using System;

using System.Collections.Generic;

using System.Text;

using CsGL.Basecode;

using System.Drawing;

namespace BaiLab2

{

class VeDuongThang:Model

{

public Point A=new Point(0,0);

public Point B=new Point(500,500);

public override void Initialize()

{

base.Initialize();

}

public override void Draw()

{

base.Draw();

glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);

glColor3f(1.0f, 1.0f, 0.0f);

// Line_DDA(A, B);

glPointSize(3);

// glRotatef(100, 1, 1, 1);

glBegin(GL_POINTS);

// Ve2DuongThangCatNhau(200);

Line_Bresenham(A, B);

Bresenham1(A, new Point(-100,-80));

glEnd();

}

public void Ve2DuongThangCatNhau(int a)

{

for (int i = -a; i < a;i++)

{

glVertex2i(i, 0);

glVertex2i(0, i);

}

}

//Ve duong thang voi DDA

public void Line_DDA(Point A, Point B)

{

int dx = B.X - A.X;

int dy = B.Y - A.Y;

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

int x;

float y = (float)A.Y;

for (x = A.X; x < B.X;x++ )

{

glBegin(GL_POINTS);

glVertex2i(x, (int)y);

y += k;

glEnd();

}

}

//Ve Duong Thang voi Bresenham truong hop 0<m<1

public void Line_Bresenham(Point A, Point B)

{

int dx = B.X - A.X, dy = B.Y - A.Y, P = 2*dy - dx;

int x;

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

int y =(int)A.Y;

List<Point> kq = new List<Point>();

for(x=A.X;x<B.X;x++)

{

kq.Add(new Point(x,y));

if (k > 0 && k <= 1)

{

if (P < 0)

{

P = P + 2 * dy;

}

else

{

y++;

P = P + 2 * dy - 2 * dx;

}

}

}

for(int i=0;i<kq.Count;i++)

{

glVertex2i(kq[i].X, kq[i].Y);

}

}

//Ham Hoan Vi

public void HoanVi(ref Point A, ref Point B)

{

Point temp = A;

A = B;

B = temp;

}

//Truong hop m<0

public void Bresenham1(Point A, Point B)

{

int dx = B.X - A.X, dy = B.Y - A.Y, P = 2*dy - dx;

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

bool f1=false,f2=false;

int x;

int y = A.X;

Point temp;

if (A.X == B.X)

{

if (A.Y > B.Y)

HoanVi(ref A, ref B);

for (int i = A.Y; i < B.Y; i++)

glVertex2i(A.X, i);

}

if (A.Y == B.Y)

{

if (A.X > B.X)

HoanVi(ref A, ref B);

for (int i = A.X; i < B.X; i++)

glVertex2i(i, A.Y);

}

if (A.X > B.X)

HoanVi(ref A, ref B);

if (A.Y>B.Y)

{

f1 = true;

Point tam = A;

A = B;

B=new Point(2*B.X-tam.X,tam.Y);

}

if (dy>dx)

{

f2 = true;

int tam = A.X;

A.X = A.Y;

A.Y = tam;

tam = B.X;

B.X = B.Y;

B.Y = tam;

}

dx = B.X - A.X;

dy = B.Y - A.Y;

P = 2*dy - dx;

List<Point> kq = new List<Point>();

for (x = A.X; x < B.X; x++)

{

kq.Add(new Point(x, y));

if (P < 0)

{

P = P + 2 * dy;

}

else

{

y++;

P = P + 2 * dy - 2 * dx;

}

}

if(f1==true)

{

for(int i=0;i<kq.Count;i++)

{

temp=kq[i];

kq[i]=new Point(2*A.X-temp.X,temp.Y);

}

}

if (f2 == true)

{

for (int i = 0; i < kq.Count; i++)

{

temp = kq[i];

kq[i] = new Point(temp.Y,temp.X);

}

}

for(int i=0;i<kq.Count;i++)

{

glVertex2i(kq[i].X, kq[i].Y);

}

}

//Ve Duong Thang voi MidPoint

}

}