PythonCAD/Interface/Gtk/gtktext.py

   1 #
   2 # Copyright (c) 2003, 2004, 2006, 2007 Art Haas
   3 #
   4 # This file is part of PythonCAD.
   5 #
   6 # PythonCAD is free software; you can redistribute it and/or modify
   7 # it under the terms of the GNU General Public License as published by
   8 # the Free Software Foundation; either version 2 of the License, or
   9 # (at your option) any later version.
  10 #
  11 # PythonCAD is distributed in the hope that it will be useful,
  12 # but WITHOUT ANY WARRANTY; without even the implied warranty of
  13 # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14 # GNU General Public License for more details.
  15 #
  16 # You should have received a copy of the GNU General Public License
  17 # along with PythonCAD; if not, write to the Free Software
  18 # Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  19 #
  20 #
  21 # GTK interface code for dealing with text entities
  22 #
  23
  24 import pygtk
  25 pygtk.require('2.0')
  26 import gtk
  27 import pango
  28
  29 from PythonCAD.Generic.text import TextStyle, TextBlock
  30
  31 def set_textblock_bounds(gtkimage, tblock):
  32     # print "set_textblock_bounds() ..."
  33     _text = tblock.getText()
  34     if len(_text) == 0:
  35         tblock.setBounds(0, 0)
  36         tblock.setFontScale(1/float(pango.SCALE))
  37         return
  38     _family = tblock.getFamily()
  39     _style = tblock.getStyle()
  40     _weight = tblock.getWeight()
  41     _size = tblock.getSize()
  42     _da = gtkimage.getDA()
  43     _upp = gtkimage.getUnitsPerPixel()
  44     #
  45     # initial test layout ...
  46     #
  47     _layout = _da.create_pango_layout(_text)
  48     _fd = pango.FontDescription()
  49     _fd.set_family(_family)
  50     _fd.set_style(_style)
  51     _fd.set_weight(_weight)
  52     #
  53     # use an 18-point font as first size guess
  54     #
  55     _fs = 18
  56     _fd.set_size(pango.SCALE * _fs)
  57     _layout.set_font_description(_fd)
  58     _nlines = _layout.get_line_count()
  59     #
  60     # the pixel height of the TextBlock
  61     #
  62     _th = _nlines * _size
  63     # print "TextBlock height: %g" % _th
  64     _ph = _th/_upp
  65     _iph = int(_ph)
  66     if _iph/_nlines < 3: # tiny text - use the 18-point values for boundary
  67         _w, _h = _layout.get_size()
  68         _tw = (_w * _th)/float(_h)
  69         tblock.setBounds(_tw, _th)
  70         tblock.setFontScale(1/float(pango.SCALE))
  71         _layout = None
  72         return
  73     # print "TextBlock pixel height: %g [%d]" % (_ph, _iph)
  74     _w, _h = _layout.get_pixel_size()
  75     # print "first layout: w: %d; h: %d" % (_w, _h)
  76     _i = 0
  77     if _h != _iph:
  78         #
  79         # loop until the layout pixel height equals the "correct" pixel height
  80         #
  81         _diff = abs(_h - _iph)
  82         _ofs = _fs
  83         _fs = (_fs * _ph)/float(_h)
  84         # print "adjusted font size: %g" % (_fs)
  85         while True:
  86             _layout = _da.create_pango_layout(_text)
  87             _fd = pango.FontDescription()
  88             _fd.set_family(_family)
  89             _fd.set_style(_style)
  90             _fd.set_weight(_weight)
  91             _fd.set_size(int(pango.SCALE * _fs))
  92             _layout.set_font_description(_fd)
  93             _w, _h = _layout.get_pixel_size()
  94             # print "adjusted layout: w: %d; h: %d" % (_w, _h)
  95             #
  96             # tests to bail out
  97             #
  98             # all the inexact comparisons and iteration max
  99             # count text are arbitrary ...
