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+# Text formatting abstractions
+
+
+# Oft-used type object
+Int = type(0)
+
+
+# Represent a paragraph. This is a list of words with associated
+# font and size information, plus indents and justification for the
+# entire paragraph.
+# Once the words have been added to a paragraph, it can be laid out
+# for different line widths. Once laid out, it can be rendered at
+# different screen locations. Once rendered, it can be queried
+# for mouse hits, and parts of the text can be highlighted
+class Para:
+ #
+ def __init__(self):
+ self.words = [] # The words
+ self.just = 'l' # Justification: 'l', 'r', 'lr' or 'c'
+ self.indent_left = self.indent_right = self.indent_hang = 0
+ # Final lay-out parameters, may change
+ self.left = self.top = self.right = self.bottom = \
+ self.width = self.height = self.lines = None
+ #
+ # Add a word, computing size information for it.
+ # Words may also be added manually by appending to self.words
+ # Each word should be a 7-tuple:
+ # (font, text, width, space, stretch, ascent, descent)
+ def addword(self, d, font, text, space, stretch):
+ if font <> None:
+ d.setfont(font)
+ width = d.textwidth(text)
+ ascent = d.baseline()
+ descent = d.lineheight() - ascent
+ spw = d.textwidth(' ')
+ space = space * spw
+ stretch = stretch * spw
+ tuple = (font, text, width, space, stretch, ascent, descent)
+ self.words.append(tuple)
+ #
+ # Hooks to begin and end anchors -- insert numbers in the word list!
+ def bgn_anchor(self, id):
+ self.words.append(id)
+ #
+ def end_anchor(self, id):
+ self.words.append(0)
+ #
+ # Return the total length (width) of the text added so far, in pixels
+ def getlength(self):
+ total = 0
+ for word in self.words:
+ if type(word) <> Int:
+ total = total + word[2] + word[3]
+ return total
+ #
+ # Tab to a given position (relative to the current left indent):
+ # remove all stretch, add fixed space up to the new indent.
+ # If the current position is already beying the tab stop,
+ # don't add any new space (but still remove the stretch)
+ def tabto(self, tab):
+ total = 0
+ as, de = 1, 0
+ for i in range(len(self.words)):
+ word = self.words[i]
+ if type(word) == Int: continue
+ fo, te, wi, sp, st, as, de = word
+ self.words[i] = fo, te, wi, sp, 0, as, de
+ total = total + wi + sp
+ if total < tab:
+ self.words.append(None, '', 0, tab-total, 0, as, de)
+ #
+ # Make a hanging tag: tab to hang, increment indent_left by hang,
+ # and reset indent_hang to -hang
+ def makehangingtag(self, hang):
+ self.tabto(hang)
+ self.indent_left = self.indent_left + hang
+ self.indent_hang = -hang
+ #
+ # Decide where the line breaks will be given some screen width
+ def layout(self, linewidth):
+ self.width = linewidth
+ height = 0
+ self.lines = lines = []
+ avail1 = self.width - self.indent_left - self.indent_right
+ avail = avail1 - self.indent_hang
+ words = self.words
+ i = 0
+ n = len(words)
+ lastfont = None
+ while i < n:
+ firstfont = lastfont
+ charcount = 0
+ width = 0
+ stretch = 0
+ ascent = 0
+ descent = 0
+ lsp = 0
+ j = i
+ while i < n:
+ word = words[i]
+ if type(word) == Int:
+ if word > 0 and width >= avail:
+ break
+ i = i+1
+ continue
+ fo, te, wi, sp, st, as, de = word
+ if width + wi > avail and width > 0 and wi > 0:
+ break
+ if fo <> None:
+ lastfont = fo
+ if width == 0:
+ firstfont = fo
+ charcount = charcount + len(te) + (sp > 0)
+ width = width + wi + sp
+ lsp = sp
+ stretch = stretch + st
+ lst = st
+ ascent = max(ascent, as)
+ descent = max(descent, de)
+ i = i+1
+ while i > j and type(words[i-1]) == Int and \
+ words[i-1] > 0: i = i-1
+ width = width - lsp
+ if i < n:
+ stretch = stretch - lst
+ else:
+ stretch = 0
+ tuple = i-j, firstfont, charcount, width, stretch, \
+ ascent, descent
+ lines.append(tuple)
+ height = height + ascent + descent
+ avail = avail1
+ self.height = height
+ #
+ # Call a function for all words in a line
+ def visit(self, wordfunc, anchorfunc):
+ avail1 = self.width - self.indent_left - self.indent_right
+ avail = avail1 - self.indent_hang
+ v = self.top
+ i = 0
+ for tuple in self.lines:
+ wordcount, firstfont, charcount, width, stretch, \
+ ascent, descent = tuple
+ h = self.left + self.indent_left
+ if i == 0: h = h + self.indent_hang
+ extra = 0
+ if self.just == 'r': h = h + avail - width
+ elif self.just == 'c': h = h + (avail - width) / 2
+ elif self.just == 'lr' and stretch > 0:
+ extra = avail - width
+ v2 = v + ascent + descent
+ for j in range(i, i+wordcount):
+ word = self.words[j]
+ if type(word) == Int:
+ ok = anchorfunc(self, tuple, word, \
+ h, v)
+ if ok <> None: return ok
+ continue
+ fo, te, wi, sp, st, as, de = word
+ if extra > 0 and stretch > 0:
+ ex = extra * st / stretch
+ extra = extra - ex
+ stretch = stretch - st
+ else:
+ ex = 0
+ h2 = h + wi + sp + ex
+ ok = wordfunc(self, tuple, word, h, v, \
+ h2, v2, (j==i), (j==i+wordcount-1))
+ if ok <> None: return ok
+ h = h2
+ v = v2
+ i = i + wordcount
+ avail = avail1
+ #
+ # Render a paragraph in "drawing object" d, using the rectangle
+ # given by (left, top, right) with an unspecified bottom.
