svgfig.Path Class Reference

Public Member Functions
def	__init__ (self, d=[], attr)
def	__repr__ (self)
def	parse (self, pathdata)
def	parse_boolean (self, index, pathdata)
def	parse_command (self, index, pathdata)
def	parse_number (self, index, pathdata)
def	parse_whitespace (self, index, pathdata)
def	SVG (self, trans=None)

Public Attributes
	attr
	d

Static Public Attributes
dictionary	defaults = {}

Detailed Description

Path represents an SVG path, an arbitrary set of curves and
straight segments. Unlike SVG("path", d="..."), Path stores
coordinates as a list of numbers, rather than a string, so that it is
transformable in a Fig.

Path(d, attribute=value)

d                       required        path data
attribute=value pairs   keyword list    SVG attributes

See http://www.w3.org/TR/SVG/paths.html for specification of paths
from text.

Internally, Path data is a list of tuples with these definitions:

    * ("Z/z",): close the current path
    * ("H/h", x) or ("V/v", y): a horizontal or vertical line
      segment to x or y
    * ("M/m/L/l/T/t", x, y, global): moveto, lineto, or smooth
      quadratic curveto point (x, y). If global=True, (x, y) should
      not be transformed.
    * ("S/sQ/q", cx, cy, cglobal, x, y, global): polybezier or
      smooth quadratic curveto point (x, y) using (cx, cy) as a
      control point. If cglobal or global=True, (cx, cy) or (x, y)
      should not be transformed.
    * ("C/c", c1x, c1y, c1global, c2x, c2y, c2global, x, y, global):
      cubic curveto point (x, y) using (c1x, c1y) and (c2x, c2y) as
      control points. If c1global, c2global, or global=True, (c1x, c1y),
      (c2x, c2y), or (x, y) should not be transformed.
    * ("A/a", rx, ry, rglobal, x-axis-rotation, angle, large-arc-flag,
      sweep-flag, x, y, global): arcto point (x, y) using the
      aforementioned parameters.
    * (",/.", rx, ry, rglobal, angle, x, y, global): an ellipse at
      point (x, y) with radii (rx, ry). If angle is 0, the whole
      ellipse is drawn; otherwise, a partial ellipse is drawn.

Definition at line 1021 of file svgfig.py.

Constructor & Destructor Documentation

def svgfig.Path.__init__	(		self,
			d = [],
			attr
	)

Definition at line 1063 of file svgfig.py.

  def __init__(self, d=[], **attr):
    if isinstance(d, str): self.d = self.parse(d)
    else: self.d = list(d)

    self.attr = dict(self.defaults)
    self.attr.update(attr)

Member Function Documentation

def svgfig.Path.__repr__

(

self

)

Definition at line 1060 of file svgfig.py.

References svgfig.SVG.attr, svgfig.Path.attr, svgfig.Fig.d, svgfig.Plot.d, svgfig.Frame.d, and svgfig.Path.d.

Referenced by data_sources.json_file.__str__().

  def __repr__(self):
    return "<Path (%d nodes) %s>" % (len(self.d), self.attr)

def svgfig.Path.parse	(		self,
			pathdata
	)

Parses text-commands, converting them into a list of tuples.
Called by the constructor.

Definition at line 1118 of file svgfig.py.

References svgfig.Path.parse_boolean(), svgfig.Path.parse_command(), svgfig.Path.parse_number(), and svgfig.Path.parse_whitespace().

  def parse(self, pathdata):
    """Parses text-commands, converting them into a list of tuples.
    Called by the constructor."""
    output = []
    index = 0
    while True:
      command, index, pathdata = self.parse_command(index, pathdata)
      index, pathdata = self.parse_whitespace(index, pathdata)

      if command == None and index == len(pathdata): break  # this is the normal way out of the loop
      if command in ("Z", "z"):
        output.append((command,))

      ######################
      elif command in ("H", "h", "V", "v"):
        errstring = "Path command \"%s\" requires a number at index %d" % (command, index)
        num1, index, pathdata = self.parse_number(index, pathdata)
        if num1 == None: raise ValueError(errstring)

        while num1 != None:
          output.append((command, num1))
          num1, index, pathdata = self.parse_number(index, pathdata)

