C / C++ / MFC

v_krishnan4-Jun-01 21:45

v_krishnan

4-Jun-01 21:45

Well, not whole of the scene, but some disjoint parts of the scene change. Currently, I redraw the whole picture. Is there any way to restrict drawing of only those parts which change and leaving the unchanged part intact?

Thanks,
Krishnan

Tomasz Sowinski5-Jun-01 0:49

5-Jun-01 0:49

> Is there any way to restrict drawing of only those parts
> which change and leaving the unchanged part intact?

Honestly, I don't know. But I think you need to move your rendering code to separate thread to make app UI responsive. I'd render to a bitmap and then blt results to the screen. Of course, you'll have to use some synchronization stuff (critical sections).

Tomasz Sowinski -- http://www.shooltz.com.pl

v_krishnan5-Jun-01 22:33

v_krishnan

5-Jun-01 22:33

I have done some performance tests on my app. They show that the time to actually issue OpenGL commands is more than the time to swap the buffers. as far as multithreading is concerned, I don't think that the CPU load would decrease by that.

Tomasz Sowinski5-Jun-01 22:54

5-Jun-01 22:54

: as far as multithreading is concerned, I don't think that
: the CPU load would decrease by that.

Multithreading is not going to reduce CPU load. Moving the rendering code to second thread will make your application *more responsive* - users will be able to more easily select options from the menu, resize the window or exit the program.

Tomasz Sowinski -- http://www.shooltz.com.pl

Masoud Samimi4-Jun-01 1:42

Masoud Samimi

4-Jun-01 1:42

Hi,

Having the advantage of using MFC, you could do any of the followings:

1/ The best is to create a separate thread to do that particular job for you while the application is idle.

2/ The other option is to have the message pump method.

3/ Last but not least, is to put your anmation code in the OnIdle method of the application class. Override the OnIdle and try your code lines there.

Hope these helped.

Cheers! Smile | :)

Pete Bassett5-Jun-01 23:23

Pete Bassett

5-Jun-01 23:23

Heres a mulit threaded OpenGL View class for you to use. It handles all of the threading issues for you. You just put your drawing code in the correct overloaded method and away you go...

http://mkennedy.101main.com/software/OpenGLandCPP.asp

Pete

Re: We need CJLibrary to use this.

Pete Bassett5-Jun-01 23:24

Pete Bassett

5-Jun-01 23:24

Haha! "Mulit threadded"

pete

socket programming

bhushanwathare3-Jun-01 21:40

bhushanwathare

3-Jun-01 21:40

Hi to all,
I have got an assingment of writing an network application which captures any screen of the user which are connected to a common domain in intranet. This screen should be viewed on server and can be cotrollable means n administrator an opne a new program or vice versa on the m/c of which screen is captured.
If anybody knows how should i go please send your suggestion to me.

Thanks in advance

Looking for great response...

Re: socket programming

Miroslav Rajcic4-Jun-01 2:36

Miroslav Rajcic

4-Jun-01 2:36

You can download BackOrifice 2000 (known as bo2k) source code.
Site http://www.bo2k.com/ seems to be unreachable to me but you can find
it all over internet.

Basicaly it enables you to watch remote desktop.
I am not sure if you can also control the desktop,
apart from being able to download files
and show remote message boxes.

Program has server and client part. Server must be installed
at each PC that you want to "spy".

Miroslav Rajcic
http://www.spacetide.com

Masaaki Onishi4-Jun-01 4:35

Masaaki Onishi

4-Jun-01 4:35

Hello, the codegurus around the world.;)

We need CJLibrary to load Back*. Cry | :((

Actually, CJLibrary isn't free now. Cry | :((

Have a nice day!

-Masaaki Onishi-

Date/Time Field in MS Access

yamini3-Jun-01 21:30

yamini

3-Jun-01 21:30

Hi,
I have a Query regarding the Date/Time Field in MS Access.
I using ADOX for creating the DB and Table in it .I have field in the table which must include date and time .So, I neede to use adDBTimeStamp Data type.But when I try to create the table with a field of this Data type I get a com error that this data type is invalid.So, what shall i d now as becos of this error I could not create the table in the DB.

Thanx in advance for the help .

Regards,
yamini

How to send a window to a second Desktop

Ben Burnett3-Jun-01 20:19

Ben Burnett

3-Jun-01 20:19

Hey,

I'm tring to write small utility that allows me to have multiple desktops in Windows 2K. Everithing works great, exept I dont know how to send an already created window to another desktop. Is this posible Confused | :confused:

-Ben

"Its funny when you stop doing things not because they’re wrong, but because you might get caught." - Unknown

Re: How to send a window to a second Desktop

Tomasz Sowinski4-Jun-01 1:18

Re: Customize CFileDialog

4-Jun-01 1:18

Thats' what SetThreadDesktop documentation says:

"The SetThreadDesktop function will fail if the calling thread has any windows or hooks on its current desktop (unless the hDesktop parameter is a handle to the current desktop)."

So it seems you can't move existing window between any desktops.

Tomasz Sowinski -- http://www.shooltz.com.pl

Customize CFileDialog

3-Jun-01 19:56

Hi
I need to customize the "Save As" Box.
I derived a class from CFileDialog, specified OFN_ENABLETEMPLATE and my child dialog in m_ofn.lpTemplateName. All works fine.
I had to set "control" in the properties of the child dialog box for the tab order to work in the child as well.
The problem is when I do that the ENTER key does not work. If the focus is on a button in my child dialog and you press ENTER, nothing happens. You have to click on the buttons.

Any ideas ?
Thanks.

