C / C++ / MFC

Christian Graus6-Aug-01 12:48

Christian Graus

6-Aug-01 12:48

I am just looking at our zooming code as it happens ;0)

The way I handle things in my paint program is that I do one thing before anything else every time the mouse moves: I call a function that takes into account the scroll position and zoom factor and stores the mouse position converted to bitmap co-ordinates. Then I always have a member variabl I can use to operate on the bitmap and I know exactly what part of the bitmap the mouse is pointing at. I'd suggest you do the same - if the user zooms, scrolls or moves the mouse, take these things into account and recalculate so that you know where on your 1:1 bitmap they are pointing.

Christian

Secrets of a happy marriage #27:

Never go to bed if you are mad at each other. It's more fun to stay up and fight.

Craig Miller6-Aug-01 12:57

Craig Miller

6-Aug-01 12:57

Christian,

Thanks so much for such information. I think the biggest problem I'm having is trying to figure out exactly where they are pointing. Is there some kind of formula that I can use to determine this information? I can get the zoom level from the Dundas COXSrollWnd class that I'm using. How is the conversion to bitmap coordinates done? Is there a CBitmap method that will do this for me?

Thanks again for all of your help, this has been an enlightening discussion for me to say the least,

Craig

Christian Graus6-Aug-01 13:23

Christian Graus

6-Aug-01 13:23

First of all you need to get the point that comes in, then you need to add the scroll positions. If it is zoomed you need to divide by the factor zoomed, in other words if you're zoomed in by a factor of 2, you need to divide by 2, because 10, 10 in mouse co-ords will point to 5,5 on the bitmap.

Here is my function:

	CPoint p = pt;

//	Figure out our mouse position, which is the cursor position, offset to allow for zooming and scrolling
	pt.x = pt.x + GetScrollPosition().x - m_XOffset;
	pt.y = pt.y + GetScrollPosition().y - m_YOffset;		

// Zoom > 0 means zoomed up, < 0 means zoomed down.  
        if (m_iZoom>0)
	{
		UINT divide = 1 << m_iZoom ;
		pt.x = (long)(((float) pt.x/(float) divide));
		pt.y = (long) (((float) pt.y/(float) divide));
	
	}
	else if (m_iZoom<0)
	{
		int multiply = 1 << (m_iZoom*-1);
		pt.x *= multiply;
		pt.y *= multiply;				
	}

In my case the zoom factor is not 1,2,3, but doubles every time in either direction, hence the shift operators. m_XOffset and m_YOffset are where the window is maximised and the bitmap is centered. There are lots of casts because I regard warnings as errors.

Christian

Secrets of a happy marriage #27:

Never go to bed if you are mad at each other. It's more fun to stay up and fight.

Craig Miller6-Aug-01 13:30

Craig Miller

6-Aug-01 13:30

That is excellent, thanks so much for your help in this matter, you make it seem so easy after I've been trying so hard for so long.

I will certainly give this a try, I'm sure it will work fine for me.

Thanks again,

Craig

Setting a value and reading values in registry

Christian Graus6-Aug-01 13:32

Christian Graus

6-Aug-01 13:32

No worries - always glad to help. Smile | :)

Christian

Secrets of a happy marriage #27:

Never go to bed if you are mad at each other. It's more fun to stay up and fight.

Iexplorer

calebcohoon6-Aug-01 10:34

calebcohoon

6-Aug-01 10:34

If I have a web page loaded inside of a mfc program, how can
i make one of the hyper links, in the page, run a dialog Smile | :)

Caleb

Re: Iexplorer

Not Active6-Aug-01 10:43

Not Active

6-Aug-01 10:43

One way would be to trick it. Set the hyperlink in question to some value that has meaning to you. THen override the OnBeforeNavigate method of the web browser control. Parse the URL and redirect it to open a dlg.

a href="opendlg" (would be nice to have

 tag support)

OnBeforeNavigate(LPCTSTR lpszURL, ...)
{
    if( !strcmp(lpszURL, "opendlg" )
        dgl.DoModal()
}

I've used this type of trick before. It might not be the best but it gets you there without having to implement IDocHostHandler and such. You could also do this with script on the page itself.