      ######################
      elif command in ("M", "m", "L", "l", "T", "t"):
        errstring = "Path command \"%s\" requires an x,y pair at index %d" % (command, index)
        num1, index, pathdata = self.parse_number(index, pathdata)
        num2, index, pathdata = self.parse_number(index, pathdata)

        if num1 == None: raise ValueError(errstring)

        while num1 != None:
          if num2 == None: raise ValueError(errstring)
          output.append((command, num1, num2, False))

          num1, index, pathdata = self.parse_number(index, pathdata)
          num2, index, pathdata = self.parse_number(index, pathdata)

      ######################
      elif command in ("S", "s", "Q", "q"):
        errstring = "Path command \"%s\" requires a cx,cy,x,y quadruplet at index %d" % (command, index)
        num1, index, pathdata = self.parse_number(index, pathdata)
        num2, index, pathdata = self.parse_number(index, pathdata)
        num3, index, pathdata = self.parse_number(index, pathdata)
        num4, index, pathdata = self.parse_number(index, pathdata)

        if num1 == None: raise ValueError(errstring)

        while num1 != None:
          if num2 == None or num3 == None or num4 == None: raise ValueError(errstring)
          output.append((command, num1, num2, False, num3, num4, False))

          num1, index, pathdata = self.parse_number(index, pathdata)
          num2, index, pathdata = self.parse_number(index, pathdata)
          num3, index, pathdata = self.parse_number(index, pathdata)
          num4, index, pathdata = self.parse_number(index, pathdata)
          
      ######################
      elif command in ("C", "c"):
        errstring = "Path command \"%s\" requires a c1x,c1y,c2x,c2y,x,y sextuplet at index %d" % (command, index)
        num1, index, pathdata = self.parse_number(index, pathdata)
        num2, index, pathdata = self.parse_number(index, pathdata)
        num3, index, pathdata = self.parse_number(index, pathdata)
        num4, index, pathdata = self.parse_number(index, pathdata)
        num5, index, pathdata = self.parse_number(index, pathdata)
        num6, index, pathdata = self.parse_number(index, pathdata)
        
        if num1 == None: raise ValueError(errstring)

        while num1 != None:
          if num2 == None or num3 == None or num4 == None or num5 == None or num6 == None: raise ValueError(errstring)

          output.append((command, num1, num2, False, num3, num4, False, num5, num6, False))

          num1, index, pathdata = self.parse_number(index, pathdata)
          num2, index, pathdata = self.parse_number(index, pathdata)
          num3, index, pathdata = self.parse_number(index, pathdata)
          num4, index, pathdata = self.parse_number(index, pathdata)
          num5, index, pathdata = self.parse_number(index, pathdata)
          num6, index, pathdata = self.parse_number(index, pathdata)

      ######################
      elif command in ("A", "a"):
        errstring = "Path command \"%s\" requires a rx,ry,angle,large-arc-flag,sweep-flag,x,y septuplet at index %d" % (command, index)
        num1, index, pathdata = self.parse_number(index, pathdata)
        num2, index, pathdata = self.parse_number(index, pathdata)
        num3, index, pathdata = self.parse_number(index, pathdata)
        num4, index, pathdata = self.parse_boolean(index, pathdata)
        num5, index, pathdata = self.parse_boolean(index, pathdata)
        num6, index, pathdata = self.parse_number(index, pathdata)
        num7, index, pathdata = self.parse_number(index, pathdata)

        if num1 == None: raise ValueError(errstring)

        while num1 != None:
          if num2 == None or num3 == None or num4 == None or num5 == None or num6 == None or num7 == None: raise ValueError(errstring)

          output.append((command, num1, num2, False, num3, num4, num5, num6, num7, False))

          num1, index, pathdata = self.parse_number(index, pathdata)
          num2, index, pathdata = self.parse_number(index, pathdata)
          num3, index, pathdata = self.parse_number(index, pathdata)
          num4, index, pathdata = self.parse_boolean(index, pathdata)
          num5, index, pathdata = self.parse_boolean(index, pathdata)
          num6, index, pathdata = self.parse_number(index, pathdata)
          num7, index, pathdata = self.parse_number(index, pathdata)

    return output

def svgfig.Path.parse_boolean	(		self,
			index,
			pathdata
	)

Part of Path's text-command parsing algorithm; used internally.

