw1.items():
        if type(v) == type(()):
            if v[0] != v[1]:
                kw[k] = v[0]
        else:
            kw[k] = v
    return kw

line_cap_map = {
    constants.CAP_BUTT: 0,
    constants.CAP_ROUND: 1,
    constants.CAP_SQUARE: 2,
}

line_join_map = {
    constants.JOIN_MITER: 0,
    constants.JOIN_ROUND: 1,
    constants.JOIN_BEVEL: 2,
}

font_map = {'Arial': 'Helvetica'}

import _fontdata

font_map = {'Arial': 'Helvetica'}
try:
    # reportlab supports more fonts
    import reportlab.pdfbase.pdfmetrics as pdfmetrics
    import reportlab.pdfbase._fontdata as _fontdata
    _reportlab_loaded = 1
except ImportError:
    # we support the basic 14
    import pdfmetrics
    import _fontdata
    _reportlab_loaded = 0

font_face_map = {'Arial': 'Helvetica', '': 'Helvetica'}

_clip_counter = 0

fill_stroke_map = {FILL_STROKE: ('fill', 'stroke'),
                    EOF_FILL_STROKE: ('eofill', 'stroke'),
                    FILL: ('fill', None),
                    STROKE: ('stroke', None),
                    EOF_FILL: ('eofill', None)
                   }


class PSGC(basecore2d.GraphicsContextBase):

    def __init__(self, size, *args, **kwargs):
        super(PSGC, self).__init__(size, *args, **kwargs)
        self.size = size
        self._height = size[1]
        self.contents = StringIO()
        self._clipmap = {}
        self.clip_id = None

    def clear(self):
        self.contents = StringIO()

    def width(self):
        return self.size[0]

    def height(self):
        return self.size[1]

    def save(self, filename):
        f = open(filename, 'w')
        ext = os.path.splitext(filename)[1]
        if ext in ('.eps', '.epsf'):
            f.write("%!PS-Adobe-3.0 EPSF-3.0\n")
            f.write('%%%%BoundingBox: 0 0 %d %d\n' % self.size)
            f.write(self.contents.getvalue())
        elif ext == '.ps':
            f.write("%!PS-Adobe-2.0\n")
            f.write(self.contents.getvalue())
        else:
            raise ValueError, "don't know how to write a %s file" % ext

    # Text handling code

    def set_font(self, font):
        self.face_name = font_face_map.get(font.face_name, font.face_name)
        self.font = pdfmetrics.Font(self.face_name, self.face_name, pdfmetrics.defaultEncoding)
        self.font_size = font.size
        self.contents.write("""/%s findfont %3.3f scalefont setfont\n""" % (self.face_name, self.font_size))

    def device_show_text(self, text):
        ttm = self.get_text_matrix()
        ctm = self.get_ctm()  # not device_ctm!!
        m = affine.concat(ctm,ttm)
        if self.state.clipping_path:
            self.contents.write('clipsave\n')
            self.contents.write('%3.3f %3.3f %3.3f %3.3f rectclip\n' % self.state.clipping_path)
        self.contents.write('gsave\n')
        self.device_transform_device_ctm(LOAD_CTM, [m])
        self.contents.write('%3.3f %3.3f moveto\n' % (0,0))
        r,g,b,a = self.state.line_color
        self.contents.write('%1.3f %1.3f %1.3f setrgbcolor\n' % (r,g,b) )
        self.contents.write('(%s) show\n' % text)
        self.contents.write('grestore\n')
        if self.state.clipping_path:
            self.contents.write('cliprestore\n')

    def get_full_text_extent(self, text):
        ascent,descent=_fontdata.ascent_descent[self.face_name]
        descent = (-descent) * self.font_size / 1000.0
        ascent = ascent * self.font_size / 1000.0
        height = ascent + descent
        width = pdfmetrics.stringWidth(text, self.face_name, self.font_size)
        return width, height, descent, height*1.2 # assume leading of 1.2*height

    # actual implementation =)

    def device_draw_image(self, img, rect):
        """
        draw_image(img_gc, rect=(x,y,w,h))

        Draws another gc into this one.  If 'rect' is not provided, then
        the image gc is drawn into this one, rooted at (0,0) and at full
        pixel size.  If 'rect' is provided, then the image is resized
        into the (w,h) given and drawn into this GC at point (x,y).

        img_gc is either a Numeric array (WxHx3 or WxHx4) or a GC from Kiva's
        Agg backend (kiva.agg.GraphicsContextArray).

