Нарисовать с помощью события OnPaint график функции y=cos x

#include <math>
void __fastcall TForm1::FormPaint(TObject *Sender)
{
TColor clContour        = clBlue,
       clWalls          = clDkGray,
       clBackGroundCity = clBlack,
       clWindowCity     = clYellow;
 
this->Canvas->Pen->Color   = clContour;
this->Canvas->Brush->Color = clBackGroundCity;
this->Canvas->FillRect( this->Canvas->ClipRect );
 
unsigned T         = 10,
         Amplitude = 100;
 
 
randomize();
for( unsigned Street=1, MaxStreet=10; Street<MaxStreet; Street++ )
  {
  unsigned Shift = random( T*Amplitude*Street );
  unsigned CurrStreet = this->Height/MaxStreet * Street;
 
 
  this->Canvas->MoveTo( 0, CurrStreet );
  for( unsigned x=0; x<this->Width + Shift; x++ )
    {
    double CosPer = cos( x / Street/(T/2) );
    unsigned SaveX = x - Shift,
             SaveY = CurrStreet - Amplitude * CosPer;
 
    this->Canvas->LineTo( SaveX, CurrStreet - Amplitude * CosPer );
 
    for( unsigned floor=SaveY; floor<CurrStreet + Amplitude; ++floor )
      if( !(floor % 3) &&    // Пролет меж этажами
            random (3)     ) // Есть дома кто
        this->Canvas->Pixels[SaveX][floor] = clWindowCity;
      else
        this->Canvas->Pixels[SaveX][floor] = clWalls;
 
    }// end current street
  }
}