 100             #
 101             if _h == _iph:
 102                 # print "exact match"
 103                 break
 104             if ((_iph > 10) and (abs(_iph - _h) < 2)):
 105                 # print "within 2"
 106                 break
 107             if ((_iph > 100) and (abs(_iph - _h) < 10)):
 108                 # print "within 10"
 109                 break
 110             if ((_iph > 1000) and (abs(_iph - _h) < 40)):
 111                 # print "within 40"
 112                 break
 113             if _i > 25:
 114                 # print "25 iterations"
 115                 break
 116             #
 117             # bah, another iteration
 118             #
 119             _d = abs(_h - _iph)
 120             if  _d < _diff:
 121                 _diff = _d
 122                 _ofs = _fs
 123                 _fs = (_fs * _ph)/float(_h)
 124             else:
 125                 # split the difference in the changed font size
 126                 # and try again, but do not reset the old font
 127                 # size
 128                 _fs = _ofs + ((_fs - _ofs)/2.0)
 129             # print "adjusted font size: %g" % (_fs)
 130             _i = _i + 1
 131     #
 132     # with the layout sized "correctly", calculate the TextBlock width
 133     #
 134     _w, _h = _layout.get_size()
 135     _tw = (_w * _th)/float(_h)
 136     # print "TextBlock width: %g" % _tw
 137     tblock.setBounds(_tw, _th)
 138     tblock.setFontScale(_fs)
 139     _layout = None
 140
 141 def _make_pango_layout(gtkimage, text, family, style, weight, size):
 142     _layout = gtkimage.getDA().create_pango_layout(text)
 143     _fd = pango.FontDescription()
 144     _fd.set_family(family)
 145     if style == TextStyle.FONT_NORMAL:
 146         _style = pango.STYLE_NORMAL
 147     elif style == TextStyle.FONT_OBLIQUE:
 148         _style = pango.STYLE_OBLIQUE
 149     elif style == TextStyle.FONT_ITALIC:
 150         _style = pango.STYLE_ITALIC
 151     else:
 152         raise ValueError, "Unexpected font style: %d" % style
 153     _fd.set_style(_style)
 154     if weight == TextStyle.WEIGHT_NORMAL:
 155         _weight = pango.WEIGHT_NORMAL
 156     elif weight == TextStyle.WEIGHT_LIGHT:
 157         _weight = pango.WEIGHT_LIGHT
 158     elif weight == TextStyle.WEIGHT_BOLD:
 159         _weight = pango.WEIGHT_BOLD
 160     elif weight == TextStyle.WEIGHT_HEAVY:
 161         _weight = pango.WEIGHT_HEAVY
 162     else:
 163         raise ValueError, "Unexpected font weight: %d" % weight
 164     _fd.set_weight(_weight)
 165     _sz = int(pango.SCALE * (size/gtkimage.getUnitsPerPixel()))
 166     if _sz < pango.SCALE:
 167         _sz = pango.SCALE
 168     _fd.set_size(_sz)
 169     _layout.set_font_description(_fd)
 170     return _layout
 171
 172 def text_button_press(gtkimage, widget, event, tool):
 173     _tol = gtkimage.getTolerance()
 174     _image = gtkimage.getImage()
 175     _x, _y = _image.getCurrentPoint()
 176     _pt, _flag = _image.findPoint(_x, _y, _tol)
 177     if _pt is not None:
 178         _x, _y = _pt.getCoords()
 179     tool.getTextBlock().setLocation(_x, _y)
 180     _image.startAction()
 181     try:
 182         tool.create(_image)
 183     finally:
 184         _image.endAction()
 185     # tool.clearCurrentPoint()
 186     return True
 187
 188 def text_motion_notify(gtkimage, widget, event, tool):
 189     _tblock = tool.getTextBlock()
 190     _tw, _th = tool.getPixelSize()
 191     _gc = gtkimage.getGC()
 192     _x = int(event.x)
 193     _y = int(event.y)
