Check two rectangles are intersecting or not in c# windows application

how to check two rectangles are intersecting or not....

I have list with how many rectangles I have drawn over panel. when I am drawing a new rectangle I need to check whether this rectangle is intersecting or not. If intersecting means that intersected area need to fill with user choose color. I tried so many ways I could not found any suitable answer for my application.i have present drawing rectangle details but I need to check with other rectangle details whether intersecting or not means I am not getting how to do. So please anyone help me this is highly preferable.

below i am sharing code

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.IO;
using System.Linq;
using System.Reflection;
using System.Text;
using System.Text.RegularExpressions;
using System.Threading.Tasks;
using System.Windows.Forms;
namespace DisplayRectangleBox
{
public partial class Form1 : Form
{
List Rectangles = new List();
//List pens = new List();
Dictionary rectangle = new Dictionary();
Pen pen1;
int x, y, w, h,x1,y1,w1,h1;
int r1, r2;
int height, width;
bool isvalid = false;
const int padding = 1;
public string color;
public string intersectcolor;
Color c ;
Graphics g;
int Dimension;
// Brush brush;
public Form1()
{
InitializeComponent();
}
//class Point
//{
// public int a,b;
//}
//static bool overlap(Point l1,Point r1, Point l2, Point r2)
//{
// if (l1.a >= r2.a || l2.a >= r2.a)
// {
// return false;
// }
// if (l1.b >= r2.b || l2.b >= r2.b)
// {
// return false;
// }
// return true;
//}
//public void Intersectclip(System.Drawing.Rectangle rct);
//private void IntersectclipRectangle(PaintEventArgs e)
//{
// //Rectangle cliprectangle = new Rectangle(x, y, w, h);
// //e.Graphics.SetClip(cliprectangle);
// Rectangle intersectrect = new Rectangle(x1, y1, w1, h1);
// e.Graphics.IntersectClip(intersectrect);
// //e.Graphics.DrawRectangle(iteam.Key, iteam.Value);
//}
private void panel1_Paint(object sender, PaintEventArgs e)
{
if (isvalid)
{
Color c = Color.FromName(color);
Pen pen1 = new Pen(c,2);
Rectangle rect = new Rectangle(x, y, w, h);
rectangle.Add(pen1,rect);
foreach (KeyValuePair iteam in rectangle)
{
Graphics g = e.Graphics;
g.DrawRectangle(iteam.Key,iteam.Value);
}
//var rectdetails = from angle in rectangle
//where angle.Key= rect
//select new Rectangle(x1,y1,w1,h1);
//if(CheckIfAnyInteresect())
//{
//}
//Color clr = Color.FromName(intersectcolor);
//Brush brush = new SolidBrush(clr);
//Rectangle rect1 = new Rectangle(x, y, w, h);
//e.Graphics.SetClip(rect1);
//Rectangles.Add(rect1);
//Rectangle intersectrect = new Rectangle(x1, y1, w1, h1);
//e.Graphics.IntersectClip(intersectrect);
//e.Graphics.FillRectangle(brush, intersectrect);
//foreach(KeyValuePair val in rectangle)
//{
// int n=rectangle.Count;
//}
//int left = max(r1.left, r2.left);
//int right = min(r1.right, r2.right)
//int bottom = max(r1.bottom, r2.bottom)
//int top = min(r1.top, r2.top)
//Point l1 = new Point(), r1 = new Point(),
//l2 = new Point(), r2 = new Point();
// l1.a = x; l1.b = y; r1.a = y; r1.b = x;
// l2.a = x; l2.b = y; r2.a = y; r2.b = x;
// if (overlap(l1, r1, l2, r2))
// {
// MessageBox.Show("Rectangle overlaps");
// }
// else
// {
// MessageBox.Show("Rectangle not overlaps");
// }
}
}
//static void FindPoints(int x1, int y1,
// int x2, int y2,
// int x3, int y3,
// int x4, int y4)
//{
// int x5 = Math.Max(x1, x3);
// int y5 = Math.Max(y1, y3);
//}
bool CheckIfAnyInteresect(IEnumerable rectangles)
{
return rectangles.Any(rect => rectangles.Where(r => !r.Equals(rect)).Any(r => r.IntersectsWith(rect)));
}
//static internal Rectangle intersect(Rectangle lhs, Rectangle rhs)
//{
// //int lhsLeft = lhs.Location.X;
// //int rhsLeft = rhs.Location.X;
// //int lhsTop = lhs.Location.Y;
// //int rhsTop = rhs.Location.Y;
// //int lhsRight = lhs.Right;
// //int rhsRight = rhs.Right;
// //int lhsBottom = lhs.Bottom;
// //int rhsBottom = rhs.Bottom;
// //Dimension left = Dimension.max(lhsLeft, rhsLeft);
// //Dimension top = Dimension.max(lhsTop, rhsTop);
// //Dimension right = Dimension.min(lhsRight, rhsRight);
// //Dimension bottom = Dimension.min(lhsBottom, rhsBottom);
// //Point location = new Point(left, top);
// //Dimension width = (right > left) ? (right - left) : new Dimension(0);
