C / C++ / MFC

18-Dec-06 17:54

See Path Field Limits
[^] I think Its better you use of constants

WhiteSky

program cannot execute..

cyn818-Dec-06 16:03

cyn8

18-Dec-06 16:03

Hi, i wrote some codes so that in a MFC dialog based application, i'm able to display a triangle(drawn using CPen and MoveTo and LineTo) in the custom control when i click a button. May i know how to do it correctly? The codes that i wrote cannot execute although it was able to complile n link without error,
thanks

Hamid_RT18-Dec-06 18:01

18-Dec-06 18:01

What errors?

WhiteSky

cyn818-Dec-06 18:04

cyn8

18-Dec-06 18:04

i'm using VC++6. the code generate no error while compiling but when i try to execute it, it does nothing. What may cause this to happen?

Hamid_RT18-Dec-06 18:13

18-Dec-06 18:13

Can you show your code that you writted for triangle and it doesnt work?

WhiteSky

cyn818-Dec-06 18:36

cyn8

18-Dec-06 18:36

Here is the code..but this is oni will draw lines.
////////this is testctrl.cpp//////////////////
void testctrl::OnPaint()
{

CPaintDC dc(this); // device context for painting

}

//////////////////////////////////
// Do not call CPropertyPage::OnPaint() for painting messages

void testctrl::Draw(CDC *pDC)
{
CRect rect;
CPen penBlack;
penBlack.CreatePen(PS_SOLID, 0, RGB(0,255,0));
CPen* pOldPen=pDC->SelectObject(&penBlack);
GetClientRect(rect);
int vectorValues[] = {1,1,0,0,1,1}; // for testing
int m_currentXCoord=0;

int width=10;
for(int i = 0; i < 19; i++)
{
if(vectorValues[i] == 1)
{
pDC->MoveTo(m_currentXCoord,10);
pDC->LineTo(m_currentXCoord+width,10);
m_currentXCoord = m_currentXCoord + width;
}

else

{
pDC->MoveTo(m_currentXCoord,20);
pDC->LineTo(m_currentXCoord+width,20);
m_currentXCoord = m_currentXCoord + width;

} // a 0 so only update X coordinate
}

pDC->SelectObject(pOldPen);
}

BOOL testctrl::OnEraseBkgnd(CDC* pDC)
{
// To avoid flickering
return CWnd::OnEraseBkgnd(pDC);
// return TRUE;
}
/////////////////////////////////////////////////

/////////////this is testdlg.cpp/////////////////////
void CTestDlg::OnButton1()
{
// TODO: Add your control notification handler code here
CDC dc;
m_custom.Draw(&dc);
UpdateData(FALSE);
UpdateDialogControls(this,FALSE);
}

void CTestDlg::OnUpdateStart(CCmdUI* pCmdUI)
{
pCmdUI->Enable(TRUE);
}
/////////////////////////////////////////////////
thanks for ur help

Hamid_RT18-Dec-06 18:44

Re: program cannot execute.. [modified]

18-Dec-06 18:44

CDC dc;
m_custom.Draw(&dc);
what happens if you use of this code instead above code

<br />
CDC *dc;<br />
dc=GetDC();<br />
m_custom.Draw(dc);<br />

WhiteSky

prasad_som18-Dec-06 20:08

prasad_som

18-Dec-06 20:08

cyn8 wrote:
/////////////this is testdlg.cpp/////////////////////
void CTestDlg::OnButton1()
{
// TODO: Add your control notification handler code here
CDC dc;
m_custom.Draw(&dc);
UpdateData(FALSE);
UpdateDialogControls(this,FALSE);
}

You are passing uninitialized CDC object to Draw. What you are doing ? It should call this way in first place. You need to use UpdateWindow like function in combination with Invalidate.

-- modified at 2:21 Tuesday 19th December, 2006

-- modified at 5:04 Tuesday 19th December, 2006

Prasad
Notifier using ATL | Operator new[],delete[][^]

Hamid_RT18-Dec-06 20:31

18-Dec-06 20:31

I think he forgots to set dc Smile | :)

WhiteSky

Hamid_RT19-Dec-06 7:25

19-Dec-06 7:25

Does your problem solve?

