/*Graphics algorithm to impliment the BOUNDARY-FILL-4 Algorithm */

#include<dos.h>
#include<stdio.h>
#include<conio.h>
#include<graphics.h>
void drawpolygon(int n,int arr[][2],int color);
void boundfill4(int x,int y,int fill,int boundary);
void main()
{
    int arr[10][2],n,x,y;
    printf("Enter the number of edges : ");
    scanf("%d",&n);
    for(int i=0;i<n;i++)
    {
        printf("Enter the X and Y position for %d edge : ",i+1);
        scanf("%d %d",&arr[i][0],&arr[i][1]);
    }
    printf("Enter X and Y co-ordinates of the point from where you want n");
    printf("to start BOUNDARY-FILL : ");
    scanf("%d %d",&x,&y);
    int gd=DETECT,gm;
    initgraph(&gd,&gm,"c:\tc\bgi");
    drawpolygon(n,arr,RED);
    getch();
    boundfill4(x,y,BLUE,RED);
    getch();
    closegraph();
    restorecrtmode();
}
void drawpolygon(int n,int arr[][2],int color)
{
    setcolor(color);
    for(int i=0;i<n;i++)
    {
        if( i == n-1 )
            line(arr[i][0],arr[i][1],arr[0][0],arr[0][1]);
        else
            line(arr[i][0],arr[i][1],arr[i+1][0],arr[i+1][1]);
    }
}
void boundfill4(int x,int y,int fill,int boundary) //boundary=RED
{ //fill=BLUE
    int current;
    current = getpixel(x,y);
    if( (current != boundary) && (current != fill) )
    {
        delay(2);
        putpixel(x,y,fill);
        boundfill4(x+1,y,fill,boundary);
        boundfill4(x-1,y,fill,boundary);
        boundfill4(x,y+1,fill,boundary);
        boundfill4(x,y-1,fill,boundary);
    }
}




/*Graphics algorithm to impliment the BOUNDARY-FILL-8 Algorithm */

#include<dos.h>
#include<stdio.h>
#include<conio.h>
#include<graphics.h>
void boundfill8(int x,int y,int fill,int boundary);
void main()
{
    int r,x1,y1,x2,y2;
    printf("Enter Left and Top co-ordinates to draw a SQUARE : ");
    scanf("%d %d",&x1,&y1);
    printf("Enter Right and Bottom co-ordinates to draw a SQUARE : ");
    scanf("%d %d",&x2,&y2);

    int gd=DETECT,gm;
    initgraph(&gd,&gm,"c:\tc\bgi");
    setcolor(RED);
    rectangle(x1,y1,x2,y2);
    getch();
    printf("Enter X and Y co-ordinates to Fill a circle using BOUNDRY-FILL : ");
    scanf("%d %d",&x1,&y1);
    boundfill8(x1,y1,BLUE,RED);
    getch();
    closegraph();
    restorecrtmode();
}
void boundfill8(int x,int y,int fill,int boundary)
{
    int current;
    current = getpixel(x,y);
    if( (current != boundary) && (current != fill) )
    {

        putpixel(x,y,fill);
        delay(2);
        boundfill8(x-1,y-1,fill,boundary);
        boundfill8(x,y-1,fill,boundary);
        boundfill8(x+1,y-1,fill,boundary);
        boundfill8(x-1,y,fill,boundary);
        boundfill8(x+1,y,fill,boundary);
        boundfill8(x-1,y+1,fill,boundary);
        boundfill8(x,y+1,fill,boundary);
        boundfill8(x+1,y+1,fill,boundary);

    }
}