+ # Return the computed bottom of the text.
+ def render(self, d, left, top, right):
+ if self.width <> right-left:
+ self.layout(right-left)
+ self.left = left
+ self.top = top
+ self.right = right
+ self.bottom = self.top + self.height
+ self.anchorid = 0
+ try:
+ self.d = d
+ self.visit(self.__class__._renderword, \
+ self.__class__._renderanchor)
+ finally:
+ self.d = None
+ return self.bottom
+ #
+ def _renderword(self, tuple, word, h, v, h2, v2, isfirst, islast):
+ if word[0] <> None: self.d.setfont(word[0])
+ baseline = v + tuple[5]
+ self.d.text((h, baseline - word[5]), word[1])
+ if self.anchorid > 0:
+ self.d.line((h, baseline+2), (h2, baseline+2))
+ #
+ def _renderanchor(self, tuple, word, h, v):
+ self.anchorid = word
+ #
+ # Return which anchor(s) was hit by the mouse
+ def hitcheck(self, mouseh, mousev):
+ self.mouseh = mouseh
+ self.mousev = mousev
+ self.anchorid = 0
+ self.hits = []
+ self.visit(self.__class__._hitcheckword, \
+ self.__class__._hitcheckanchor)
+ return self.hits
+ #
+ def _hitcheckword(self, tuple, word, h, v, h2, v2, isfirst, islast):
+ if self.anchorid > 0 and h <= self.mouseh <= h2 and \
+ v <= self.mousev <= v2:
+ self.hits.append(self.anchorid)
+ #
+ def _hitcheckanchor(self, tuple, word, h, v):
+ self.anchorid = word
+ #
+ # Return whether the given anchor id is present
+ def hasanchor(self, id):
+ return id in self.words or -id in self.words
+ #
+ # Extract the raw text from the word list, substituting one space
+ # for non-empty inter-word space, and terminating with '\n'
+ def extract(self):
+ text = ''
+ for w in self.words:
+ if type(w) <> Int:
+ word = w[1]
+ if w[3]: word = word + ' '
+ text = text + word
+ return text + '\n'
+ #
+ # Return which character position was hit by the mouse, as
+ # an offset in the entire text as returned by extract().
+ # Return None if the mouse was not in this paragraph
+ def whereis(self, d, mouseh, mousev):
+ if mousev < self.top or mousev > self.bottom:
+ return None
+ self.mouseh = mouseh
+ self.mousev = mousev
+ self.lastfont = None
+ self.charcount = 0
+ try:
+ self.d = d
+ return self.visit(self.__class__._whereisword, \
+ self.__class__._whereisanchor)
+ finally:
+ self.d = None
+ #
+ def _whereisword(self, tuple, word, h1, v1, h2, v2, isfirst, islast):
+ fo, te, wi, sp, st, as, de = word
+ if fo <> None: self.lastfont = fo
+ h = h1
+ if isfirst: h1 = 0
+ if islast: h2 = 999999
+ if not (v1 <= self.mousev <= v2 and h1 <= self.mouseh <= h2):
+ self.charcount = self.charcount + len(te) + (sp > 0)
+ return
+ if self.lastfont <> None:
+ self.d.setfont(self.lastfont)
+ cc = 0
+ for c in te:
+ cw = self.d.textwidth(c)
+ if self.mouseh <= h + cw/2:
+ return self.charcount + cc
+ cc = cc+1
+ h = h+cw
+ self.charcount = self.charcount + cc
+ if self.mouseh <= (h+h2) / 2:
+ return self.charcount
+ else:
+ return self.charcount + 1
+ #
+ def _whereisanchor(self, tuple, word, h, v):
+ pass
+ #
+ # Return screen position corresponding to position in paragraph.