RobJones6-Aug-01 10:14

RobJones

6-Aug-01 10:14

Is there a "easy" or "best" way to insert a value into the registry using a MFC Dialog type application.. What I would like to do is..

Have a dialog type app, with a button that allows me to add a value\key to the registry this value would be pre-defined in the source code.. then whith a second button read\verify the registry key exists..

any ideas?

Rob Jones

Re: Setting a value and reading values in registry

Not Active6-Aug-01 10:36

Not Active

6-Aug-01 10:36

Look at RegCreateKey and the other related function.

Re: Setting a value and reading values in registry

RobJones6-Aug-01 11:56

RobJones

6-Aug-01 11:56

Thanks!!

Debug v. Release

flurinator6-Aug-01 9:51

flurinator

6-Aug-01 9:51

Hmm, I'm not sure if this is a common problem. I have a .dll that when compiled under Debug mode in VC++ 6.0, runs perfectly. But when I compile a Release version, the .dll can't correctly access the registry, redraw the window (I'm using InvalidateRect()), and will even throw an error when on exit.

So, I'm quite confused as to why this is happening. I don't really understand the difference between Debug and Release, I guess. Does anyone know what sort of compile options could be causing the problems I'm having?

thanks!

marc
m-flury@northwestern.edu

Baafie6-Aug-01 13:32

Baafie

6-Aug-01 13:32

I have the same problem, and I don't know what to do about it. Accessing the registry, that is. Are you using the OpenRegKeyEx or the function(I forgot its name)?

Baaf.

flurinator6-Aug-01 20:04

flurinator

6-Aug-01 20:04

I'm using CRegKey...

After reading the article recommended in the second reply, I'm betting my problems is my frequent use of the

assert(someFunction() == someVal);

programming no-no. Hope that helps!

flurinator6-Aug-01 20:04

flurinator

6-Aug-01 20:04

I'm using CRegKey...

After reading the article recommended in the second reply, I'm betting my problem is my frequent use of the

assert(someFunction() == someVal);

programming no-no. Hope that helps!

9-Sep-01 1:04

,
hai dear i am working e=with registry, my problem
1. i am able to registry key in debug mode where as in release mode it's not opening it's returning error code . if ur having suggestion kindly update me ASAP Rose | [Rose]

anshu

Bret Faller7-Aug-01 9:14

Bret Faller

7-Aug-01 9:14

ASSERT is ignored in Release versions so it doesn't matter if they're there or not.

Bret Faller
Odyssey Computing, Inc.

Michael Dunn6-Aug-01 14:05

Michael Dunn

6-Aug-01 14:05

Check out Surviving the Release Version

--Mike--
http://home.inreach.com/mdunn/
"Make sure that if you are using a blow torch that you don't set anything on fire."
-- Chris Maunder

CDynamicAccessor

Bret Faller6-Aug-01 9:30

Bret Faller

6-Aug-01 9:30

Good day,

Has anyone used CDynamicAccessor with OLEDB? If so, I need help inserting data into the recordset using SetData(...). I want to set the value for one column on the specific row. I am using CTable with CDynamicAccessor. I have all the properties needed (IRowsetUpdate/Change, etc.) but everytime I call SetData I get DB_E_ERRORSOCCURRED. Any examples, help is greatly appreciated. Thanks.

Bret Faller
Odyssey Computing, Inc.

Tomasz Sowinski6-Aug-01 10:25

Tomasz Sowinski

6-Aug-01 10:25

You may have been hit by issue described in KB article Q238539.

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

Bret Faller6-Aug-01 11:24

Bret Faller

6-Aug-01 11:24

I tried deriving a class and adding that support but still no go. I am using an ODBC driver because for some reason the Jet drivers don't support the options I need.

Bret Faller
Odyssey Computing, Inc.

Tomasz Sowinski6-Aug-01 11:37

Tomasz Sowinski

6-Aug-01 11:37

I am using an ODBC driver because for some reason the Jet drivers don't support the options I need.

Maybe ODBC over Jet doesn't support these options either. Anyway, you need to reduce your problem to some simple case: can you SetData on simple table with 1 integer column? Are you sure you're calling SetStatus for each field in accessor?

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