# $Id$ # based upon # piddle.py -- Plug In Drawing, Does Little Else # Copyright (C) 1999 Joseph J. Strout # # This library is free software; you can redistribute it and/or # modify it under the terms of the GNU Lesser General Public # License as published by the Free Software Foundation; either # version 2 of the License, or (at your option) any later version. # # This library is distributed in the hope that it will be useful, # but WITHOUT ANY WARRANTY; without even the implied warranty of # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU # Lesser General Public License for more details. # # You should have received a copy of the GNU Lesser General Public # License along with this library; if not, write to the Free Software # Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA # Progress Reports... # JJS, 2/10/99: as discussed, I've removed the Shape classes and moved # the drawing methods into the Canvas class. Numerous other changes # as discussed by email as well. # JJS, 2/11/99: removed Canvas default access functions; added fontHeight # etc. functions; fixed numerous typos; added drawRect and drawRoundRect # (how could I forget those?). Added StateSaver utility class. # 2/11/99 (later): minor fixes. # JJS, 2/12/99: removed scaling/sizing references. Changed event handler # mechanism per Magnus's idea. Changed drawCurve into a fillable # drawing function (needs default implementation). Removed edgeList # from drawPolygon. Added drawFigure. Changed drawLines to draw # a set of disconnected lines (of uniform color and width). # 2/12/99 (later): added HexColor function and WWW color constants. # Fixed bug in StateSaver. Changed params to drawArc. # JJS, 2/17/99: added operator methods to Color; added default implementation # of drawRoundRect in terms of Line, Rect, and Arc. # JJS, 2/18/99: added isInteractive and canUpdate methods to Canvas. # JJS, 2/19/99: added drawImage method; added angle parameter to drawString. # JJS, 3/01/99: nailed down drawFigure interface (and added needed constants). # JJS, 3/08/99: added arcPoints and curvePoints methods; added default # implementations for drawRect, drawRoundRect, drawArc, drawCurve, # drawEllipse, and drawFigure (!), mostly thanks to Magnus. # JJS, 3/09/99: added 'closed' parameter to drawPolygon, drawCurve, and # drawFigure. Made use of this in several default implementations. # JJS, 3/11/99: added 'onKey' callback and associated constants; also added # Canvas.setInfoLine(s) method. # JJS, 3/12/99: typo in drawFigure.__doc__ corrected (thanks to Magnus). # JJS, 3/19/99: fixed bug in drawArc (also thanks to Magnus). # JJS, 5/30/99: fixed bug in arcPoints. # JJS, 6/10/99: added __repr__ method to Font. # JJS, 6/22/99: added additional WWW colors thanks to Rafal Smotrzyk # JJS, 6/29/99: added inch and cm units # JJS, 6/30/99: added size & name parameters to Canvas.__init__ # JJS, 9/21/99: fixed bug in arcPoints # JJS, 9/29/99: added drawMultiLineStrings, updated fontHeight with new definition # JJS, 10/21/99: made Color immutable; fixed bugs in default fontHeight, # drawMultiLineString """ PIDDLE (Plug-In Drawing, Does Little Else) 2D Plug-In Drawing System Magnus Lie Hetland Andy Robinson Joseph J. Strout and others February-March 1999 On coordinates: units are Big Points, approximately 1/72 inch. The origin is at the top-left, and coordinates increase down (y) and to the right (x). """ __version_maj_number__ = "1.0" # if release should match "1.0" __version_min_number__ = "0" # should match "12" __version__ = __version_maj_number__ + "." + __version_min_number__ # c.f. "1.0.12" from rdkit.sping.colors import * inch = 72 # 1 PIDDLE drawing unit == 1/72 imperial inch cm = inch/2.54 # more sensible measurement unit #------------------------------------------------------------------------- # StateSaver #------------------------------------------------------------------------- class StateSaver: """This is a little utility class for saving and restoring the default drawing parameters of a canvas. To use it, add a line like this before changing any of the parameters: saver = StateSaver(myCanvas) then, when "saver" goes out of scope, it will automagically restore the drawing parameters of myCanvas.""" def __init__(self, canvas): self.canvas = canvas self.defaultLineColor = canvas.defaultLineColor self.defaultFillColor = canvas.defaultFillColor self.defaultLineWidth = canvas.defaultLineWidth self.defaultFont = canvas.defaultFont def __del__(self): self.canvas.defaultLineColor = self.defaultLineColor self.canvas.defaultFillColor = self.defaultFillColor self.canvas.defaultLineWidth = self.defaultLineWidth self.canvas.defaultFont = self.defaultFont #------------------------------------------------------------------------- # Font #------------------------------------------------------------------------- class Font: "This class represents font typeface, size, and style." def __init__(self, size=12, bold=0, italic=0, underline=0, face=None): # public mode variables d = self.