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Thank you for answering, but no.
It was either MFC or WIN32 (before C#, .net etc)
What I do remember, the demo drew a polyline (orthogonal segments only) and allowed the user to move those points while keeping the orthogonality.
alex
'Architecture is music frozen in space.'
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Hi - I don't usually like to post questions which are "here's some code - why doesn't it work?" but I am well and truly stumped on this one...it's been more than a whole day's effort so far and it is 1025 on friday night and i'm still working on it....so i'd really appreciate some help...
I have two functions, one takes a buffer, turns it into PGM format (P6) and saves it to file....the other takes the buffer, turns it into PGM format in place and the calling function then returns the buffer and it is displayed
the saving to file one works a treat
<code>
/*
* writes a colour PGM file from a buffer
*/</code>
<code>
int write_P6(char *name, int W, int H, unsigned char *buf)
{
FILE *f;
int i, j;
if( (f = fopen(name, "w")) == NULL)
{
printf("Could not open >%s<\n", name);
return FALSE;
}
fprintf(f,"P6\n %d %d\n 255\n",W, H);
fflush(f);
for(i=0;i<H;i++)
{
for(j=0;j<W;j++)
{
fwrite(buf + (i * W + j)*3+2, 1, 1, f);
fwrite(buf + (i * W + j)*3+1, 1, 1, f);
fwrite(buf + (i * W + j)*3 , 1, 1, f);
}
}
fclose(f);
return TRUE;
}
</code>
and I am able to display the images just fine, but obviously this is sub-optimal and the disk accesses makes it real slow
so i want to use this function instead
<code>
/*********************************************************************/
/*
* changes a rgb buffer in place into PGM format without saving to disk
*/
int make_P6(int W, int H, unsigned char *buf)
{
int i, j;
unsigned char* temp;
temp = (unsigned char*)malloc(x * y *3+15);
sprintf(temp, "P6\n %d %d\n 255\n",W, H);
for(i=0;i<H;i++)
{
for(j=0;j<W;j++)
{
sprintf(temp, buf + (i * W + j)*3+2);
sprintf(temp, buf + (i * W + j)*3+1);
sprintf(temp, buf + (i * W + j)*3);
}
}
buf = (unsigned char*)realloc(buf, x * y *3+15);
buf = temp;
free(temp);
return TRUE;
}
</code>
the calling getframe function looks kinda like this:
<code>
unsigned char * getframe(int save_file)
{
int ret ;
ret = read(fd1, s, x * y);
if( ret != (x * y ) )
{
printf("We will have fragmented picture\n" );
}
nb_frame ++ ;
bayer2rgb24(d, s, x, y);
// at this point we should have a raw, RGB image
if( save_file )
{
write_P6("P6.pgm", x, y, d);
}
else
{
d = make_P6(x,y,d);
}
return d;
}
</code>
and the function which calls getframe knows whether to disregard the return value and open the file, or look at the return value for the pic....
now the problem comes in make_P6 --> the code just hangs at
<code> sprintf(temp, buf + (i * W + j)*3+2);
sprintf(temp, buf + (i * W + j)*3+1);
sprintf(temp, buf + (i * W + j)*3);</code>
- if i comment out these lines, there is no freeze (but clearly, nothing sensible happens to the image)....but if i leave them there, it just kinda waits....doing nothing....not crashing.....not taking up heaps of resources
it doesn't make any sense to me because the line
<code>sprintf(temp, "P6\n %d %d\n 255\n",W, H);</code>
works just fine....
i'll be eternally grateful if somebody can give me a hand
XX georgia 
-- modified at 8:40 Friday 7th April, 2006
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georgie.moss wrote: sprintf(temp, buf + (i * W + j)*3+2);
sprintf(temp, buf + (i * W + j)*3+1);
sprintf(temp, buf + (i * W + j)*3);
Of these three statements, only the last one is of any use since they are all writing to the same address. Is this your intent?
"Let us be thankful for the fools. But for them the rest of us could not succeed." - Mark Twain
"There is no death, only a change of worlds." - Native American Proverb
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sprintf expects to be working with NUL-terminated strings. If the buffer pointed to by buf + (i * W + j)*3+2 is garbage or does not have a NUL, it will keep looking for one. If that buffer contains a % it will try to format a value based on the contents of the stack, which would be bad considering to additional parameters are passed.
