/*------------------------------------------------
Display large digits (18 x 28 pixels) on the NXT screen by techbricks.nl
two row, each row 4 digits, range: .0001 ... 9999
24 september 2009
NXC, build on NXC/NBC firmware version 1.28, Bricxcc 3.3 - build 3.3.7.20
Check http://bricxcc.sourceforge.net/nbc/ for more info abou NXC
Read more about it at www.techbricks.nl/My-NXT-projects/nxttachometerspeedcomputer.html

Use this demo program to display digits for your own applications....
-------------------------------------------------*/

// variable declaration
int row,value,len_string,current,oldest;
int decimal_point,current_position,point_position,start_position,end_position;
int digit,current_digit,shift_x,shift_y;
string sdiget,svalue,szeros;
bool bit[10][8];
int shift_x_digit[5],shift_y_digit[5];


/*---------------------------------------------------
This function draws the digit on the NXT display
x_position is the horizontal position (digit 1,2,3 or 4)
y_positopn is the virtical position (row 1 or 2)
----------------------------------------------------*/
void DisplayDigit(int digit, int position_x, int position_y)
{
 // shift digit to the disired position
 shift_x=shift_x_digit[position_x];
 shift_y=shift_y_digit[position_y];

 /*---------- Construction of the digits -----
 The digits are made of 7 bits

 --1--
|     |
2     3
|--4--|
5     6
|     |
 --7--

--------------------*/

  // display the first bit
  if (bit[digit][1]==true)
    {
     LineOut(1+shift_x,60-shift_y,16+shift_x,60-shift_y);
     LineOut(2+shift_x,59-shift_y,15+shift_x,59-shift_y);
     LineOut(3+shift_x,58-shift_y,14+shift_x,58-shift_y);
    }
  // display the second bit
  if (bit[digit][2]==true)
    {
     LineOut(0+shift_x,58-shift_y,0+shift_x,48-shift_y);
     LineOut(1+shift_x,57-shift_y,1+shift_x,49-shift_y);
     LineOut(2+shift_x,56-shift_y,2+shift_x,50-shift_y);
    }
    // display the thirt bit
  if (bit[digit][3]==true)
    {
     LineOut(17+shift_x,58-shift_y,17+shift_x,48-shift_y);
     LineOut(16+shift_x,57-shift_y,16+shift_x,49-shift_y);
     LineOut(15+shift_x,56-shift_y,15+shift_x,50-shift_y);
    }
  // display the fourth bit
  if (bit[digit][4]==true)
    {
     LineOut(2+shift_x,47-shift_y,15+shift_x,47-shift_y);
     LineOut(1+shift_x,46-shift_y,16+shift_x,46-shift_y);
     LineOut(2+shift_x,45-shift_y,15+shift_x,45-shift_y);
    }
  // display the fifth bit
  if (bit[digit][5]==true)
    {
     LineOut(0+shift_x,44-shift_y,0+shift_x,34-shift_y);
     LineOut(1+shift_x,43-shift_y,1+shift_x,35-shift_y);
     LineOut(2+shift_x,42-shift_y,2+shift_x,36-shift_y);
    }
  // display the sixth bit
  if (bit[digit][6]==true)
    {
     LineOut(17+shift_x,44-shift_y,17+shift_x,34-shift_y);
     LineOut(16+shift_x,43-shift_y,16+shift_x,35-shift_y);
     LineOut(15+shift_x,42-shift_y,15+shift_x,36-shift_y);
    }
  // display the seventh bit
  if (bit[digit][7]==true)
    {
     LineOut(3+shift_x,34-shift_y,14+shift_x,34-shift_y);
     LineOut(2+shift_x,33-shift_y,15+shift_x,33-shift_y);
     LineOut(1+shift_x,32-shift_y,16+shift_x,32-shift_y);
    }

}

/*--------------------------------------------------------
This function does the initializing of the figures
---------------------------------------------------------*/
void DisplayInitiation()
{
// digit 0 - bit 1,2,3,5,6,7
 bit[0][1]=true;   //   _
 bit[0][2]=true;   //  | |
 bit[0][3]=true;   //  |_|
 bit[0][4]=false;
 bit[0][5]=true;
 bit[0][6]=true;
 bit[0][7]=true;

 // digit 1 - bit 3,6
 bit[1][1]=false;   //  |
 bit[1][2]=false;   //  |
 bit[1][3]=true;
 bit[1][4]=false;
 bit[1][5]=false;
 bit[1][6]=true;
 bit[1][7]=false;

 // digit 2 - bit 1,3,4,5,7
 bit[2][1]=true;    //  _
 bit[3][2]=false;   //  _|
 bit[2][3]=true;    // |_
 bit[2][4]=true;
 bit[2][5]=true;
 bit[2][6]=false;
 bit[2][7]=true;

 // digit 3 - bit 1,3,4,6,7
 bit[3][1]=true;    //  _
 bit[3][2]=false;   //  _|
 bit[3][3]=true;    //  _|
 bit[3][4]=true;
 bit[3][5]=false;
 bit[3][6]=true;
 bit[3][7]=true;

