C / C++ / MFC Discussion Boards

three views + three opengl windows + crashes when fullscreen

bbbilen26-Dec-02 9:54

26-Dec-02 9:54

hi all,

I have MDI app. whish has 1 document 3 view objects. I'll display three different graphical scenes in each window. So I modified view classes (CView1, CView2, CView3) in order to use opengl... I setup pixel formet get rendering context, make current etc...
if I modify only one view class app. works (only one view displays graphical scene), BUT if I modify 2 or all view classes for opengl, app. locks when I make full screen. If I comment wglMakeCurrent line app. doesnt lock. What's the problem with wglMakeCurrent..
if((::wglMakeCurrent(m_pDC->GetSafeHdc(), m_hRC))==false)
{
MessageBox("Cant make rend. context current");
return false;
}
If wglMakeCurrent runs in one view everthing is OK, But if all views run wglmakecurrent it crashes when I make fullscreen? I guess that all of the rendering contexts cant be made current at the same time, but why doesnt it crash when working in non-fullscreen mode..
I want to know what wglMakeCurrent exactly does? And why it crashes when I make fullscreen?

a second question:
Is there a tool that I can draw geometrical objects (2d or 3d) and tool creates opengl code for the objects?

sorry It was a long post but my english is this enough

Re: three views + three opengl windows + crashes when fullscreen

KaЯl26-Dec-02 23:49

KaЯl

26-Dec-02 23:49

You should probably refer to the excellent article CGLEnabledView - An MDI view class supporting OpenGL
[^],you will find useful info into.
wglMakeCurrent associates/de-associates the OpenGL rendering context to the Win32 device context.
Sometimes with OpenGL the problem comes not from the code, but from the implementation of OpenGL in the video card, that's why I would advise to test the application on different computers using different video cards.
I've no idea about your second question, but if you find such a tool, I would be happy to know it, TIA ! Smile | :)

HTH,

K.

One small village of indomitable geeks still holds out against the invaders. And life is not easy for the managers legionaries who garrison the fortified camps of Microsoftum, Javum, Ceplumplum and Vebasum

Re: three views + three opengl windows + crashes when fullscreen

bbbilen29-Dec-02 8:36

bbbilen

29-Dec-02 8:36

thanks for the link..
and I found a program named Deep Exploration that can convert 3d studio or other files to opengl source
www.righthemisphere.com

c++ and managed c++

joshfl26-Dec-02 8:30

joshfl

26-Dec-02 8:30

hey everyone... whats the difference between managed c++ and regular c++??

Re: c++ and managed c++

AlexO26-Dec-02 8:37

AlexO

26-Dec-02 8:37

Regular c++ is not managed Smile | :)

. The difference is that managed is executed under .Net runtime (or whatever they call it) therefore there are certain limitation/differences. Totally different memory allocation, memory access(mostly none), data types etc.

Re: c++ and managed c++

S O S26-Dec-02 9:47

S O S

26-Dec-02 9:47

Is there an article or website that describes the details and differences of both?

Re: c++ and managed c++

Vagif Abilov26-Dec-02 9:45

Vagif Abilov

26-Dec-02 9:45

Managed C++ is .NET dialect of C++. As you probably know, in .NET it is Common Language Runtime that manages lifetime of objects, while in "raw" C++ it is entirely up to you how to manage memory. If you compile a C++ application with /CLR compile switch, you can make CLR calls from inside your C++ program.

Вагиф Абилов
MCP (Visual C++)
Oslo, Norway

Hex is for sissies. Real men use binary. And the most hardcore types use only zeros - uppercase zeros and lowercase zeros.
Tomasz Sowinski

Re: c++ and managed c++

Nish Nishant26-Dec-02 10:24

Nish Nishant

26-Dec-02 10:24

A simple intro to MC++ might help :-

http://www.codeproject.com/managedcpp/mcppintro01.asp

Nish

Author of the romantic comedy

Summer Love and Some more Cricket [New Win]

Review by Shog⁹
Click here for review[NW]

Re: c++ and managed c++

Christian Graus26-Dec-02 13:02

Christian Graus

26-Dec-02 13:02

managed c++ is a marketing con, C++ is the most widely used language on the planet for commercial applications.