Definition at line 1105 of file svgfig.py.

References createfilelist.int, and svgfig.Path.parse_whitespace().

Referenced by svgfig.Path.parse().

  def parse_boolean(self, index, pathdata):
    """Part of Path's text-command parsing algorithm; used internally."""
    index, pathdata = self.parse_whitespace(index, pathdata)

    if index >= len(pathdata): return None, index, pathdata
    first_digit = pathdata[index]

    if first_digit in ("0", "1"):
      index += 1
      return int(first_digit), index, pathdata
    else:
      return None, index, pathdata

def svgfig.Path.parse_command	(		self,
			index,
			pathdata
	)

Part of Path's text-command parsing algorithm; used internally.

Definition at line 1075 of file svgfig.py.

References svgfig.Path.parse_whitespace().

Referenced by svgfig.Path.parse().

  def parse_command(self, index, pathdata):
    """Part of Path's text-command parsing algorithm; used internally."""
    index, pathdata = self.parse_whitespace(index, pathdata)

    if index >= len(pathdata): return None, index, pathdata
    command = pathdata[index]
    if "A" <= command <= "Z" or "a" <= command <= "z":
      index += 1
      return command, index, pathdata
    else: 
      return None, index, pathdata

def svgfig.Path.parse_number	(		self,
			index,
			pathdata
	)

Part of Path's text-command parsing algorithm; used internally.

Definition at line 1087 of file svgfig.py.

References objects.autophobj.float, and svgfig.Path.parse_whitespace().

Referenced by svgfig.Path.parse().

  def parse_number(self, index, pathdata):
    """Part of Path's text-command parsing algorithm; used internally."""
    index, pathdata = self.parse_whitespace(index, pathdata)

    if index >= len(pathdata): return None, index, pathdata
    first_digit = pathdata[index]

    if "0" <= first_digit <= "9" or first_digit in ("-", "+", "."):
      start = index
      while index < len(pathdata) and ("0" <= pathdata[index] <= "9" or pathdata[index] in ("-", "+", ".", "e", "E")):
        index += 1
      end = index

      index = end
      return float(pathdata[start:end]), index, pathdata
    else: 
      return None, index, pathdata

def svgfig.Path.parse_whitespace	(		self,
			index,
			pathdata
	)

Part of Path's text-command parsing algorithm; used internally.

Definition at line 1070 of file svgfig.py.

Referenced by svgfig.Path.parse(), svgfig.Path.parse_boolean(), svgfig.Path.parse_command(), and svgfig.Path.parse_number().

  def parse_whitespace(self, index, pathdata):
    """Part of Path's text-command parsing algorithm; used internally."""
    while index < len(pathdata) and pathdata[index] in (" ", "\t", "\r", "\n", ","): index += 1
    return index, pathdata

def svgfig.Path.SVG	(		self,
			trans = None
	)

Apply the transformation "trans" and return an SVG object.

Definition at line 1227 of file svgfig.py.

References svgfig.SVG.attr, svgfig.Path.attr, svgfig.Fig.d, svgfig.Plot.d, svgfig.Frame.d, svgfig.Path.d, join(), and svgfig.totrans().

  def SVG(self, trans=None):
    """Apply the transformation "trans" and return an SVG object."""
    if isinstance(trans, str): trans = totrans(trans)

    x, y, X, Y = None, None, None, None
    output = []
    for datum in self.d:
      if not isinstance(datum, (tuple, list)):
        raise TypeError("pathdata elements must be tuples/lists")

      command = datum[0]

      ######################
      if command in ("Z", "z"):
        x, y, X, Y = None, None, None, None
        output.append("Z")

