ALGORITMA BRASENHEM DENGAN OPENGL

#include<GL/glut.h>

#include<stdlib.h>

#include<math.h>

void setPixel(int px, int py)

{

    glBegin(GL_POINTS);

    glVertex2i(px, py);

    glEnd();

}

void algoritmaDDA( int x1, int y1, int x2, int y2)

{

     int dy = y2 - y1;

     int dx = x2 - x1;

     float t = (float) 0.5;

     setPixel(x1,y1);

     if (abs(dx) > abs(dy))

     {

                 float m = (float) dy / (float) dx;

                 t += y1;

                 dx = (dx<0) ? -1 : 1;

                 m *=dx;

                 while (x1 != x2)

                 {

                       x1 += dx;

                       t += m;

                       setPixel(x1, (int) t);

                 }

     }

     else {

          float m = (float) dx / (float) dy;

          t += x1;

          dy = (dy<0) ? -1 : 1;

          m += dy;

          while (y1 != y2)

          {

                y1 += dy;

                t +=m;

                setPixel((int)t,y1);

          }

     }

}

void lineMidpoint(int x0, int y0, int xEnd, int yEnd)

{

 int dx = xEnd - x0;

 int dy = y0 - yEnd;

 int p = 2 * dy + dx;

 int twoDy= 2 * dy;

 int twoDyminusDx = 2 * (dy + dx);

 int x, y;

 x= x0;

 y= y0;

 setPixel(x,y);

 while ( x<xEnd)

 {

 x++;

 if (p<0)

 {

 y++;

 p +=twoDyminusDx;

 }

 else {

 p += twoDy;

 }

 setPixel(x,y);

 }

}

void bresenham(int x1, int y1, int x2, int y2)

{

 int dy = y2 - y1;

 int dx = x2 - x1;

 int stepx, stepy;

 if(dy < 0)

 {

 dy = -dy; stepy = -1;

 }

 else

 {

 stepy = 1;

 }

 if(dx < 0) {

 dx = -dx;

 stepx = -1;

 }

 else

 {

 stepx = 1;

 }

 dy <<= 1;

 dx <<= 1;

 setPixel(x1,y1);

 if (dx > dy)

 {

 int fraction = dy - (dx >> 1);

 while (x1 != x2)

 {

 if(fraction >= 0)

 {

 y1 += stepy;

 fraction -= dx;

 }

 x1 += stepx;

 fraction += dy;

 setPixel(x1,y1);

 }

 }

 else

 {

 int fraction = dx - (dy >> 1);

 while (y1 != y2)

 {

 if(fraction >= 0)

 {

 x1 += stepx;

 fraction -= dy;

 }

 y1 += stepy;

 fraction += dx;

 setPixel(x1,y1);

 }

 }

}

void display()

{

    glClear(GL_COLOR_BUFFER_BIT);

    glColor3f(1.0,0.0,0.0);

    glPointSize(4.0);

    setPixel(100, 10);

    setPixel(220, 180);

    lineMidpoint(0,0,500,200);

    glFlush();

}

void init(void)

{

glClearColor(1.0,1.0,1.0,0.0);

glMatrixMode(GL_PROJECTION);

gluOrtho2D(0.0,500.0,0.0,500.0);

}

main(int argc, char**argv)

{

glutInit(&argc,argv);

glutInitDisplayMode(GLUT_SINGLE | GLUT_RGB);

glutInitWindowSize(500,500);

glutInitWindowPosition(0,0);

glutCreateWindow("ICHA KHAIRUNNISA");

init();

glutDisplayFunc(display);

glutMainLoop();

}