__dict__ d["bold"] = bold d["italic"] = italic d["underline"] = underline # public font size (points) d["size"] = size # typeface -- a name or set of names, interpreted by the Canvas, # or "None" to indicate the Canvas-specific default typeface d["face"] = face def __cmp__(self, other): """Compare two fonts to see if they're the same.""" if self.face == other.face and self.size == other.size and \ self.bold == other.bold and self.italic == other.italic \ and self.underline == other.underline: return 0 else: return 1 def __repr__(self): return "Font(%d,%d,%d,%d,%s)" % (self.size, self.bold, self.italic, \ self.underline, repr(self.face)) def __setattr__(self, name, value): raise TypeError("piddle.Font has read-only attributes") #------------------------------------------------------------------------- # constants needed for Canvas.drawFigure #------------------------------------------------------------------------- figureLine = 1 figureArc = 2 figureCurve = 3 #------------------------------------------------------------------------- # key constants used for special keys in the onKey callback #------------------------------------------------------------------------- keyBksp = '\010' # (erases char to left of cursor) keyDel = '\177' # (erases char to right of cursor) keyLeft = '\034' keyRight = '\035' keyUp = '\036' keyDown = '\037' keyPgUp = '\013' keyPgDn = '\014' keyHome = '\001' keyEnd = '\004' keyClear = '\033' keyTab = '\t' modShift = 1 # shift key was also held modControl = 2 # control key was also held #------------------------------------------------------------------------- # Canvas #------------------------------------------------------------------------- class Canvas: """This is the base class for a drawing canvas. The 'plug-in renderers' we speak of are really just classes derived from this one, which implement the various drawing methods.""" def __init__(self, size=(300,300), name="PIDDLE"): """Initialize the canvas, and set default drawing parameters. Derived classes should be sure to call this method.""" # defaults used when drawing self.defaultLineColor = black self.defaultFillColor = transparent self.defaultLineWidth = 1 self.defaultFont = Font() # set up null event handlers # onClick: x,y is Canvas coordinates of mouseclick def ignoreClick(canvas,x,y): pass self.onClick = ignoreClick # onOver: x,y is Canvas location of mouse def ignoreOver(canvas,x,y): pass self.onOver = ignoreOver # onKey: key is printable character or one of the constants above; # modifiers is a tuple containing any of (modShift, modControl) def ignoreKey(canvas,key,modifiers): pass self.onKey = ignoreKey # size and name, for user's reference self.size, self.name = size,name def getSize(self): # gL return self.size #------------ canvas capabilities ------------- def isInteractive(self): "Returns 1 if onClick, onOver, and onKey events are possible, 0 otherwise." return 0 def canUpdate(self): "Returns 1 if the drawing can be meaningfully updated over time \ (e.g., screen graphics), 0 otherwise (e.g., drawing to a file)." return 0 #------------ general management ------------- def clear(self): "Call this to clear and reset the graphics context." pass def flush(self): "Call this to indicate that any comamnds that have been issued \ but which might be buffered should be flushed to the screen" pass def save(self, file=None, format=None): """For backends that can be save to a file or sent to a stream, create a valid file out of what's currently been drawn on the canvas. Trigger any finalization here. Though some backends may allow further drawing after this call, presume that this is not possible for maximum portability file may be either a string or a file object with a write method if left as the default, the canvas's current name will be used format may be used to specify the type of file format to use as well as any corresponding extension to use for the filename This is an optional argument and backends may ignore it if they only produce one file format.""" pass def setInfoLine(self, s): "For interactive Canvases, displays the given string in the \ 'info line' somewhere where the user can probably see it." pass #------------ string/font info ------------ def stringBox(self,s,font=None): return self.stringWidth(s,font),self.fontHeight(font) def stringWidth(self, s, font=None): "Return the logical width of the string if it were drawn \ in the current font (defaults to self.font)." raise NotImplementedError('stringWidth') def fontHeight(self, font=None): "Find the height of one line of text (baseline to baseline) of the given font." # the following approxmation is correct for PostScript fonts, # and should be close for