problem in moving line using mouse C++

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Hi
my code allow user draw lines then he can do any modifications on it such as: change line properties ,delete line ,change its length and move it

I did code most of them but I could not do the moving part I wrote these lines for it but when I run the code the lines get disappear:

the part related to move shapes

C++

vector<Line*> mylines; // vector of all line objects

#include "stdafx.h"
#include "Lines.h"
#include <windows.h>
#include "patron1View.h"

// the class for creating line objects and draw it
Line::Line()
   {
color=RGB(0,0,0);
   }

void Line::setPoints(POINT s,POINT e){
	  start=s;
	  end=e;
	
	}//setpoints

POINT Line::getspoints(){
return start;
}

POINT Line::getepoints(){
return end;
}

void Line::setColor(int c){
	switch(c){
	case 1:
		color=RGB(255,0,0);//red
		break;
	case 2:
		color=RGB(0,0,255);//blue
		break;
	case 3:
		color=RGB(20,255,0);//green
		break;
	default: color=RGB(0,0,0);//black
		break;
	}//switch
}

void Line::setStyle(int c){
	                                    
	 style=c; 

}



void Line::drawline(CDC* pDC){
	
	pDC->SetMapMode(MM_LOMETRIC);
	if(style==1){
      mypen.CreatePen(PS_DOT,1,color);
	}else if(style==2){
      mypen.CreatePen(PS_DASH,1,color);
	}else if(style==3){
      mypen.CreatePen(PS_DASHDOT,1,color);
	}else {
	 mypen.CreatePen(PS_SOLID,1,color);
	}
	
      pDC->SelectObject(&mypen);
	  pDC->MoveTo ( start.x, start.y) ;
      pDC->LineTo (end.x,end.y ) ;
}




//the below code written within view.cpp class
/////////////////////////

CScrollView::OnLButtonDown(nFlags, point){


 CClientDC dc(this);
	  dc.SetMapMode(MM_LOMETRIC);
	  OnPrepareDC(&dc); // set up mapping mode and viewport origin
       dc.DPtoLP(&point);
     


if(sel){
relativest.x=mylines.at(selind)->getspoints().x-point.x;
relativest.y=mylines.at(selind)->getspoints().y-point.y;
relativend.x=mylines.at(selind)->getepoints().x-point.x;
relativend.y=mylines.at(selind)->getepoints().y-point.y;
   }


	CScrollView::OnLButtonDown(nFlags, point);
}


void Cpatron1View::OnMouseMove(UINT nFlags, CPoint point)
{
	CClientDC dc(this);
    dc.SetMapMode(MM_LOMETRIC);
     OnPrepareDC(&dc); // set up mapping mode and viewport origin
     dc.DPtoLP(&point);
	Cpatron1Doc* doc = GetDocument(); 

//do move shape
	if(((nFlags& MK_LBUTTON)== MK_LBUTTON)&&sel){
	relativest.x= point.x + relativest.x;
	relativest.y= point.x + relativest.y;
	relativend.x= point.x + relativend.x;
	relativend.y= point.x +relativend.y;
     }

CScrollView::OnMouseMove(nFlags, point);
}


void Cpatron1View::OnLButtonUp(UINT nFlags, CPoint point)
{

      
      CClientDC dc(this);
     dc.SetMapMode(MM_LOMETRIC);
     OnPrepareDC(&dc); // set up mapping mode and viewport origin
     dc.DPtoLP(&point);
          

if(sel){
	relativest.x= point.x + relativest.x;
	relativest.y= point.x + relativest.y;
	relativend.x= point.x + relativend.x;
	relativend.y= point.x +relativend.y;
	mylines.at(selind)->setPoints(relativest,relativend);
     }

CScrollView::OnLButtonUp(nFlags, point);
}

I think they disappear according to the map mode I use the below equation did no work correctly:

OnLButtonDown:

C++

relativest.x=mylines.at(selind)->getspoints().x-point.x;
relativest.y=mylines.at(selind)->getspoints().y-point.y;
relativend.x=mylines.at(selind)->getepoints().x-point.x;
relativend.y=mylines.at(selind)->getepoints().y-point.y;

on mouse move:

