5. Write a program to create and fill the two dimensional object by using boundary fill algorithm

#include <GL/glut.h>
#include<math.h>
#include<stdio.h>
int ww = 600, wh = 500;
float fillCol[3] = {0.4,0.0,0.0};
float borderCol[3] = {0.0,0.0,0.0};
void setPixel(int, int, float[]);
void getPixel(int, int, float[]);
void resize(int, int);
void drawPolygon(int, int, int, int);
void boundaryFill4(int,int,float[],float[]);
void display();
void mouse(int, int, int, int);
int main(int argc, char** argv)
{
glutInit(&argc,argv);
glutInitDisplayMode (GLUT_SINGLE | GLUT_RGB);
glutInitWindowSize(ww,wh);
glutInitWindowPosition(500, 50);
glutCreateWindow("Bountry-Fill-Recursive");
glutDisplayFunc(display);
glutMouseFunc(mouse);
//calls whenever frame buffer window is resized
glutReshapeFunc(resize);
glutMainLoop();
return 0;
}
void setPixel(int pointx, int pointy, float f[3])
{
glBegin(GL_POINTS);
glColor3fv(f);
glVertex2i(pointx,pointy);
glEnd();
glFlush();
}
void getPixel(int x, int y, float pixels[3])
{
glReadPixels(x,y,1.0,1.0,GL_RGB,GL_FLOAT,pixels);
}
void resize(int w, int h)
{
glMatrixMode(GL_PROJECTION); //set projection paramaters
glLoadIdentity();
gluOrtho2D(0.0,w,0.0,h);
glutReshapeWindow(ww, wh);
glViewport(0.0, 0.0, w, h);
}
void drawPolygon(int x1, int y1, int x2, int y2)
{
glColor3f(0.0, 0.0, 0.0);
glBegin(GL_LINE_LOOP);
glVertex2i(x1, y1);
glVertex2i(x1, y2);
glVertex2i(x2,y2);
glVertex2i(x2,y1);
glEnd();
glFlush();
}
void display()
{
glClearColor(1.0, 1.0, 1.0, 1.0);
glClear(GL_COLOR_BUFFER_BIT);
//If you modify following values, u should change condition in mouse() also.
drawPolygon(150,250,200,300);
glFlush();
}
void boundaryFill4(int x,int y,float fillColor[3],float borderColor[3])
{
float interiorColor[3];
getPixel(x,y,interiorColor);
if(((interiorColor[0]!=borderColor[0] && (interiorColor[1])!=borderColor[1]
&& (interiorColor[2])!=borderColor[2]) && (interiorColor[0]!=fillColor[0]
&& (interiorColor[1])!=fillColor[1] && (interiorColor[2])!=fillColor[2])))
{
setPixel(x,y,fillColor);
boundaryFill4(x+1,y,fillColor,borderColor);
boundaryFill4(x-1,y,fillColor,borderColor);
boundaryFill4(x,y+1,fillColor,borderColor);
boundaryFill4(x,y-1,fillColor,borderColor);
}
}
void mouse(int btn, int state, int x, int y)
{
//This check is based on size of the polygon mentioned in display() function
if(((x<150 || x>200) ||( y<200 || y>250)))
printf("Invalid click !!\n");
else
if(btn==GLUT_LEFT_BUTTON && state == GLUT_DOWN)
{
int xi = x;
int yi = (wh-y);
boundaryFill4(xi,yi,fillCol,borderCol);
}
}