 // digit 4 - bit 2,3,4,6
 bit[4][1]=false;   //
 bit[4][2]=true;    //  |_|
 bit[4][3]=true;    //    |
 bit[4][4]=true;
 bit[4][5]=false;
 bit[4][6]=true;
 bit[4][7]=false;

 // digit 5 - bit 1,2,4,6,7
 bit[5][1]=true;     //   _
 bit[5][2]=true;     //  |_
 bit[5][3]=false;    //   _|
 bit[5][4]=true;
 bit[5][5]=false;
 bit[5][6]=true;
 bit[5][7]=true;

 // digit 6 - bit 1,2,4,5,6,7
 bit[6][1]=true;      //   _
 bit[6][2]=true;      //  |_
 bit[6][3]=false;     //  |_|
 bit[6][4]=true;
 bit[6][5]=true;
 bit[6][6]=true;
 bit[6][7]=true;

 // digit 7 - bit 1,3,6
 bit[7][1]=true;      //   _
 bit[7][2]=false;     //    |
 bit[7][3]=true;      //    |
 bit[7][4]=false;
 bit[7][5]=false;
 bit[7][6]=true;
 bit[7][7]=false;

 // digit 8 - bit 1,2,3,4,5,6,7
 bit[8][1]=true;       //   _
 bit[8][2]=true;       //  |_|
 bit[8][3]=true;       //  |_|
 bit[8][4]=true;
 bit[8][5]=true;
 bit[8][6]=true;
 bit[8][7]=true;

 // digit 9 - bit 1,2,3,4,6,7
 bit[9][1]=true;       //   _
 bit[9][2]=true;       //  |_|
 bit[9][3]=true;       //   _|
 bit[9][4]=true;
 bit[9][5]=false;
 bit[9][6]=true;
 bit[9][7]=true;

 // this specifices how many pixels to shift horizontal for the next digits
 shift_x_digit[1]=7;
 shift_x_digit[2]=32;
 shift_x_digit[3]=55;
 shift_x_digit[4]=80;

 // this specifices how many pixels to shift virtical for the next line
 shift_y_digit[1]=-1;
 shift_y_digit[2]=31;

   // clear the NXT display
   ClearScreen();

}

/*--------------------------------------------------------
This function displayd the digits and decimal point on the correct row
---------------------------------------------------------*/
void DisplayNumber(int value,int decimal_point,int row)
{
  if (row<1) row=1;
   if (row>2) row=2;
   if (decimal_point<0) decimal_point=0;
   if (decimal_point>6) decimal_point=6;

   // transform integer to string and determine the lenght.
   svalue=NumToStr(value);
   len_string=StrLen(svalue);

   if ((len_string-decimal_point)>4)
     {
      svalue="9999";
      len_string=4;
      decimal_point=0;
     }
   else
     {
      if ((len_string-decimal_point)<-3)
        {
        svalue="0000";
        len_string=4;
        decimal_point=0;
        }
      else
        {
        if ((len_string-decimal_point)<1)
          {
          szeros=SubStr("0000",1,(1+decimal_point-len_string));
          svalue=StrCat(szeros,svalue);
          len_string=StrLen(svalue);
          decimal_point=decimal_point-len_string;
          if (len_string>4)
            {
             len_string=4;
            }
          decimal_point=decimal_point+len_string;
          }
        }
      }

   // Determine most right displayed digit.
   if (len_string>4)
      {
       decimal_point=decimal_point-(len_string-4);
       len_string=4;
      }

   // Determine most left digit position.
   start_position=5-len_string;


   current_position=1;
   while (current_position<=len_string)
      {
      // get sub string
      sdiget=SubStr(svalue,current_position-1,1);
      current_digit=StrToNum(sdiget);
      // display digit
      DisplayDigit(current_digit,(start_position+current_position-1),row);
      current_position=current_position+1;
      }
   point_position=4-decimal_point;
   if ((point_position>=0)&&(point_position<4))
     {
      CircleOut(shift_x_digit[point_position+1]-4, 33-shift_y_digit[row], 1);
      CircleOut(shift_x_digit[point_position+1]-4, 33-shift_y_digit[row], 2);
     }
}


task main()
{

   DisplayInitiation();
while (true)
  {
   ClearScreen();
   // Set these values:
   value=Random(10000);       //value to be displayed on the NXT screen, can 4 digits
   row=1;                     //row on the NXT screen, can be 1 or 2
   decimal_point=Random(6);   //amount of figures on the right side of the decimal point, can be between 0 and 5
   // Display Number on NXT screen
   DisplayNumber(value,decimal_point,row);

   value=Random(10000);       //value to be displayed on the NXT screen, can 4 digits
   row=2;                     //row on the NXT screen, can be 1 or 2
   decimal_point=Random(6);   //amount of figures on the right side of the decimal point, can be between 0 and 5
   // Display Number on NXT screen
   DisplayNumber(value,decimal_point,row);

   Wait(1000);
  }
}