#Copyright ReportLab Europe Ltd. 2000-2017 #see license.txt for license details __version__='3.4.34' __doc__='''Utility functions to position and resize boxes within boxes''' def rectCorner(x, y, width, height, anchor='sw', dims=False): '''given rectangle controlled by x,y width and height return the corner corresponding to the anchor''' if anchor not in ('nw','w','sw'): if anchor in ('n','c','s'): x += width/2. else: x += width if anchor not in ('sw','s','se'): if anchor in ('w','c','e'): y += height/2. else: y += height return (x,y,width,height) if dims else (x,y) def aspectRatioFix(preserve,anchor,x,y,width,height,imWidth,imHeight,anchorAtXY=False): """This function helps position an image within a box. It first normalizes for two cases: - if the width is None, it assumes imWidth - ditto for height - if width or height is negative, it adjusts x or y and makes them positive Given (a) the enclosing box (defined by x,y,width,height where x,y is the \ lower left corner) which you wish to position the image in, and (b) the image size (imWidth, imHeight), and (c) the 'anchor point' as a point of the compass - n,s,e,w,ne,se etc \ and c for centre, this should return the position at which the image should be drawn, as well as a scale factor indicating what scaling has happened. It returns the parameters which would be used to draw the image without any adjustments: x,y, width, height, scale used in canvas.drawImage and drawInlineImage """ scale = 1.0 if width is None: width = imWidth if height is None: height = imHeight if width<0: width = -width x -= width if height<0: height = -height y -= height if preserve: imWidth = abs(imWidth) imHeight = abs(imHeight) scale = min(width/float(imWidth),height/float(imHeight)) owidth = width oheight = height width = scale*imWidth-1e-8 height = scale*imHeight-1e-8 if not anchorAtXY: # if anchor not in ('nw','w','sw'): # dx = owidth-width # if anchor in ('n','c','s'): # x += dx/2. # else: # x += dx # if anchor not in ('sw','s','se'): # dy = oheight-height # if anchor in ('w','c','e'): # y += dy/2. # else: # y += dy x, y = rectCorner(x,y,owidth-width,oheight-height,anchor) if anchorAtXY: if anchor not in ('sw','s','se'): y -= height/2. if anchor in ('e','c','w') else height if anchor not in ('nw','w','sw'): x -= width/2. if anchor in ('n','c','s') else width return x,y, width, height, scale