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I run the following code fragment to produce some graphics. The problem is it produces different results at different times.
Could this be a rounding error? And how can i fix ot
for (int col=0; col
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Code Fragement:
for (int col=0; col
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I presume you have a > as well as the <, which is causing your for loop to disappear. Use & and lt or gt to put a < or > if they are paired like an HTML tag.
What are you doing with iXVal ? You're using all whole numbers, so there's not going to be any rounding errors.
Christian
I have come to clean zee pooollll. - Michael Martin Dec 30, 2001
Sonork ID 100.10002:MeanManOzI live in Bob's HungOut now
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I'm not sure about evaluation order in C++, but probably, the expression:
x + (a * b / c)
will be evaluated as:
x + (a * (b / c))
if a, b and c are big enough, or multiple, or floating point, no problem, but in your case, if m_cols > 1, in the first loop pass, (col+1)/m_cols will evaluate as int(1/2). That's 0. So, iXVal == m_rectLocation.left, what's wrong.
If you do this:
int iXVal = m_rectLocation.left + (m_rectLocation.Width() * (col+1)) / m_cols;
That rewrite will force m_rectLocation.Width() * (col+1) to be evaluated before the division. There still will be rounding, but MUCH less problematic.
Crivo
Automated Credit Assessment
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Damn - I did not spot the divide. But I think divide and multiply have the same order of operation and evaluate left to right.
Christian
I have come to clean zee pooollll. - Michael Martin Dec 30, 2001
Sonork ID 100.10002:MeanManOzI live in Bob's HungOut now
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Yes, they do. Multiplication and divide evaluate left to right.
(a * (b / c)) != (a * b / c)
Tim Smith
Descartes Systems Sciences, Inc.
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How do i read and write to files in MFC?
thanks
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If your using MFC with the Doc\View architecture then check out the CArchive class used in the Serialize function in the CDocument derived class for which the wizard should generrate some code that looks like:
void CMyDoc::Serialize(CArchive& ar)
{
if (ar.IsStoring())
{
}
else
{
}
}
Hope this helps. Check out CArchive on MSDN here.
Giles
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Exist some message which is sent after a time when dialog and control are repainted ?? If I put the code in WM_PAINT and code draw where is the control i dont see anything.
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do you mean "what messages cause the repaint of the controls on a dialog" or do you mean "is there an automatic redraw message sent every xx seconds"
??
---
"every year we invent better idiot proof systems and every year they invent better idiots ... and the linux zealots still aren't being sterilized"
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I need draw resizeing box using CRectTracker and I dont know where i must put the code.
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If you draw in WM_PAINT and you don't see anything, it means your drawing code is broken. You can also draw in WM_ERASEBKGND if you're drawing the background of the dialog, to avoid flicker.
If you're doing something whereby you want the dialog repainted, you need to call Invalidate(), or Invalidate(FALSE) if you don't want to erase the dialog ( again to avoid flicker ).
Christian
I have come to clean zee pooollll. - Michael Martin Dec 30, 2001
Sonork ID 100.10002:MeanManOzI live in Bob's HungOut now
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I'm a little confused regarding InternetGetConnectedState().
If I run this function without a connection, dwFlags returns RAS, LAN and CONFIGURED
If I run this function with a connection, dwFlags returns RAS, MODEM and CONFIGURED
... so in truth, it doesn't appear that InternetGetConnectedState() is a very reliable test of whether or not you have an open connection. It seems to think that just because I have a LAN, that i must also be connected to the internet. Perhaps, it is merely testing for active ip traffic, sees the LAN, and hopes that it may be an internet source. I think this function simply returns true if it sees that you have a connectoid configured, regardless of whether you are connected
My only concern is that if it returns true, i assume a connection and then use other inernet sdk functions. If in fact there is not a connection, then a dialup is thrown. I don't want to throw up a dialup without first asking the user if they are ok for me to throw a dialup. Sure, i can inform them that running the functionality requires an internet connection and then they'll not be too surprised to see the dialup if i throw one. But as a developer, i'm obviously looking for the perfect solution.
I've also tried InternetAttemptConnect(0), and it always tell me that i am connected
I've also tried InternetCheckConnection(), and it always tells me that i am not connected
Whats a developer to do ? Is there any method that i can rely on ?
Jase
-------------------------------------------------------------------------------------------------------------------------------------------------------------------
View your digital photos and images with ease using the ultimate desktop image manager for Microsoft Windows
Download your free copy of SlideShow Desktop today from http://www.slideshowdesktop.com
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you don't want to try pinging a known ip address outside of your local network and seeing if you get a response?