Christian

No offense, but I don't really want to encourage the creation of another VB developer.
- Larry Antram 22 Oct 2002

C# will attract all comers, where VB is for IT Journalists and managers - Michael
P Butler 05-12-2002

Again, you can screw up a C/C++ program just as easily as a VB program. OK, maybe not
as easily, but it's certainly doable. - Jamie Nordmeyer - 15-Nov-2002

Re: c++ and managed c++

joshfl27-Dec-02 3:41

joshfl

27-Dec-02 3:41

thanks

Problems with drawing

S O S26-Dec-02 7:58

S O S

26-Dec-02 7:58

The CxImage *i is just an image that I want to get drawn onto this CDC.
It works fine if I Draw() straight to the window DC, but if i use this class and try to BitBlt() from this to the window DC, I get nothing.
What could be causing this?

class CSomeDC :<br />
	public CDC<br />
{<br />
	CBitmap bmp;<br />
	CBitmap *bmpOld;<br />
public:<br />
<br />
	Uint32 w, h;<br />
<br />
	void Init(CxImage *i)<br />
	{<br />
		w = i->GetWidth();<br />
		h = i->GetHeight();<br />
<br />
		VERIFY(CreateCompatibleDC(0));<br />
		VERIFY(bmp.CreateCompatibleBitmap(this, w, h));<br />
		bmpOld = (CBitmap*)SelectObject(bmp);<br />
		i->Draw(m_hDC);	// Works if I do this on the window DC straight away<br />
	}<br />
};

Re: Problems with drawing

Neville Franks26-Dec-02 10:02

Neville Franks

26-Dec-02 10:02

Locked Ghost wrote:
VERIFY(CreateCompatibleDC(0));

For a start why is 0 being passed here. It should be 'this' me thinks.

Neville Franks, Author of ED for Windows. www.getsoft.com
Make money with our new Affilate program

Re: Problems with drawing

S O S26-Dec-02 11:04

S O S

26-Dec-02 11:04

0 = Current display DC or something like that(Memory bad. From MSDN)

this? well, why would I want to create a DC compatible with itself, which has not been created yet? :p

For Mr.Locked Ghost

HellShrimp4free26-Dec-02 11:22

HellShrimp4free

26-Dec-02 11:22

hey Brian do u know Chris-de-Burgh ? Big Grin | :-D

-=Ehsan-de-Burgh=- Roll eyes | :rolleyes:

Re: For Mr.Locked Ghost

S O S26-Dec-02 21:47

S O S

26-Dec-02 21:47

Brian? Chris-de-Burgh? Never heard of either one

Re: Problems with drawing

Neville Franks26-Dec-02 13:00

Neville Franks

26-Dec-02 13:00

Locked Ghost wrote:
0 = Current display DC or something like that(Memory bad. From MSDN)

I think its for the Desktop. Is that what you want?

Locked Ghost wrote:
this? well, why would I want to create a DC compatible with itself, which has not been created yet? :p

Because that's what you do with memory dc's. Have a look around CP for CMemDC by Keith Rule.

Neville Franks, Author of ED for Windows. www.getsoft.com
Make money with our new Affilate program

Re: Problems with drawing

S O S26-Dec-02 21:49

S O S

26-Dec-02 21:49

Neville Franks wrote:
Because that's what you do with memory dc's. Have a look around CP for CMemDC by Keith Rule.

Tried, still doesn't work Frown | :(

And CMemDC does not do that actually.

Re: Problems with drawing

Iain Clarke, Warrior Programmer27-Dec-02 7:43

Iain Clarke, Warrior Programmer

27-Dec-02 7:43

I've run into this myself in the past. You are creating a DC which initially has a mono 1x1 bitmap
selected into it (look at ::CreateCompatible DC...) You need to create a HBITMAP compatible with the
end DC (e.g. Screen).

You need something like:

void Init (CxImage *i)
{
    CWindowDC dcScreen (CWnd::FromHandle (::GetDesktopWindow ()));

    w = i->GetWidth();
    h = i->GetHeight();

    VERIFY(CreateCompatibleDC(&dcScreen));    // <-- Changed to make it more obvious.
    ////////////////////////////
    VERIFY(bmp.CreateCompatibleBitmap(&dcScreen, w, h)); // <-- Changed
    ////////////////////////////
    bmpOld = (CBitmap*)SelectObject(bmp);
    i->Draw(m_hDC); // Works if I do this on the window DC straight away
}

I hope this helps,

Iain.