      ######################
      elif command in ("H", "h", "V", "v"):
        command, num1 = datum

        if command == "H" or (command == "h" and x == None): x = num1
        elif command == "h": x += num1
        elif command == "V" or (command == "v" and y == None): y = num1
        elif command == "v": y += num1

        if trans == None: X, Y = x, y
        else: X, Y = trans(x, y)

        output.append("L%g %g" % (X, Y))
        
      ######################
      elif command in ("M", "m", "L", "l", "T", "t"):
        command, num1, num2, isglobal12 = datum

        if trans == None or isglobal12:
          if command.isupper() or X == None or Y == None:
            X, Y = num1, num2
          else:
            X += num1
            Y += num2
          x, y = X, Y

        else:
          if command.isupper() or x == None or y == None:
            x, y = num1, num2
          else:
            x += num1
            y += num2
          X, Y = trans(x, y)

        COMMAND = command.capitalize()
        output.append("%s%g %g" % (COMMAND, X, Y))

      ######################
      elif command in ("S", "s", "Q", "q"):
        command, num1, num2, isglobal12, num3, num4, isglobal34 = datum

        if trans == None or isglobal12:
          if command.isupper() or X == None or Y == None:
            CX, CY = num1, num2
          else:
            CX = X + num1
            CY = Y + num2

        else:
          if command.isupper() or x == None or y == None:
            cx, cy = num1, num2
          else:
            cx = x + num1
            cy = y + num2
          CX, CY = trans(cx, cy)

        if trans == None or isglobal34:
          if command.isupper() or X == None or Y == None:
            X, Y = num3, num4
          else:
            X += num3
            Y += num4
          x, y = X, Y

        else:
          if command.isupper() or x == None or y == None:
            x, y = num3, num4
          else:
            x += num3
            y += num4
          X, Y = trans(x, y)

        COMMAND = command.capitalize()
        output.append("%s%g %g %g %g" % (COMMAND, CX, CY, X, Y))

      ######################
      elif command in ("C", "c"):
        command, num1, num2, isglobal12, num3, num4, isglobal34, num5, num6, isglobal56 = datum

        if trans == None or isglobal12:
          if command.isupper() or X == None or Y == None:
            C1X, C1Y = num1, num2
          else:
            C1X = X + num1
            C1Y = Y + num2

        else:
          if command.isupper() or x == None or y == None:
            c1x, c1y = num1, num2
          else:
            c1x = x + num1
            c1y = y + num2
          C1X, C1Y = trans(c1x, c1y)

        if trans == None or isglobal34:
          if command.isupper() or X == None or Y == None:
            C2X, C2Y = num3, num4
          else:
            C2X = X + num3
            C2Y = Y + num4

        else:
          if command.isupper() or x == None or y == None:
            c2x, c2y = num3, num4
          else:
            c2x = x + num3
            c2y = y + num4
          C2X, C2Y = trans(c2x, c2y)

        if trans == None or isglobal56:
          if command.isupper() or X == None or Y == None:
            X, Y = num5, num6
          else:
            X += num5
            Y += num6
          x, y = X, Y

        else:
          if command.isupper() or x == None or y == None:
            x, y = num5, num6
          else:
            x += num5
            y += num6
          X, Y = trans(x, y)

        COMMAND = command.capitalize()
        output.append("%s%g %g %g %g %g %g" % (COMMAND, C1X, C1Y, C2X, C2Y, X, Y))

      ######################
      elif command in ("A", "a"):
        command, num1, num2, isglobal12, angle, large_arc_flag, sweep_flag, num3, num4, isglobal34 = datum

        oldx, oldy = x, y
        OLDX, OLDY = X, Y

        if trans == None or isglobal34:
          if command.isupper() or X == None or Y == None:
            X, Y = num3, num4
          else:
            X += num3
            Y += num4
          x, y = X, Y

        else:
          if command.isupper() or x == None or y == None:
            x, y = num3, num4
          else:
            x += num3
            y += num4
          X, Y = trans(x, y)
        
        if x != None and y != None:
          centerx, centery = (x + oldx)/2., (y + oldy)/2.
        CENTERX, CENTERY = (X + OLDX)/2., (Y + OLDY)/2.