---
"every year we invent better idiot proof systems and every year they invent better idiots ... and the linux zealots still aren't being sterilized"
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not really ... if your not connected it can take too long to timeout
Jase
-------------------------------------------------------------------------------------------------------------------------------------------------------------------
View your digital photos and images with ease using the ultimate desktop image manager for Microsoft Windows
Download your free copy of SlideShow Desktop today from http://www.slideshowdesktop.com
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Try using InetIsOffline
Nish
Sonork ID 100.9786 voidmain
www.busterboy.org
If you don't find me on CP, I'll be at Bob's HungOut
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But InetIsOffline() doesn't check for an internet connection. It merely checks to see if you have selected "Work Offline" in IE or Outlook.
<-- Snippet from MSDN -->
"Returns TRUE if the local system in not currently connected to the Internet. Returns FALSE if the local system is connected to the Internet or if no attempt has yet been made to connect to the Internet"
<-- Snippet End -->
By default, Windows assumes that you are connected to the internet as soon as you log on to Windows. The result of this is that InetIsOffline() will inform you that you are connected to the internet even if you are not, simply because you are not in 'Work Offline' mode ...
I'm beginning to doubt that the holy grail exists and am forming the opinion that there are no sdk or api functions that can reliably tell ou whether or not you are connected to the internet, and - this is the most important bit - not throw a dialup box if you are not connected.
?
Jase
-------------------------------------------------------------------------------------------------------------------------------------------------------------------
View your digital photos and images with ease using the ultimate desktop image manager for Microsoft Windows
Download your free copy of SlideShow Desktop today from http://www.slideshowdesktop.com
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oh, sorry!
Then your only option is to try and connect to some site.
Say try connecting to yahoo.com port 80 and if you can connect, you are online, else you are not.
Of course there is a danger that yahoo is down.
so try two other sites too just to be safe. Try say, microsoft.com and then try google.com
Nish
p.s. sorry if this is a really stupid idea, but I see no other way.
Sonork ID 100.9786 voidmain
www.busterboy.org
If you don't find me on CP, I'll be at Bob's HungOut
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Does anyone know of a free utility to make windows installer packages other than the one that you can download free at ms vc++ web page.
Microsoft only let you have it if you have the devstudio enterprise or advanced edition, and i only have the standard.
==================================================
When Your Mind Wonders...Where Does It Go???
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These are both very popular and free. The Nullsoft installer includes full source code.
/ravi
"There is always one more bug..."
http://www.ravib.com
ravib@ravib.com
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Hi. I have a class that is responsible for opening, closing, and doing everything for a wave device (wave in only). It is derived from CWinThread, and I have the callbacks for the wave device send thread messages to it. The messages are WM_WIM_CLOSE, WM_WIM_OPEN, and WM_WIM_DATA. In the WM_WIM_CLOSE message handler, I want the thread to quit, so I have a call to ::PostQuitMessage (0). This works the first few times I open and close a wave device, but then the debugger breaks and says in the output "HEAP[recorder.exe]: HEAP: Free Heap block 151338 modified at 151358 after it was freed". Why would it be doing this? Any ideas?
Another problem: Sometimes (not always), I get similar symptons when the device in opened, only it breaks when I call ::waveInOpen (). Same type of error in the output. I can continue the program and it doesn't seem to be huring anything, but it still concerns me and is anoying when I run the program in debug mode because it always stops. Has anyone ever experienced these problems? Thanks in advance.
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drummer wrote:
Free Heap block 151338 modified at 151358 after it was freed
The CRT is catching a bug in your code. That message means that you allocated some memory, then later freed it, then wrote to the memory again using an old pointer that was still pointing at that block.
--Mike--
My really out-of-date homepage
Buffy's on. Gotta go, bye!
Sonork - 100.10414 AcidHelm
Big fan of Alyson Hannigan.
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I figured it out. I wasn't doing any cross-thread syncronization, but I added it now using CMutex's and CSingleLock's. Now it works fine. Thanks though.
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In my Non-MFC application i need to use strtok, now i used it in another function and it works fine, but in one function it fails and I don't know why.
Here is the code from the function that works:
int fsConsole::ParseCommandLine(char* line)
{
char* funcname;
char* values;
funcname = strtok(line," ");
values = strtok(NULL, "\n");
return Execute(funcname, values);
}
Now here is the broken function:
int fsConfigManager::CreateSetting(char* settingName, void* value)
{
char* pComponent = strtok(settingName, ":");
if (pComponent == NULL)
return EFS_INVALID;
char* pSetting = strtok(NULL, "\n");
if (pSetting == NULL)
return EFS_INVALID;
ConfigList.insert(pair<char*, fsItem>(pComponent, fsItem(settingName, (char*)value)));
return EFS_OK;
}
When strtok is called in the second function i get an access violation.
Thanks in advance.
Stephen Caldwell
Blackfission, CEO
http://blackfission.myip.org:81
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