C++

relativest.x= point.x + relativest.x;
relativest.y= point.x + relativest.y;
relativend.x= point.x + relativend.x;
relativend.y= point.x +relativend.y;
mylines.at(selind)->setPoints(relativest,relativend);

could you please help me in doing this

thanks

Posted 12-Nov-12 8:17am

Member 9481941

Updated 12-Nov-12 8:25am

Nelek

v2

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Comments

chaau 12-Nov-12 16:47pm

1. Can you clarify what is relativest and relativend, and where they are defined.
2. I do not believe it is a good idea to call drawing functions inside Mouse events. I think yon need to call Invalidate() within these events and do all the drawing within OnPaint()
3. Can you show where you defined and initialised sel and selind variables

2 solutions

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This content, along with any associated source code and files, is licensed under The Code Project Open License (CPOL)

Member 9481941 · Answer 1 · 2012-11-13T00:39:00

relativest >> it save the start point for the line
relativend >> it save the end point for the line
all variables defined in the view class

I did the draw inside the on draw function
I only set the points on the mouse events:
here the ondraw function

C++

void Cpatron1View::OnDraw(CDC* pDC)
{
	pDC->SetMapMode ( MM_LOMETRIC) ;
	Cpatron1Doc* pDoc = GetDocument();
	ASSERT_VALID(pDoc);
	if (!pDoc)
		return;

**********************************************

//draw lines
for(int i=0;i<(int)mylines.size();i++){
mylines.at(i)->drawline(pDC);
}

}

here I set the sel value to true if the line selected by user

C++

void Cpatron1View::OnLButtonDown(UINT nFlags, CPoint point)
{   Cpatron1Doc* doc = GetDocument(); 
	
      CClientDC dc(this);
	  dc.SetMapMode(MM_LOMETRIC);
	  OnPrepareDC(&dc); // set up mapping mode and viewport origin
       dc.DPtoLP(&point);
     
for(int i=0;i<(int)mylines.size();i++){
		
		sel=HitTestLine(mylines.at(i)->getspoints(),      mylines.at(i)->getepoints(), point, 6);
		selind=i;
		if(sel== true){
		mylines.at(selind)->setColor(1);
		selcurve=false;
		Invalidate();
		break;
		}
	}
	
}//for


	
	CScrollView::OnLButtonDown(nFlags, point);
}

//here set the relativest and relativend value and dragged to true

C++

void Cpatron1View::OnLButtonDblClk(UINT nFlags, CPoint point)
{
	CClientDC dc(this);
     dc.SetMapMode(MM_LOMETRIC);
     OnPrepareDC(&dc); // set up mapping mode and viewport origin
     dc.DPtoLP(&point);
	
         
//prepare to move the shapes
	if(sel){
		relativest.x=mylines.at(selind)->getspoints().x-point.x;
		relativest.y=mylines.at(selind)->getspoints().y-point.y;
		relativend.x=mylines.at(selind)->getepoints().x-point.x;
		relativend.y=mylines.at(selind)->getepoints().y-point.y;
		dragged=true;
   }
   

	 
	CScrollView::OnLButtonDblClk(nFlags, point);
}

// here set the new points for the shape as the mouse moved

C++

void Cpatron1View::OnMouseMove(UINT nFlags, CPoint point)
{
	CClientDC dc(this);
    dc.SetMapMode(MM_LOMETRIC);
     OnPrepareDC(&dc); // set up mapping mode and viewport origin
     dc.DPtoLP(&point);
	
	   
	

	
	//do move shape
	if(((nFlags& MK_LBUTTON)== MK_LBUTTON) && dragged){
	
	relativest.x += point.x ;
	relativest.y += point.y ;
	relativend.x += point.x ;
	relativend.y += point.y;
	mylines.at(selind)->setPoints(relativest,relativend);
	Invalidate();
}

	
	CScrollView::OnMouseMove(nFlags, point);
}

here change the dragged to false to stop moving the shape

C++

void Cpatron1View::OnLButtonUp(UINT nFlags, CPoint point)
{
      
      CClientDC dc(this);
     dc.SetMapMode(MM_LOMETRIC);
     OnPrepareDC(&dc); // set up mapping mode and viewport origin
     dc.DPtoLP(&point);
          
      
	
	
	if(dragged){
		 
		dragged=false;
     }

	CScrollView::OnLButtonUp(nFlags, point);
}

please help me in find what wrong with moving part

Member 9481941 · Answer 2 · 2012-11-15T20:58:00

Solution 2

please help me I do not know how to update the value of the dragged line to get it running correctly

Posted 15-Nov-12 20:58pm

Member 9481941

problem in moving line using mouse C++

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problem in moving line using mouse C++

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