Source Code for Module Task.Tools.Utils

  1  ''' 
  2  Defines L{Tools} that function as a set of utilities. 
  3   
  4  @author: Brett Clippingdale 
  5  @author: Peter Parente 
  6  @organization: IBM Corporation 
  7  @copyright: Copyright (c) 2005, 2007 IBM Corporation 
  8  @license: The BSD License 
  9   
 10  All rights reserved. This program and the accompanying materials are made  
 11  available under the terms of the BSD license which accompanies 
 12  this distribution, and is available at 
 13  U{http://www.opensource.org/licenses/bsd-license.php} 
 14  ''' 
 15   
 16  import Base, AEConstants 
 17   
 18 -class Utils(Base.TaskTools): 
 19    ''' 
 20    Provides utility methods that assist L{Perk} developers in processing  
 21    accessibility information, but do not touch accessible objects, do output, 
 22    handle input, manage the LSR system, etc. 
 23    ''' 
 24 -  def getColorString(self, val): 
 25      ''' 
 26      Tries to map a given RGB string (if in form "u,u,u") to a nearby color  
 27      name. 
 28       
 29      @param val: Representation of an RGB color in form "u,u,u" 
 30      @type val: string 
 31      @return: Localized color name if val param is valid format, otherwise None 
 32      @rtype: string 
 33      ''' 
 34      # if color value an RGB 3-tuple, map it to a string value 
 35      try: 
 36        r, g, b = val.split(',') 
 37        r, g, b = int(r), int(g), int(b) 
 38      except (ValueError, TypeError, AttributeError): 
 39        return val 
 40      WORD = 256 # 8-bit word size 
 41       
 42      VISIBLE = 64 
 43      LOW_COLORATION = 4  
 44      LOW_SATURATION = 192 
 45      HIGH_SATURATION = 240 
 46       
 47      # normalize values into three 8-bit values to reprent RGB color 
 48      if r >= WORD or g >= WORD or b >= WORD: 
 49        r = int(r / WORD) # can't guarantee apps will have modulo 256 color 
 50        g = int(g / WORD) 
 51        b = int(b / WORD) 
 52       
 53      # if all values of RGB 3-tuple have low saturation, amplify them 
 54      while r < VISIBLE and g < VISIBLE and b < VISIBLE and \ 
 55            (r > LOW_COLORATION or g > LOW_COLORATION or b > LOW_COLORATION): 
 56        r = r << 1 
 57        g = g << 1 
 58        b = b << 1 
 59         
 60      # attenuation algo #1   
 61      ## if all values of RGB 3-tuple have high saturation, attenuate them 
 62      #while r >= LOW_SATURATION and g >= LOW_SATURATION and b >= LOW_SATURATION and \ 
 63            #(r < HIGH_SATURATION or g < HIGH_SATURATION or b < HIGH_SATURATION): 
 64        #print "high saturation: shifting rgb from:", r, g, b 
 65        #r = r >> 1 
 66        #g = g >> 1 
 67        #b = b >> 1 
 68        #print "shifted rgb to:" , r, g, b 
 69       
 70      # attenuation algo #2 
 71      # if all values of RGB 3-tuple have high saturation, attenuate them 
 72      if r >= LOW_SATURATION and g >= LOW_SATURATION and b >= LOW_SATURATION and \ 
 73         (r < HIGH_SATURATION or g < HIGH_SATURATION or b < HIGH_SATURATION): 
 74        if r < g and r < b: 
 75          r = r - 64 
 76        elif g < r and g < b: 
 77          g = g - 64 
 78        elif b < r and b < g: 
 79          b = b - 64 
 80        elif r == g == b: 
 81          # assign levels of grey based on saturation 
 82          if r > 250: 
 83            return AEConstants.COLOR_MAP[63] #'white' 
 84          elif r > 200: 
 85            return AEConstants.COLOR_MAP[41] # light grey 
 86          elif r > 96: 
 87            return AEConstants.COLOR_MAP[21] # medium grey 
 88          else: 
 89            return AEConstants.COLOR_MAP[42] # dark grey 
 90          pass 
 91        elif r == g: 
 92          r = r - 64 
 93          g = g - 64 
 94        elif r == b: 
 95          r = r - 64 
 96          b = b - 64 
 97        elif g == b: 
 98          g = g - 64 
 99          b = b - 64 
100         
101      # place high 2-bits of each color into bitfield: rrggbb for value 0..63 
102      r = r >> 6 << 4 
103      g = g >> 6 << 2 
104      b = b >> 6 
105      rgb = r+g+b # add into 6-bit bitfield (rrggbb) for integer value 0..63 
106      name = AEConstants.COLOR_MAP[rgb] # get the color value from dictionary 
107      return name 
108     
109 -  def convertPOSIXToIANA(self, lang): 
110      ''' 
111      Converts a POSIX language string to a IANA language tag following RFC 4646 
112      U{http://www.ietf.org/rfc/rfc4646.txt}, the format recommended for  
113      L{AEOutput} device language settings. 
114       
115      The POSIX format is language[_territory][.codeset] 
116       
117      Some examples include "en", "fr_CA", "en_US.UTF-8". Ambiguous conversions  
118      such as "zh_CN" are allowed, but do not pinpoint specific spoken dialects  
119      (i.e. Mandarin, Cantonese, Pinyin, Taiwanese Mandarin, etc.) The code set 
120      is currently ignored, though may serve as a hint for the dialect in the 
121      future. 
122   
123      @param lang: POSIX locale string 
124      @type lang: string 
125      @return: IANA language tag 
126      @rtype: string 
127      ''' 
128      tag = [] 
129      lang = lang.split('_') 
130      try: 
131        # if first element is there, it's the language code 
132        tag.append(lang[0]) 
133      except IndexError: 
134        pass 
135      try: 
136        # if the second element is there, it's the territory code 
137        t = lang[1].split('.')[0] 
138      except IndexError: 
139        pass 
140      else: 
141        # if there was no language code, backfill using the territory 
142        if len(tag) == 0: 
143          tag.append(t) 
144        tag.append(t)  
145      # make lowercase for comparison 
146      return '-'.join(tag).lower() 
147