// //Dimension height = (bottom > top) ? (bottom - top) : new Dimension(0);
// return new Rectangle(location, new Size(width, height));
//}
private bool Validate()
{
if (string.IsNullOrEmpty(txtX.Text) || string.IsNullOrEmpty(txtY.Text) || string.IsNullOrEmpty(txtWidth.Text) || string.IsNullOrEmpty(txtHeight.Text))
{
MessageBox.Show("Please fill all the feilds ");
}
else
{
x = Convert.ToInt32(txtX.Text);
y = Convert.ToInt32(txtY.Text);
w = Convert.ToInt32(txtWidth.Text);
h = Convert.ToInt32(txtHeight.Text);
height = panel1.Height - y - padding;
width = panel1.Width - x - padding;
if (w > width || h > height)
{
h = Math.Min(h, height);
w = Math.Min(w, width);
string message = ("The given size and location are not fit to this area, so we are adjusting rectangle withine drawing area.If you want to draw press 'OK'");
string title = ("Please Confirm Your Action");
MessageBoxButtons buttons = MessageBoxButtons.OKCancel;
DialogResult result = MessageBox.Show(message, title, buttons);
if (result == DialogResult.OK)
{
Graphics g = panel1.CreateGraphics();
g.DrawRectangle(Pens.Black, x, y, w, h);
txtHeight.Text = Convert.ToString(height);
txtWidth.Text = Convert.ToString(width);
panel1.Invalidate();
}
else if (result == DialogResult.Cancel)
{
isvalid = false;
return isvalid;
}
}
}
isvalid = true;
return isvalid;
}
private void panel2_SizeChanged(object sender, EventArgs e)
{
var w = Math.Max(panel1.Width, panel2.Width);
var h = Math.Max(panel1.Height, panel2.Height);
panel1.MinimumSize = new Size(w, h);
}
private void ClearForm()
{
rectangle.Clear();
cmbBoarderclr.Items.Clear();
cmbIntersectcolor.Items.Clear();
txtX.Text = "";
txtY.Text = "";
txtWidth.Text = "";
txtHeight.Text = "";
cmbBoarderclr.Text = "";
isvalid = false;
panel1.Invalidate();
txtX.Focus();
}
private void btnAdd_Click(object sender, EventArgs e)
{
if (Validate())
{
panel1.Invalidate();
}
}
private void btnReset_Click_1(object sender, EventArgs e)
{
ClearForm();
}
private void txtX_KeyPress(object sender, KeyPressEventArgs e)
{
if (!(Char.IsDigit(e.KeyChar) || (e.KeyChar == (char)Keys.Back)))
e.Handled = true;
}
private void txtY_KeyPress(object sender, KeyPressEventArgs e)
{
if (!(Char.IsDigit(e.KeyChar) || (e.KeyChar == (char)Keys.Back)))
e.Handled = true;
}
private void txtHeight_KeyPress(object sender, KeyPressEventArgs e)
{
if (!(Char.IsDigit(e.KeyChar) || (e.KeyChar == (char)Keys.Back)))
e.Handled = true;
}
private void txtWidth_KeyPress(object sender, KeyPressEventArgs e)
{
if (!(Char.IsDigit(e.KeyChar) || (e.KeyChar == (char)Keys.Back)))
e.Handled = true;
}
private void cmbBoarderclr_SelectedIndexChanged(object sender, EventArgs e)
{
color = this.cmbBoarderclr.SelectedItem.ToString();
}
private void cmbBoarderclr_DrawItem(object sender, DrawItemEventArgs e)
{
//Graphics g = e.Graphics;
//Rectangle rect = e.Bounds;
//if (e.Index >= 0)
//{
// string n = ((ComboBox)sender).Items[e.Index].ToString();
// Font f = new Font("Arial", 9, FontStyle.Regular);
// Color c = Color.FromName(n);
// Brush b = new SolidBrush(c);
// g.DrawString(n, f, Brushes.Black,rect);
// g.FillRectangle(b, rect);
//}
}
private void cmbBoarderclr_Click(object sender, EventArgs e)
{
Type colorType = typeof(System.Drawing.Color);
PropertyInfo[] propInfoList = colorType.GetProperties(BindingFlags.Static | BindingFlags.DeclaredOnly | BindingFlags.Public);
foreach (PropertyInfo c in propInfoList)
{
this.cmbBoarderclr.Items.Add(c.Name);
}
}
private void Form1_Load(object sender, EventArgs e)
{
}
private void cmbIntersectcolor_Click(object sender, EventArgs e)
{
Type colorType = typeof(System.Drawing.Color);
PropertyInfo[] propInfoList = colorType.GetProperties(BindingFlags.Static | BindingFlags.DeclaredOnly | BindingFlags.Public);
foreach (PropertyInfo c in propInfoList)
{
this.cmbIntersectcolor.Items.Add(c.Name);
}
}
private void cmbIntersectcolor_SelectedIndexChanged(object sender, EventArgs e)
{
intersectcolor = this.cmbIntersectcolor.SelectedItem.ToString();
}
}
}

1 Reply

Know the answer? Post it — somebody with the same question will find it here.

Željko Perić5y ago
Hello https://www.c-sharpcorner.com/members/shilpa-jajee

Here is a link to an article that could solve the problem:

https://helloacm.com/rectangle-intersection-test/

All the best,
Željko Peric
0