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Text File | 1996-05-19 | 14.7 KB | 470 lines | [TEXT/Pyth] |
- # Text formatting abstractions
- # Note -- this module is obsolete, it's too slow anyway
-
-
- import string
- import Para
-
-
- # A formatter back-end object has one method that is called by the formatter:
- # addpara(p), where p is a paragraph object. For example:
-
-
- # Formatter back-end to do nothing at all with the paragraphs
- class NullBackEnd:
- #
- def __init__(self):
- pass
- #
- def addpara(self, p):
- pass
- #
- def bgn_anchor(self, id):
- pass
- #
- def end_anchor(self, id):
- pass
-
-
- # Formatter back-end to collect the paragraphs in a list
- class SavingBackEnd(NullBackEnd):
- #
- def __init__(self):
- self.paralist = []
- #
- def addpara(self, p):
- self.paralist.append(p)
- #
- def hitcheck(self, h, v):
- hits = []
- for p in self.paralist:
- if p.top <= v <= p.bottom:
- for id in p.hitcheck(h, v):
- if id not in hits:
- hits.append(id)
- return hits
- #
- def extract(self):
- text = ''
- for p in self.paralist:
- text = text + (p.extract())
- return text
- #
- def extractpart(self, long1, long2):
- if long1 > long2: long1, long2 = long2, long1
- para1, pos1 = long1
- para2, pos2 = long2
- text = ''
- while para1 < para2:
- ptext = self.paralist[para1].extract()
- text = text + ptext[pos1:]
- pos1 = 0
- para1 = para1 + 1
- ptext = self.paralist[para2].extract()
- return text + ptext[pos1:pos2]
- #
- def whereis(self, d, h, v):
- total = 0
- for i in range(len(self.paralist)):
- p = self.paralist[i]
- result = p.whereis(d, h, v)
- if result <> None:
- return i, result
- return None
- #
- def roundtowords(self, long1, long2):
- i, offset = long1
- text = self.paralist[i].extract()
- while offset > 0 and text[offset-1] <> ' ': offset = offset-1
- long1 = i, offset
- #
- i, offset = long2
- text = self.paralist[i].extract()
- n = len(text)
- while offset < n-1 and text[offset] <> ' ': offset = offset+1
- long2 = i, offset
- #
- return long1, long2
- #
- def roundtoparagraphs(self, long1, long2):
- long1 = long1[0], 0
- long2 = long2[0], len(self.paralist[long2[0]].extract())
- return long1, long2
-
-
- # Formatter back-end to send the text directly to the drawing object
- class WritingBackEnd(NullBackEnd):
- #
- def __init__(self, d, width):
- self.d = d
- self.width = width
- self.lineno = 0
- #
- def addpara(self, p):
- self.lineno = p.render(self.d, 0, self.lineno, self.width)
-
-
- # A formatter receives a stream of formatting instructions and assembles
- # these into a stream of paragraphs on to a back-end. The assembly is
- # parametrized by a text measurement object, which must match the output
- # operations of the back-end. The back-end is responsible for splitting
- # paragraphs up in lines of a given maximum width. (This is done because
- # in a windowing environment, when the window size changes, there is no
- # need to redo the assembly into paragraphs, but the splitting into lines
- # must be done taking the new window size into account.)
-
-
- # Formatter base class. Initialize it with a text measurement object,
- # which is used for text measurements, and a back-end object,
- # which receives the completed paragraphs. The formatting methods are:
- # setfont(font)
- # setleftindent(nspaces)
- # setjust(type) where type is 'l', 'c', 'r', or 'lr'
- # flush()
- # vspace(nlines)
- # needvspace(nlines)
- # addword(word, nspaces)
- class BaseFormatter:
- #
- def __init__(self, d, b):
- # Drawing object used for text measurements
- self.d = d
- #
- # BackEnd object receiving completed paragraphs
- self.b = b
- #
- # Parameters of the formatting model
- self.leftindent = 0
- self.just = 'l'
- self.font = None
- self.blanklines = 0
- #
- # Parameters derived from the current font
- self.space = d.textwidth(' ')
- self.line = d.lineheight()
- self.ascent = d.baseline()
- self.descent = self.line - self.ascent
- #
- # Parameter derived from the default font
- self.n_space = self.space
- #
- # Current paragraph being built
- self.para = None
- self.nospace = 1
- #
- # Font to set on the next word
- self.nextfont = None
- #
- def newpara(self):
- return Para.Para()
- #
- def setfont(self, font):
- if font == None: return
- self.font = self.nextfont = font
- d = self.d
- d.setfont(font)
- self.space = d.textwidth(' ')
- self.line = d.lineheight()
- self.ascent = d.baseline()
- self.descent = self.line - self.ascent
- #
- def setleftindent(self, nspaces):
- self.leftindent = int(self.n_space * nspaces)
- if self.para:
- hang = self.leftindent - self.para.indent_left
- if hang > 0 and self.para.getlength() <= hang:
- self.para.makehangingtag(hang)
- self.nospace = 1
- else:
- self.flush()
- #
- def setrightindent(self, nspaces):
- self.rightindent = int(self.n_space * nspaces)
- if self.para:
- self.para.indent_right = self.rightindent
- self.flush()
- #
- def setjust(self, just):
- self.just = just
- if self.para:
- self.para.just = self.just
- #
- def flush(self):
- if self.para:
- self.b.addpara(self.para)
- self.para = None
- if self.font <> None:
- self.d.setfont(self.font)
- self.nospace = 1
- #
- def vspace(self, nlines):
- self.flush()
- if nlines > 0:
- self.para = self.newpara()
- tuple = None, '', 0, 0, 0, int(nlines*self.line), 0
- self.para.words.append(tuple)
- self.flush()
- self.blanklines = self.blanklines + nlines
- #
- def needvspace(self, nlines):
- self.flush() # Just to be sure
- if nlines > self.blanklines:
- self.vspace(nlines - self.blanklines)
- #
- def addword(self, text, space):
- if self.nospace and not text:
- return
- self.nospace = 0
- self.blanklines = 0
- if not self.para:
- self.para = self.newpara()
- self.para.indent_left = self.leftindent
- self.para.just = self.just
- self.nextfont = self.font
- space = int(space * self.space)
- self.para.words.append(self.nextfont, text, \
- self.d.textwidth(text), space, space, \
- self.ascent, self.descent)
- self.nextfont = None
- #
- def bgn_anchor(self, id):
- if not self.para:
- self.nospace = 0
- self.addword('', 0)
- self.para.bgn_anchor(id)
- #
- def end_anchor(self, id):
- if not self.para:
- self.nospace = 0
- self.addword('', 0)
- self.para.end_anchor(id)
-
-
- # Measuring object for measuring text as viewed on a tty
- class NullMeasurer:
- #
- def __init__(self):
- pass
- #
- def setfont(self, font):
-