        if trans == None or isglobal12:
          RX = CENTERX + num1
          RY = CENTERY + num2

        else:
          rx = centerx + num1
          ry = centery + num2
          RX, RY = trans(rx, ry)

        COMMAND = command.capitalize()
        output.append("%s%g %g %g %d %d %g %g" % (COMMAND, RX - CENTERX, RY - CENTERY, angle, large_arc_flag, sweep_flag, X, Y))

      elif command in (",", "."):
        command, num1, num2, isglobal12, angle, num3, num4, isglobal34 = datum
        if trans == None or isglobal34:
          if command == "." or X == None or Y == None:
            X, Y = num3, num4
          else:
            X += num3
            Y += num4
            x, y = None, None

        else:
          if command == "." or x == None or y == None:
            x, y = num3, num4
          else:
            x += num3
            y += num4
          X, Y = trans(x, y)

        if trans == None or isglobal12:
          RX = X + num1
          RY = Y + num2

        else:
          rx = x + num1
          ry = y + num2
          RX, RY = trans(rx, ry)

        RX, RY = RX - X, RY - Y

        X1, Y1 = X + RX * math.cos(angle*math.pi/180.), Y + RX * math.sin(angle*math.pi/180.)
        X2, Y2 = X + RY * math.sin(angle*math.pi/180.), Y - RY * math.cos(angle*math.pi/180.)
        X3, Y3 = X - RX * math.cos(angle*math.pi/180.), Y - RX * math.sin(angle*math.pi/180.)
        X4, Y4 = X - RY * math.sin(angle*math.pi/180.), Y + RY * math.cos(angle*math.pi/180.)

        output.append("M%g %gA%g %g %g 0 0 %g %gA%g %g %g 0 0 %g %gA%g %g %g 0 0 %g %gA%g %g %g 0 0 %g %g" \
                      % (X1, Y1, RX, RY, angle, X2, Y2, RX, RY, angle, X3, Y3, RX, RY, angle, X4, Y4, RX, RY, angle, X1, Y1))

    return SVG("path", d="".join(output), **self.attr)

Member Data Documentation

svgfig.Path.attr

Definition at line 1067 of file svgfig.py.

Referenced by svgfig.Path.__repr__(), svgfig.Curve.__repr__(), svgfig.Poly.__repr__(), svgfig.Text.__repr__(), svgfig.TextGlobal.__repr__(), svgfig.Dots.__repr__(), svgfig.Line.__repr__(), svgfig.LineGlobal.__repr__(), svgfig.VLine.__repr__(), svgfig.HLine.__repr__(), svgfig.Rect.__repr__(), svgfig.Ellipse.__repr__(), svgfig.Ticks.__repr__(), svgfig.CurveAxis.__repr__(), svgfig.LineAxis.__repr__(), svgfig.XAxis.__repr__(), svgfig.YAxis.__repr__(), svgfig.Axes.__repr__(), svgfig.HGrid.__repr__(), svgfig.VGrid.__repr__(), svgfig.Grid.__repr__(), svgfig.Curve.Path(), svgfig.Poly.Path(), svgfig.Rect.Path(), svgfig.Path.SVG(), svgfig.Text.SVG(), svgfig.TextGlobal.SVG(), svgfig.LineGlobal.SVG(), svgfig.Axes.SVG(), svgfig.XErrorBars.SVG(), and svgfig.YErrorBars.SVG().

svgfig.Path.d

Definition at line 1064 of file svgfig.py.

Referenced by svgfig.Path.__repr__(), svgfig.Poly.__repr__(), svgfig.Text.__repr__(), svgfig.TextGlobal.__repr__(), svgfig.Dots.__repr__(), svgfig.XErrorBars.__repr__(), svgfig.YErrorBars.__repr__(), svgfig.Poly.Path(), svgfig.Path.SVG(), svgfig.Text.SVG(), svgfig.TextGlobal.SVG(), svgfig.Dots.SVG(), svgfig.XErrorBars.SVG(), and svgfig.YErrorBars.SVG().

dictionary svgfig.Path.defaults = {}

static

Definition at line 1058 of file svgfig.py.

Referenced by tree.Tree.reset(), and tree.Tree.var().