src/freenet/captcha/alternatecaptcha1.cpp

   1 #include "../../../include/freenet/captcha/alternatecaptcha1.h"\r
   2 \r
   3 #include <cmath>\r
   4 \r
   5 #ifdef ALTERNATE_CAPTCHA\r
   6 \r
   7 AlternateCaptcha1::AlternateCaptcha1()\r
   8 {\r
   9         AlternateCaptchaFonts fonts;\r
  10         m_fonts=fonts.Fonts();\r
  11 }\r
  12 \r
  13 void AlternateCaptcha1::Generate()\r
  14 {\r
  15         std::string puzzlestring=GenerateRandomString(5);\r
  16         FreeImage::Bitmap tempchar(50,50,32);\r
  17         tempchar.SetTransparent();\r
  18         FreeImage::Bitmap bmp(110,50,32);\r
  19         bmp.SetTransparent();\r
  20 \r
  21         m_solution.clear();\r
  22         m_puzzle.clear();\r
  23 \r
  24         // draw the text\r
  25         if(m_fonts.size()>0)\r
  26         {\r
  27                 for(int i=0; i<puzzlestring.size(); i++)\r
  28                 {\r
  29                         RGBQUAD black;\r
  30                         black.rgbRed=0;\r
  31                         black.rgbGreen=0;\r
  32                         black.rgbBlue=0;\r
  33                         int xoffset=(i*20)-(5+(rand()%5));\r
  34                         int yoffset=(rand()%20)-10;\r
  35                         int fontnum=rand()%m_fonts.size();\r
  36                         FreeImage::Bitmap charbmp=m_fonts[fontnum].Char(puzzlestring[i]);\r
  37 \r
  38                         tempchar.SetTransparent();\r
  39                         tempchar.ClearTransparent();\r
  40                         tempchar.BlitTrans(charbmp,25-(charbmp.Width()/2),25-(charbmp.Height()/2),0,0,charbmp.Width(),charbmp.Height());\r
  41                         tempchar.Rotate((rand()%60)-30,0,0,25,25);\r
  42 \r
  43                         bmp.BlitTrans(tempchar,xoffset,yoffset,0,0,50,50);\r
  44                 }\r
  45         }\r
  46 \r
  47         //place some random lines\r
  48         RGBQUAD white;\r
  49         white.rgbRed=255;\r
  50         white.rgbGreen=255;\r
  51         white.rgbBlue=255;\r
  52         white.rgbReserved=255;\r
  53         int numlines=(rand()%5)+10;\r
  54         for(int i=0; i<numlines; i++)\r
  55         {\r
  56                 // draw 4 short lines very close to each other\r
  57                 int x1[4];\r
  58                 int y1[4];\r
  59                 int x2[4];\r
  60                 int y2[4];\r
  61 \r
  62                 x1[0]=rand()%bmp.Width();\r
  63                 y1[0]=rand()%bmp.Height();\r
  64                 x2[0]=x1[0]+(rand()%40)-20;\r
  65                 y2[0]=y1[0]+(rand()%40)-20;\r
  66 \r
  67                 for(int i=1; i<4; i++)\r
  68                 {\r
  69                         x1[i]=x1[i-1]+rand()%3-1;\r
  70                         y1[i]=y1[i-1]+rand()%3-1;\r
  71                         x2[i]=x2[i-1]+rand()%3-1;\r
  72                         y2[i]=y2[i-1]+rand()%3-1;\r
  73                 }\r
  74 \r
  75                 for(int i=0; i<4; i++)\r
  76                 {\r
  77                         bmp.Line(x1[i],y1[i],x2[i],y2[i],white);\r
  78                 }\r
  79         }\r
  80 \r
  81         // make output a little wavy\r
  82         int offset=rand()%10000;\r
  83         for(int y=0; y<bmp.Height(); y++)\r
  84         {\r
  85                 double shift=sin((double)(y+offset)/3.0);\r
  86                 bmp.HorizontalOffset(y,shift);\r
  87         }\r
  88 \r
  89         m_solution.clear();\r
  90         m_solution.insert(m_solution.end(),puzzlestring.begin(),puzzlestring.end());\r
  91         m_puzzle.clear();\r
  92         bmp.SaveToMemory("bmp",m_puzzle);\r
  93 \r
  94 }\r
  95 \r
  96 const std::string AlternateCaptcha1::GenerateRandomString(const int len)\r
  97 {\r
  98         // no l,1 O,0 because they look too much alike\r
  99         static std::string chars="abcdefghijkmnopqrstuvwxyzABCDEFGHIJKLMNPQRSTUVWXYZ23456789@#";\r
 100         std::string temp="";\r
 101         for(int i=0; i<len; i++)\r
 102         {\r
 103                 temp+=chars[rand()%chars.size()];\r
 104         }\r
 105         return temp;\r
 106 }\r
 107 \r
 108 const bool AlternateCaptcha1::GetPuzzle(std::vector<unsigned char> &puzzle)\r
 109 {\r
 110         puzzle=m_puzzle;\r
 111         return true;\r
 112 }\r
 113 \r
 114 const bool AlternateCaptcha1::GetSolution(std::vector<unsigned char> &solution)\r
 115 {\r
 116         solution=m_solution;\r
 117         return true;\r
 118 }\r
 119 \r
 120 #endif  // ALTERNATE_CAPTCHA\r