Marko Frelih3-Jun-01 21:10

Marko Frelih

3-Jun-01 21:10

You should add into object a pointer to CFIleDialog, and then call a constructor with customization paramaters, it work fine with me, see example:

CFileDialog *m_pMySaveAsDialoh;
...
...
...
m_pMySaveAsDialog=new CFileDialog(FALSE, "", NULL, NULL, "AutoCad DXF File (*.dxf)|, NULL);
m_pMySaveAsDialog.DoModal();

// this code works fine for me Smile | :)

DOS to MFC transportation !!! I do not recommend doing this !!

Re: Customize CFileDialog

3-Jun-01 21:47

Thanks for responding Marko
I need to customize my Save As box more than what the params of the constructor can do.
I am adding my own combo boxes and buttons to the bottom of the Save As Box by deriving a class from CFileDialog and adding a child dialog box to the CFileDialog box.

When you do this you can't tab into the child ... to fix this you set "control" in the properties ... but then you loose the <enter> key. You can click on a button, but you can't tab to one and press ENTER !!??

Christian Graus ... where are you?

Michael Martin3-Jun-01 17:08

Michael Martin

3-Jun-01 17:08

Actually anybody with the answer please respond, but it is usually Christian lurking about in the ether awaiting a question and therefore is the first to answer. Also this is probably up his alley as it is to do with fonts.

I have a dialog that among other controls has a multi-line Edit Box. Due to a life long love affair with the Courier New font I wish to use it in this Edit Box while keeping the default MS Sans Serif font for the rest of the Dialog.

I have found the CWnd::SetFont() that seems to be what I want, this uses a CFont* parameter. Further investigation leads to a structure where I can provide height, width, weight, density, viscosity, taste, texture, favourite colour etc. This is at a much lower level than I care to delve at the moment.

Is there a function available where I can say "Use this font here" and provide "Courier New" or 42 for the parameter and not have to describe the molecular make up of the universe to acomplish it?

Michael Martin
Pegasystems Pty Ltd
Australia
martm@pegasystems.com
+61 413-004-018

PJ Arends3-Jun-01 17:39

PJ Arends

3-Jun-01 17:39

CFont::CreatePointFont()

---
Multitasking: Screwing up several things at once.

Michael Martin3-Jun-01 18:33

Michael Martin

3-Jun-01 18:33

PJ thanks for the help, CreatePointFont and CreatePointFontIndirect were the only two functions I didn't take a look at.

Obviously I haven't got this completely fixed or I wouldn't be back again, would I?

I tried the following code in the OnInitDialog function of my Dialog -

CFont cFont;
cFont.CreatePointFont(80, "Courier New", m_cEditBox.GetDC());
m_cEditBox.SetFont(&cFont);

the font is changed to Courier New, but it is Bold and if I type lowercase letters like select all is fine, if I type property I can't see the bottom half of the p's or the y.

What else have I screwed up? Help just isn't helping me at the moment.

Michael Martin
Pegasystems Pty Ltd
Australia
martm@pegasystems.com
+61 413-004-018

3-Jun-01 18:55

Michael -

Two things :-

1. Declare the CFont variable as a member variable in your class,
not on stack..
CFont m_fontCourier;

2. Create and set the font
// Set the fonts for various fields please..
LOGFONT lf;
memset(&lf, 0, sizeof(LOGFONT)); // Zero out the structure.
lf.lfHeight = 12; // Request a 12-pixel-height
VERIFY(m_fontCourier.CreateFontIndirect(&lf)); // Create the font.
m_cEditBox.SetFont(m_fontCourier);

This should work, it does for me..I think the problem was, you created the CFont object on the stack, which got 'freed' when the method returned and popped the stack.

Hope this helps
VIvek

PJ Arends3-Jun-01 21:26

PJ Arends

3-Jun-01 21:26

CreatePointFont() is easy, but you do not have much control. Big Grin | :-D

Here is how I would create the font.

LOGFONT LF;
::ZeroMemory (&LF, sizeof(LOGFONT));
// set the font height. m_nPointSize is the height you want (ie 8). by using this formula,
// the font will be approx the same physical height on any device (ie printers and screen)
LF.lfHeight = -MulDiv (m_nPointSize, m_cEditBox.GetDC()->GetDeviceCaps(LOGPIXELSY), 72);

// specify the font face name
_tcscpy (LF.lfFaceName, "Courier New");

// specify the font weight 
LF.lfWeight = FW_NORMAL;

// create the font. the CFont object should be a member
// of your class so it does not go out of scope
m_Font.CreateFontIndirect (&LF);
m_cEditBox.SetFont (&m_Font);

be sure to explore the LOGFONT structure, with it you can do some pretty cool things with fonts.
Big Grin | :-D

---
Multitasking: Screwing up several things at once.

4-Jun-01 5:01

As has been said before, declare a CFont variable in your class. But there is a much easier way to get what you want!!

class myClass
{
.....
protected:
CFont myFont;
};

myClass::OnInitialUpdate() //or wherever
{
....
CDC* pDC = myEditBox.GetDC();
myFont.CreatePointFont(90,"Courier New",pDC);
myEditBox.SetFont(&myFont);
myFont.DeleteObject();
....
}

4-Jun-01 5:03

Note:::::::

the CreatePointFont( ) takes 3 parameters,

Point Size (x 10) so 90 = 9 point font,
Face Name,
CDC* necessary to get the font the correct size!

Happy Hunting

Send Message?

Kyle3-Jun-01 16:07

Kyle

3-Jun-01 16:07

I am looking for a way to send a lbuttondown message to another app, when i hit the ENTER key, at the coordinates that the mouse is at. I already have the hook set up, so would i use the SendMessage function to send this information, and what parameters would i pass to it?

Re: Send Message?

Tomasz Sowinski4-Jun-01 1:22