most others: if not font: font = self.defaultFont return 1.2 * font.size def fontAscent(self, font=None): "Find the ascent (height above base) of the given font." raise NotImplementedError('fontAscent') def fontDescent(self, font=None): "Find the descent (extent below base) of the given font." raise NotImplementedError('fontDescent') #------------- drawing helpers -------------- def arcPoints(self, x1,y1, x2,y2, startAng=0, extent=360): "Return a list of points approximating the given arc." # Note: this implementation is simple and not particularly efficient. xScale = abs((x2-x1)/2.0) yScale = abs((y2-y1)/2.0) x = min(x1,x2)+xScale y = min(y1,y2)+yScale # "Guesstimate" a proper number of points for the arc: steps = min(max(xScale,yScale)*(extent/10.0)/10,200) if steps < 5: steps = 5 from math import sin, cos, pi pointlist = [] step = float(extent)/steps angle = startAng for i in range(int(steps+1)): point = (x+xScale*cos((angle/180.0)*pi), y-yScale*sin((angle/180.0)*pi)) pointlist.append(point) angle = angle+step return pointlist def curvePoints(self, x1, y1, x2, y2, x3, y3, x4, y4): "Return a list of points approximating the given Bezier curve." # Adapted from BEZGEN3.HTML, one of the many # Bezier utilities found on Don Lancaster's Guru's Lair at # bezierSteps = min(max(max(x1,x2,x3,x4)-min(x1,x2,x3,x3), max(y1,y2,y3,y4)-min(y1,y2,y3,y4)), 200) dt1 = 1. / bezierSteps dt2 = dt1 * dt1 dt3 = dt2 * dt1 xx = x1 yy = y1 ux = uy = vx = vy = 0 ax = x4 - 3*x3 + 3*x2 - x1 ay = y4 - 3*y3 + 3*y2 - y1 bx = 3*x3 - 6*x2 + 3*x1 by = 3*y3 - 6*y2 + 3*y1 cx = 3*x2 - 3*x1 cy = 3*y2 - 3*y1 mx1 = ax * dt3 my1 = ay * dt3 lx1 = bx * dt2 ly1 = by * dt2 kx = mx1 + lx1 + cx*dt1 ky = my1 + ly1 + cy*dt1 mx = 6*mx1 my = 6*my1 lx = mx + 2*lx1 ly = my + 2*ly1 pointList = [(xx, yy)] for i in range(bezierSteps): xx = xx + ux + kx yy = yy + uy + ky ux = ux + vx + lx uy = uy + vy + ly vx = vx + mx vy = vy + my pointList.append((xx, yy)) return pointList def drawMultiLineString(self, s, x,y, font=None, color=None, angle=0, **kwargs): "Breaks string into lines (on \n, \r, \n\r, or \r\n), and calls drawString on each." import math import string h = self.fontHeight(font) dy = h * math.cos(angle*math.pi/180.0) dx = h * math.sin(angle*math.pi/180.0) s = string.replace(s, '\r\n', '\n') s = string.replace(s, '\n\r', '\n') s = string.replace(s, '\r', '\n') lines = string.split(s, '\n') for line in lines: self.drawString(line, x, y, font, color, angle) x = x + dx y = y + dy #------------- drawing methods -------------- # Note default parameters "=None" means use the defaults # set in the Canvas method: defaultLineColor, etc. def drawLine(self, x1,y1, x2,y2, color=None, width=None, dash=None, **kwargs): "Draw a straight line between x1,y1 and x2,y2." raise NotImplementedError('drawLine') def drawLines(self, lineList, color=None, width=None, dash=None, **kwargs): "Draw a set of lines of uniform color and width. \ lineList: a list of (x1,y1,x2,y2) line coordinates." # default implementation: for x1, y1, x2, y2 in lineList: self.drawLine(x1, y1, x2, y2 ,color,width, dash=dash,**kwargs) # For text, color defaults to self.lineColor. def drawString(self, s, x,y, font=None, color=None, angle=0, **kwargs): "Draw a string starting at location x,y." # NOTE: the baseline goes on y; drawing covers (y-ascent,y+descent) raise NotImplementedError('drawString') # For fillable shapes, edgeColor defaults to self.defaultLineColor, # edgeWidth defaults to self.defaultLineWidth, and # fillColor defaults to self.defaultFillColor. # Specify "don't fill" by passing fillColor=transparent. def drawCurve(self, x1,y1, x2,y2, x3,y3, x4,y4, edgeColor=None, edgeWidth=None, fillColor=None, closed=0, dash=None,**kwargs): "Draw a Bezier curve with control points x1,y1 to x4,y4." pointlist = self.curvePoints(x1, y1, x2, y2, x3, y3, x4, y4) self.drawPolygon(pointlist, edgeColor=edgeColor, edgeWidth=edgeWidth, fillColor=fillColor, closed=closed,dash=dash, **kwargs) def drawRect(self, x1,y1, x2,y2, edgeColor=None, edgeWidth=None, fillColor=None, dash=None, **kwargs): "Draw the rectangle between x1,y1, and x2,y2. \ These should have x10, and ry>0." x1, x2 = min(x1,x2), max(x1, x2) y1, y2 = min(y1,y2), max(y1, y2) dx = rx*2 dy = ry*2 partList = [ (figureArc, x1, y1, x1+dx, y1+dy, 180, -90), (figureLine, x1+rx, y1, x2-rx, y1), (figureArc, x2-dx, y1, x2, y1+dy, 90, -90), (figureLine, x2, y1+ry, x2, y2-ry), (figureArc, x2-dx, y2, x2, y2-dy, 0, -90), (figureLine, x2-rx, y2, x1+rx, y2), (figureArc, x1, y2, x1+dx, y2-dy, -90, -90), (figureLine, x1, y2-ry, x1, y1+rx) ] self.drawFigure(partList, edgeColor, edgeWidth, fillColor, closed=1, dash=dash, **kwargs) def drawEllipse(self, x1,y1, x2,y2, edgeColor=None, edgeWidth=None, fillColor=None,dash=None,**kwargs): "Draw an orthogonal ellipse inscribed within the rectangle x1,y1,x2,y2. \ These should have x1