        Requires the Python Imaging Library (PIL).
        """
        from PIL import Image as PilImage

        if type(img) == type(array([])):
            # Numeric array
            converted_img = agg.GraphicsContextArray(img, pix_format='rgba32')
            format = 'RGBA'
        elif isinstance(img, agg.GraphicsContextArray):
            if img.format().startswith('RGBA'):
                format = 'RGBA'
            elif img.format().startswith('RGB'):
                format = 'RGB'
            else:
                converted_img = img.convert_pixel_format('rgba32', inplace=0)
                format = 'RGBA'
            # Should probably take this into account
            # interp = img.get_image_interpolation()
        else:
            warnings.warn("Cannot render image of type %r into EPS context."
                          % type(img))
            return

        # converted_img now holds an Agg graphics context with the image
        pil_img = PilImage.fromstring(format,
                                      (converted_img.width(),
                                       converted_img.height()),
                                      converted_img.bmp_array.tostring())
        if rect == None:
            rect = (0, 0, img.width(), img.height())

        # PIL PS output doesn't support alpha.
        if format != 'RGB':
            pil_img = pil_img.convert('RGB')

        left, top, width, height = rect
        if width != img.width() or height != img.height():
            # This is not strictly required.
            pil_img = pil_img.resize((int(width), int(height)), PilImage.NEAREST)

        self.contents.write('gsave\n')
        self.contents.write('initmatrix\n')
        m = self.get_ctm()
        self.contents.write('[%.3f %.3f %.3f %.3f %.3f %.3f] concat\n' % \
                            affine.affine_params(m))
        self.contents.write('%.3f %.3f translate\n' % (left, top))
        # Rely on PIL's EpsImagePlugin to do the hard work here.
        pil_img.save(self.contents, 'eps', eps=0)
        self.contents.write('grestore\n')

    def device_transform_device_ctm(self,func,args):
        if func == LOAD_CTM:
            self.contents.write('initmatrix\n')
            func = CONCAT_CTM

        if func == SCALE_CTM:
            sx, sy = args
            self.contents.write('%.3f %.3f scale\n' % (sx, sy))
        elif func == ROTATE_CTM:
            r, = args
            self.contents.write('%.3f rotate\n' % r)
        elif func == TRANSLATE_CTM:
            tx, ty = args
            self.contents.write('%.3f %.3f translate\n' % (tx, ty))
        elif func == CONCAT_CTM:
            m, = args
            self.contents.write('[%.3f %.3f %.3f %.3f %.3f %.3f] concat\n' % \
                                affine.affine_params(m))

    def device_fill_points(self, points, mode):
        if self.state.clipping_path:
            self.contents.write('clipsave\n')
            self.contents.write('%3.3f %3.3f %3.3f %3.3f rectclip\n' % self.state.clipping_path)
        linecap = line_cap_map[self.state.line_cap]
        linejoin = line_join_map[self.state.line_join]
        dasharray = self._dasharray()
        if dasharray:
            self.contents.write('%s 0 setdash\n' % dasharray)
        self.contents.write('%3.3f setlinewidth\n' % self.state.line_width)
        self.contents.write('%d setlinecap\n' % linecap)
        self.contents.write('%d setlinejoin\n' % linejoin)
        self.contents.write('newpath\n')
        x,y = points[0]
        self.contents.write('    %3.3f %3.3f moveto\n' % (x,y))
        for (x,y) in points[1:]:
            self.contents.write('    %3.3f %3.3f lineto\n' % (x,y))

        first_pass, second_pass = fill_stroke_map[mode]

        if second_pass:
            if first_pass in ('fill', 'eofill'):
                r,g,b,a = self.state.fill_color
                self.contents.write('%1.3f %1.3f %1.3f setrgbcolor\n' % (r,g,b) )
            else:
                r,g,b,a = self.state.line_color
                self.contents.write('%1.3f %1.3f %1.3f setrgbcolor\n' % (r,g,b) )

            self.contents.write('gsave %s grestore %s\n' % (first_pass, second_pass))
        else:
            if first_pass in ('fill', 'eofill'):
                r,g,b,a = self.state.fill_color
                self.contents.write('%1.3f %1.3f %1.3f setrgbcolor\n' % (r,g,b) )
            else:
                r,g,b,a = self.state.line_color
                self.contents.write('%1.3f %1.3f %1.3f setrgbcolor\n' % (r,g,b) )
            self.contents.write(first_pass + '\n')
        if self.state.clipping_path:
            self.contents.write('cliprestore\n')

    def device_stroke_points(self, points, mode):
        # handled by device_fill_points
        pass

    def device_set_clipping_path(self, x, y, width, height):
        pass

    def device_destroy_clipping_path(self):
        pass

    # utility routines

    def _color(self, color):
        r,g,b,a = color
        return '#%02x%02x%02x' % (r*255,g*255,b*255)

    def _dasharray(self):
        dasharray = ''
        for x in self.state.line_dash:
            if type(x) == type(arange(3)):  # why is this so hard?
                x = ravel(x)[0]
            dasharray += ' ' + '%3.2f' % x
        if not dasharray or dasharray == " 0.00 0.00":
            return '[]'
        return '[ ' + dasharray + ' ]'

    # noops which seem to be needed

    def device_update_line_state(self):
        pass

    def device_update_fill_state(self):
        pass