 194     _align = _tblock.getAlignment()
 195     if _align == TextStyle.ALIGN_LEFT:
 196         _xoff = 0
 197     elif _align == TextStyle.ALIGN_CENTER:
 198         _xoff = _tw//2
 199     elif _align == TextStyle.ALIGN_RIGHT:
 200         _xoff = _tw
 201     else:
 202         raise ValueError, "Unexpected alignment value: %d" % _align
 203     _cp = tool.getCurrentPoint()
 204     if _cp is not None:
 205         _xc, _yc = _cp
 206         _xc = _xc - _xoff
 207         widget.window.draw_rectangle(_gc, False, _xc, _yc, _tw, _th)
 208     tool.setCurrentPoint(_x, _y)
 209     _x = _x - _xoff
 210     widget.window.draw_rectangle(_gc, False, _x, _y, _tw, _th)
 211     return True
 212
 213 def text_add_init(gtkimage, tool=None):
 214     _image = gtkimage.getImage()
 215     _x, _y = _image.getCurrentPoint()
 216     _tool = _image.getTool()
 217     _text = _tool.getText()
 218     _ts = _image.getOption('TEXT_STYLE')
 219     _tb = TextBlock(_x, _y, _text, _ts)
 220     _f = _image.getOption('FONT_FAMILY')
 221     if _f != _ts.getFamily():
 222         _tb.setFamily(_f)
 223     _s = _image.getOption('FONT_STYLE')
 224     if _s != _ts.getStyle():
 225         _tb.setStyle(_s)
 226     _w = _image.getOption('FONT_WEIGHT')
 227     if _w != _ts.getWeight():
 228         _tb.setWeight(_w)
 229     _c = _image.getOption('FONT_COLOR')
 230     if _c != _ts.getColor():
 231         _tb.setColor(_c)
 232     _sz = _image.getOption('TEXT_SIZE')
 233     if abs(_sz - _ts.getSize()) > 1e-10:
 234         _tb.setSize(_sz)
 235     _a = _image.getOption('TEXT_ANGLE')
 236     if abs(_a - _ts.getAngle()) > 1e-10:
 237         _tb.setAngle(_a)
 238     _al = _image.getOption('TEXT_ALIGNMENT')
 239     if _al != _ts.getAlignment():
 240         _tb.setAlignment(_al)
 241     _tool.setTextBlock(_tb)
 242     _layout = _make_pango_layout(gtkimage, _text, _f, _s, _w, _sz)
 243     _tool.setLayout(_layout)
 244     _lw, _lh = _layout.get_pixel_size()
 245     _tool.setPixelSize(_lw, _lh)
 246     _upp = gtkimage.getUnitsPerPixel()
 247     #
 248     # the width and height calculations can be somewhat inaccurate
 249     # as the unitsPerPixel value gets large
 250     #
 251     _w = _lw * _upp
 252     _h = _lh * _upp
 253     _tool.setBounds(_w, _h)
 254     _tool.setHandler("motion_notify", text_motion_notify)
 255     _tool.setHandler("button_press", text_button_press)
 256     gtkimage.setPrompt(_('Click where to place the text'))
 257     _gc = gtkimage.getGC()
 258     _gc.set_line_attributes(1, gtk.gdk.LINE_SOLID,
 259                             gtk.gdk.CAP_BUTT, gtk.gdk.JOIN_MITER)
 260     _gc.set_function(gtk.gdk.INVERT)
 261
 262 def text_add_dialog(gtkimage):
 263     _window = gtkimage.getWindow()
 264     _dialog = gtk.Dialog(_('Enter text'), _window,
 265                          gtk.DIALOG_MODAL | gtk.DIALOG_DESTROY_WITH_PARENT,
 266                          (gtk.STOCK_OK, gtk.RESPONSE_OK,
 267                           gtk.STOCK_CANCEL, gtk.RESPONSE_CANCEL))
 268     _tb = gtk.TextBuffer()
 269     _tv = gtk.TextView(_tb)
 270     _sw = gtk.ScrolledWindow()
 271     _sw.set_size_request(400, 300)
 272     _sw.add_with_viewport(_tv)
 273     _dialog.vbox.pack_start(_sw, False, False, 0)
 274     _dialog.show_all()
 275     _text = None
 276     _response = _dialog.run()
 277     if _response == gtk.RESPONSE_OK:
 278         _start_iter, _end_iter = _tb.get_bounds()
 279         _text = _tb.get_text(_start_iter, _end_iter)
 280     _dialog.destroy()
 281     return _text
 282