Растеризация с использованием исключающего ИЛИ

//---------------------------------------------------------------------------
 
#include <vcl.h>
#include <math.h>
#include <algorithm>
#pragma hdrstop
 
#include "Unit1.h"
//---------------------------------------------------------------------------
#pragma package(smart_init)
#pragma resource "*.dfm"
TForm1 *Form1;
TPoint x[100];
TPoint reb[100];
TPoint mypoint;
int i=0;
//---------------------------------------------------------------------------
__fastcall TForm1::TForm1(TComponent* Owner)
    : TForm(Owner)
{
}
//---------------------------------------------------------------------------
void __fastcall TForm1::FormMouseDown(TObject *Sender, TMouseButton Button,
      TShiftState Shift, int X, int Y)
{
x[i].x=X;
x[i].y=Y;
i++;
}
//---------------------------------------------------------------------------
void __fastcall TForm1::Button1Click(TObject *Sender)
{
int j=0;
for (j=0; j < i; j++)
  {
  Form1->Canvas->MoveTo(x[j%i].x,x[j%i].y);
  Form1->Canvas->LineTo(x[(j+1)%i].x,x[(j+1)%i].y);
  }
}
//---------------------------------------------------------------------------
int povorot(TPoint x,TPoint y)
{
  if ((((int)(x.x)*(int)(y.y))-((int)(y.x)*(int)(x.y)))<=0)
  {
    return -1;
  }
  else return 1;
}
//---------------------------------------------------------------------------
int min(int a, int b)
{
    return(a<b?a:b);
}
//---------------------------------------------------------------------------
int max(int a, int b)
{
    return(a>b?a:b);
}
 
//---------------------------------------------------------------------------
 
void __fastcall TForm1::Button3Click(TObject *Sender)
{
i=0;
Canvas->Rectangle(-1,-1,Width+1,Height+1);
}
//---------------------------------------------------------------------------
int IsInside(TPoint V[], int n, TPoint p)
{
  int count=0;
  for (int b = 0; b < n; b++)
  {
    int j=(b+1)%n;
    if (V[b].y==V[j].y) continue;
    if (V[b].y>p.y&&V[j].y>p.y) continue;
    if (V[b].y<p.y&&V[j].y<p.y) continue;
    if ((min(V[b].y,V[j].y)==p.y)&&(min(V[b].x,V[j].x)>=p.x)) count++;
    else
    if (max(V[b].y,V[j].y)==p.y) continue;
    else
    {
    double t=((double)(p.y-V[b].y)/(V[j].y-V[b].y));
    if (V[b].x+t*(V[j].x-V[b].x)>=p.x) count++;
    }
  }
  return count&1;
}
 
//---------------------------------------------------------------------------
 
void __fastcall TForm1::Button4Click(TObject *Sender)
{
TPoint mymax(0,0),mymin(Width,Height);
int j=0;
  for (j = 0; j < i; j++)
  {
    if (mymin.x>x[j%i].x) mymin.x=x[j%i].x;
    if (mymin.y>x[j%i].y) mymin.y=x[j%i].y;
    if (mymax.x<x[j%i].x) mymax.x=x[j%i].x;
    if (mymax.y<x[j%i].y) mymax.y=x[j%i].y;
  };
for (j = mymin.x; j < mymax.x; j++)
  {
  for (int k = mymin.y; k < mymax.y; k++)
    {
     if (IsInside(x,i,TPoint(j,k)))
     {
       Form1->Canvas->Pixels[j][k]=clBlack;
     }
    }
  }
}