WhiteSky

to reduce footprint

George_George18-Dec-06 15:51

18-Dec-06 15:51

Hello everyone,

I am wondering how to reduce the footprint of a binary build (C/C++) program generated by gcc.

1. Any ideas of reduce the footprint of a debug version build?
2. Any ideas of reduce the footprint of a release version build?

I think some linker or compiler options may help, what are they? Any other ideas to reduce footprint?

thanks in advance,
George

Paul Conrad25-Dec-06 19:01

Paul Conrad

25-Dec-06 19:01

George_George wrote:
I am wondering how to reduce the footprint of a binary build (C/C++) program generated by gcc

Don't use gcc. Even if you optimize for size, it will still be pretty bloated compared to other C++ compilers...

If you try to write that in English, I might be able to understand more than a fraction of it. - Guffa

George_George27-Dec-06 6:09

Re: to reduce footprint [modified]

27-Dec-06 6:09

Thanks PaulC1972!

Do you have more detailed comments or advices (for example, why gcc will generate larger code)? Or some reference documents to read?

regards,
George

Paul Conrad27-Dec-06 6:18

Paul Conrad

27-Dec-06 6:18

George_George wrote:
why gcc will generate larger code?

Not 100% sure. Look at Comparing C++ Compilers, October 2003 Dr. Dobb's Journal[^], and at C/C++ Compiler Optimization, May 2004 Dr. Dobb's Journal[^]. The May issue was a good one about optimization and tuning performance. Both issues are worth looking at.

Last modified: 1hr 48mins after originally posted -- Clickities added to referenced articles...

Some people have a memory and an attention span, you should try them out one day. - Jeremy Falcon

George_George30-Dec-06 7:18

30-Dec-06 7:18

Very good reference, thanks PaulC1972!

regards,
George

Paul Conrad30-Dec-06 7:27

Paul Conrad

30-Dec-06 7:27

No problem, George. After this thread started, I ended up rereading those articles I referred you to Big Grin | :-D

George_George4-Jan-07 18:42

Validate and Invalidate in RedrawWindow() [modified]

4-Jan-07 18:42

Wow... Could you briefly describe the main idea of the articles in your words? Articles are long...

regards,
George

rp_suman18-Dec-06 15:22

18-Dec-06 15:22

For what purpose do we need VALIDATE and INVALIDATE flags in RedrawWindow()?
What is the difference between them?
Thanks & Regards,
Suman

-- modified at 23:02 Monday 18th December, 2006

Re: Validate and Invalidate in RedrawWindow() [modified]

Stephen Hewitt18-Dec-06 15:41

Stephen Hewitt

18-Dec-06 15:41

InvalidateRect and friends just marks a region of a window as "dirty" and it will be repainted at some time in the future. RedrawWindow causes a redraw to happen on the spot; even so, depending on the flags passed, only the "dirty" regions may be redrawn.

Steve

prasad_som18-Dec-06 17:59

prasad_som

18-Dec-06 17:59

rp_suman wrote:
For what purpose do we need VALIDATE and INVALIDATE

Invalidate flags adds specified windows rect , regn to window to be repainted.
Validate flags removes specified windows rect , regn from window to be repainted.(In short it removes dirty flag).

-- modified at 0:06 Tuesday 19th December, 2006

Prasad
Notifier using ATL | Operator new[],delete[][^]

rp_suman18-Dec-06 19:21

18-Dec-06 19:21

Thanks for great help from you both!!
Thanks & Regards,
Suman

rp_suman19-Dec-06 21:31

19-Dec-06 21:31

RDW_NOCHILDREN flag should be used with which one, RDW_INVALIDATE or RDW_VALIDATE.
Is it meaningful to use with RDW_INVALIDATE.
Thanks & Regards,
Suman

prasad_som27-Dec-06 18:08

prasad_som

27-Dec-06 18:08

rp_suman wrote:
Is it meaningful to use with RDW_INVALIDATE

Yes, ofcourse.

If you have new question, start new thread, users here usually doesn't turn back to to old posts( but I do in this case Smile | :)

) , unless got any email notification.

Prasad
Notifier using ATL | Operator new[],delete[][^]

rp_suman2-Jan-07 5:19