# Text formatting abstractions
# Note -- this module is obsolete, it's too slow anyway
# 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 is not 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) is not 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 at 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) is 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) is 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 is not 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]) is 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) is Int:
ok = anchorfunc(self, tuple, word, \
h, v)
if ok is not 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 is not 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] is not 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) is not 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 is not 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 is not 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 is 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 is not 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 is None:
pos1 = self.left, self.top, self.top, self.top
else:
pos1 = self.screenpos(d, pos1)
if pos2 is 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))
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