+ # Return tuple (h, vtop, vbaseline, vbottom).
+ # This is more or less the inverse of whereis()
+ def screenpos(self, d, pos):
+ if pos < 0:
+ ascent, descent = self.lines[0][5:7]
+ return self.left, self.top, self.top + ascent, \
+ self.top + ascent + descent
+ self.pos = pos
+ self.lastfont = None
+ try:
+ self.d = d
+ ok = self.visit(self.__class__._screenposword, \
+ self.__class__._screenposanchor)
+ finally:
+ self.d = None
+ if ok == None:
+ ascent, descent = self.lines[-1][5:7]
+ ok = self.right, self.bottom - ascent - descent, \
+ self.bottom - descent, self.bottom
+ return ok
+ #
+ def _screenposword(self, tuple, word, h1, v1, h2, v2, isfirst, islast):
+ fo, te, wi, sp, st, as, de = word
+ if fo <> None: self.lastfont = fo
+ cc = len(te) + (sp > 0)
+ if self.pos > cc:
+ self.pos = self.pos - cc
+ return
+ if self.pos < cc:
+ self.d.setfont(self.lastfont)
+ h = h1 + self.d.textwidth(te[:self.pos])
+ else:
+ h = h2
+ ascent, descent = tuple[5:7]
+ return h, v1, v1+ascent, v2
+ #
+ def _screenposanchor(self, tuple, word, h, v):
+ pass
+ #
+ # Invert the stretch of text between pos1 and pos2.
+ # If pos1 is None, the beginning is implied;
+ # if pos2 is None, the end is implied.
+ # Undoes its own effect when called again with the same arguments
+ def invert(self, d, pos1, pos2):
+ if pos1 == None:
+ pos1 = self.left, self.top, self.top, self.top
+ else:
+ pos1 = self.screenpos(d, pos1)
+ if pos2 == None:
+ pos2 = self.right, self.bottom,self.bottom,self.bottom
+ else:
+ pos2 = self.screenpos(d, pos2)
+ h1, top1, baseline1, bottom1 = pos1
+ h2, top2, baseline2, bottom2 = pos2
+ if bottom1 <= top2:
+ d.invert((h1, top1), (self.right, bottom1))
+ h1 = self.left
+ if bottom1 < top2:
+ d.invert((h1, bottom1), (self.right, top2))
+ top1, bottom1 = top2, bottom2
+ d.invert((h1, top1), (h2, bottom2))
+
+
+# Test class Para
+# XXX This was last used on the Mac, hence the weird fonts...
+def test():
+ import stdwin
+ from stdwinevents import *
+ words = 'The', 'quick', 'brown', 'fox', 'jumps', 'over', \
+ 'the', 'lazy', 'dog.'
+ paralist = []
+ for just in 'l', 'r', 'lr', 'c':
+ p = Para()
+ p.just = just
+ p.addword(stdwin, ('New York', 'p', 12), words[0], 1, 1)
+ for word in words[1:-1]:
+ p.addword(stdwin, None, word, 1, 1)
+ p.addword(stdwin, None, words[-1], 2, 4)
+ p.addword(stdwin, ('New York', 'b', 18), 'Bye!', 0, 0)
+ p.addword(stdwin, ('New York', 'p', 10), 'Bye!', 0, 0)
+ paralist.append(p)
+ window = stdwin.open('Para.test()')
+ start = stop = selpara = None
+ while 1:
+ etype, win, detail = stdwin.getevent()
+ if etype == WE_CLOSE:
+ break
+ if etype == WE_SIZE:
+ window.change((0, 0), (1000, 1000))
+ if etype == WE_DRAW:
+ width, height = window.getwinsize()
+ d = None
+ try:
+ d = window.begindrawing()
+ d.cliprect(detail)
+ d.erase(detail)
+ v = 0
+ for p in paralist:
+ v = p.render(d, 0, v, width)
+ if p == selpara and \
+ start <> None and stop <> None:
+ p.invert(d, start, stop)
+ finally:
+ if d: d.close()
+ if etype == WE_MOUSE_DOWN:
+ if selpara and start <> None and stop <> None:
+ d = window.begindrawing()
+ selpara.invert(d, start, stop)
+ d.close()
+ start = stop = selpara = None
+ mouseh, mousev = detail[0]
+ for p in paralist:
+ start = p.whereis(stdwin, mouseh, mousev)
+ if start <> None:
+ selpara = p
+ break
+ if etype == WE_MOUSE_UP and start <> None and selpara:
+ mouseh, mousev = detail[0]
+ stop = selpara.whereis(stdwin, mouseh, mousev)
+ if stop == None: start = selpara = None
+ else:
+ if start > stop:
+ start, stop = stop, start
+ d = window.begindrawing()
+ selpara.invert(d, start, stop)
+ d.close()
+ window.close()