Re: Problems with drawing

S O S27-Dec-02 8:18

S O S

27-Dec-02 8:18

Yes!! It works Smile | :)

Huge thanks to you! Smile | :)

In related things, can you tellme why this destructor gives me an acccess violation?
I've seen the exact kind of thing(Selecting the old bitmap back) done in destructors before... hmm?

class CTilesetDC :<br />
	public CDC<br />
{<br />
	CBitmap bmp;<br />
	CBitmap *bmpOld;<br />
public:<br />
<br />
	Uint32 w, h;<br />
<br />
	CTilesetDC(CxImage *i, CDC *target)<br />
	{<br />
		w = i->GetWidth();<br />
		h = i->GetHeight();<br />
<br />
		VERIFY(CreateCompatibleDC(target));<br />
		VERIFY(bmp.CreateCompatibleBitmap(target, w, h));<br />
		bmpOld = (CBitmap*)SelectObject(bmp);<br />
		i->Draw(GetSafeHdc());<br />
	}<br />
<br />
	~CTilesetDC()<br />
	{<br />
		SelectObject(bmpOld);<br />
	}<br />
};

Re: Problems with drawing

Iain Clarke, Warrior Programmer28-Dec-02 13:11

Iain Clarke, Warrior Programmer

28-Dec-02 13:11

I should have spotted this in my first reply. CDC::SelectObject (CBitmap *) returns a pointer
to a temporary CBitmap. To quote:

This function may return a pointer to a temporary object. This temporary object is only valid
during the processing of one Windows message. For more information, see CGdiObject::FromHandle

After a while, the CBitmap pointed to by bmpOld is deleted by MFC; so when you try to delete it,
an exception is raised. This is one of the reasons I use HANDLES...

You could change your class to

<br />
class CTestDC : public CDC<br />
{<br />
    ....<br />
    CBitmap    bmpOld;<br />
    ....<br />
<br />
    CTestDC (....)<br />
    {<br />
        ....<br />
        bmpOld.Attach (SelectObject (&bmpNew)->Detach ());<br />
        ....<br />
    }<br />
<br />
    ~CTestDC ()<br />
    {<br />
        SelectObject (&bmpOld);<br />
        bmpOld.Detach (); // <-- If you don't do this, then ~CBitmap will call DeleteObject, which we don't to be purist...<br />
    }<br />
}<br />

I hope this helps.

Iain.

Metafile

Anthony988726-Dec-02 7:48

Anthony9887

26-Dec-02 7:48

I'm trying to resize of metafile. Is there a function I can use.

Thanks

SendMessage and BN_CLICKED doesn't work

User 665826-Dec-02 6:40

User 6658

26-Dec-02 6:40

Hi
I've got a real strange problem. I want to simulate a button-press in another app. I have a HWND wndButton, which is definately valid. Now I want to simulate the pressing of the button:
::SendMessage(::GetParent(wndButton),WM_COMMAND,MAKEWORD(::GetDlgCtrlID(wndButton),BN_CLICKED),(LPARAM)wndButton);
But this doesn't work. Does anybody know why? It works in other programs Confused | :confused:

Update: The window doesn't even react on ShowWindow(SW_HIDE), although my HWND to the window is valid. What the hell is going on here? Eek! | :eek:

regards
Greg

modified 12-Sep-18 21:01pm.

Re: SendMessage and BN_CLICKED doesn't work

AlexO26-Dec-02 6:51

AlexO

26-Dec-02 6:51

Are you sure about "(::GetParent(wndButton),"? Parent might not be what you expect. Could you check it with Spy?

Re: SendMessage and BN_CLICKED doesn't work

User 665826-Dec-02 7:17

User 6658

26-Dec-02 7:17

Oh, forget my question, thanks for your effords Wink | ;)

This code was inside a loop that never was reached Big Grin | :-D

regards

modified 12-Sep-18 21:01pm.

Re: SendMessage and BN_CLICKED doesn't work

Brian Delahunty26-Dec-02 8:07

Brian Delahunty

26-Dec-02 8:07

Gregor S. wrote:
This code was inside a loop that never was reached

I don't like having to debug code but situations like this proves it's a complete necessity. Big Grin | :-D

Regards,
Brian Dela Smile | :)

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