Are you sure you are not trying to do something like:
temp = (unsigned char*)malloc(x * y *3+15);
DWORD dwIndex = 0;
sprintf(temp, "P6\n %d %d\n 255\n",W, H);
for(i=0;i<H;i++)
{
for(j=0;j<W;j++)
{
DWORD dwBufIndex = ( i * W + j ) * 3 + 2;
temp[ dwIndex++ ] = buf[ dwBufIndex ]; <code>
temp[ dwIndex++ ] = buf[ --dwBufIndex ]; <code>
temp[ dwIndex++ ] = buf[ --dwBufIndex ]; <code>
}
} My math/indices may be off but I am sure you get what I am talking about...
Peace!
-=- James
If you think it costs a lot to do it right, just wait until you find out how much it costs to do it wrong!
Avoid driving a vehicle taller than you and remember that Professional Driver on Closed Course does not mean your Dumb Ass on a Public Road!
DeleteFXPFiles & CheckFavorites (Please rate this post!)
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thanks - changing from sprintf to direct buffer manipulation did the trick
really appreciate the help 
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Hi
I am trying to add a couple of items to the status bar in my SDI app, i can add one item on no problem, but when i add a second one on,
i get a message box appear saying "failed to create empty document"
in MainFrm i have
static UINT indicators[] =
{
ID_INDICATOR_CAPS,
ID_INDICATOR_NUM,
ID_INDICATOR_SCRL,
ID_INDICATOR_COUNT,
};
in the OnCreate
if (!m_wndStatusBar.Create(this) ||
!m_wndStatusBar.SetIndicators(indicators,
sizeof(indicators)/sizeof(UINT)))
{
TRACE0("Failed to create status bar\n");
return -1; // fail to create
}
m_wndStatusBar.SetPaneInfo(3,ID_INDICATOR_COUNT, SBPS_STRETCH, NULL );
in my resource.h
#define ID_INDICATOR_COUNT 59142
but if i try to add another option on i get the error
any ideas ??
Si
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IIRC, status bar indicators need to be string table entries, so try adding a string table entry for ID_INDICATOR_COUNT. Note that string table entries cannot be blank, and you will want to use enough characters for the width that the indicator will need.
For example, if you need to show a value range of 0-999999, I would create the string table entry with a string of "000000". You can set the value of the indicator using an ON_COMMAND_UPDATE_UI for the ID_INDICATOR_COUNT "control".
Peace!
-=- James
If you think it costs a lot to do it right, just wait until you find out how much it costs to do it wrong!
Avoid driving a vehicle taller than you and remember that Professional Driver on Closed Course does not mean your Dumb Ass on a Public Road!
DeleteFXPFiles & CheckFavorites (Please rate this post!)
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How much of characters could I store in a CString? I am having a function in which a CString has to be accepted. The input may be extremely large (Say about 700 pages, with 300 characters each page). Will CString be able to manage this? I know that I can chop the input to pieces and go ahead with the work. But I want to know how effective will be CString able to do this job. Thanks for your time..
Aljechin Alexander
![Rose | [Rose]](https://codeproject.global.ssl.fastly.net/script/Forums/Images/rose.gif)
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Aljechin How much of characters could I store in a CString? I
A CString can hold up to MAX_INT (2 billion) characters.
hope that helps
Si
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si_69 wrote: A CString can hold up to MAX_INT (2 billion) characters.
I think it's suports only 64KB, taking the amount of a new memory allocation. Am I wrong?
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Mihai Moga wrote: Am I wrong?
sure you are... it accepts up to 2 GB !!!
where di you get such an information ?
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v2.0 wrote: where di you get such an information
MSDN for Windows 3.1 
No offence meant, Mihai!
"We trained hard, but it seemed that every time we were beginning to form up into teams we would be reorganised. I was to learn later in life that we tend to meet any new situation by reorganising: and a wonderful method it can be for creating the illusion of progress, while producing confusion, inefficiency and demoralisation."
-- Caius Petronius, Roman Consul, 66 A.D.
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lol
ok, i understand better 
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Even if CString is able to store so much data, I don't think it is a good idea. Why do you want to store all this data in one CString ? What do you need to do with this data ? A better solution would probably to look at the data as smaller block and deal only with a single block at one time.
Just a suggestion.
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Yes yes. That is what I am exactly doing. But its crucial to complete the task soon as possible. The input comes from a microprocessor and the data is about the turbulence, velocity, temperature, etc of water flowing out of a dam. The input comes extremely fast. The faster we could complete the task and log it, the better it is. Thats why I asked this question. Thanks all.
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If you are already getting that data as a LPCTSTR (or const char *) stream, there is no reason to go through the overhead of putting that data into a dynamically-allocated buffer (the CString). If speed/performance is important, I would check to see if you can pass the data directly to the processing functions.
Peace!
-=- James
If you think it costs a lot to do it right, just wait until you find out how much it costs to do it wrong!
Avoid driving a vehicle taller than you and remember that Professional Driver on Closed Course does not mean your Dumb Ass on a Public Road!
DeleteFXPFiles & CheckFavorites (Please rate this post!)
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I did not put anything into a CString. Everything is unsigned char * here. That question just came into my mind.. So asked here. Thanks all.
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And how do you communicate with the microprocessor ? You receive data for example on the serial port ?
I don't think this is a great idea to store everything in a CString. They are used for string manipulatino and not as data buffer (I suppose that the data you are receiving is not only characters but also 'binary' data). And why not open a file at the begining of the communication and store everything there. Or even write your own data class that will take care of the format of the data. This could be quite fast if you design it well.
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Aljechin The input comes extremely fast
What does this mean? Compared to what? Using what medium (serial, ethernet, USB)?
When I face such a problem I tend to separate the data collection from the analysis.
I store the collected data in BLOBs, put them into a queue and analyze them in a separate thread.
Usually the analysis is non-critical regarding time compared to data collection.
Hope this helps
--
Roger
It's supposed to be hard, otherwise anybody could do it!
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Actually the program here is in Plain C with some asm stuff. But this question just came into my mind. I cannot use a CString even if I want it here. The data comes through a serial port. Actually there are two other layers after the microprocessor, from where the data comes to our program.
Thanks
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Aljechin The input comes from a microprocessor Aljechin The input comes extremely fast
If we are talking about currently commercially available PCs, "extremely fast" may be anything more than Gigabit-Ethernet.
In our company, we have a machine tha can generate data in a pace of about half of the capacity of a off-the-shelf IDE-Disk. (Not or long, though).
This is handeled in C++ on a standard PC.
"We trained hard, but it seemed that every time we were beginning to form up into teams we would be reorganised. I was to learn later in life that we tend to meet any new situation by reorganising: and a wonderful method it can be for creating the illusion of progress, while producing confusion, inefficiency and demoralisation."
-- Caius Petronius, Roman Consul, 66 A.D.
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InfiniBand - the only way to fly! 
Peace!
-=- James
If you think it costs a lot to do it right, just wait until you find out how much it costs to do it wrong!
Avoid driving a vehicle taller than you and remember that Professional Driver on Closed Course does not mean your Dumb Ass on a Public Road!
DeleteFXPFiles & CheckFavorites (Please rate this post!)
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That is ~205KB of data, which is a small amount of data in today's world.
Note that if you are copying the data directly into the CString in one shot, the performance will be MUCH better than if you keep appending into the CString.
If you need to be messing around with individual pages or lines a lot, you might want to use something else like an embedded editor (a hidden edit/richedit control, for example), or your own implementation of a text-row table (and array of pointers, one for each page/line) or something like that.
Lastly, it might be worth making sure that the function HAS to take a CString - there are lots of examples of poorly-designed code that take CString parameters unnecessarily, when a simple LPCTSTR would work fine.
Peace!
-=- James
If you think it costs a lot to do it right, just wait until you find out how much it costs to do it wrong!
Avoid driving a vehicle taller than you and remember that Professional Driver on Closed Course does not mean your Dumb Ass on a Public Road!
DeleteFXPFiles & CheckFavorites (Please rate this post!)
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Lastly, it might be worth making sure that the function HAS to take a CString - there are lots of examples of poorly-designed code that take CString parameters unnecessarily, when a simple LPCTSTR would work fine.
What really makes me twinge is when they specify a CString& - by reference! when an LPCTSTR would have been just fine 
People that start writing code immediately are programmers (or hackers), people that ask questions first are Software Engineers - Graham Shanks
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