C / C++ / MFC

Re: load bitmap into memory

3-Dec-09 13:04

You can use the Image class to load a bitmap from a file.

«_Superman_»
I love work. It gives me something to do between weekends.

Microsoft MVP (Visual C++)

transoft4-Dec-09 2:18

transoft

4-Dec-09 2:18

I already load image from a file. But it displays very slow. I want to load data into memory.

Thanks

How to measure program speed?

Grimes3-Dec-09 6:31

3-Dec-09 6:31

Hi there

Can someone please help me. I am looking for a way to measure the speed of my program's execution. I am busy writing a simulation that needs to run as fast as possible and I want to make sure that the algorithms used are the fastest possible. Is there a way or a tool that can be used to measure the speed, like the amount of CPU clock cycles needed to complete an algorithm.

thank you in advance.

Riaan.

KOM UIT DAAAAA!!!

David Crow3-Dec-09 6:38

3-Dec-09 6:38

Have you tried the profiler that comes with Visual Studio?

"One man's wage rise is another man's price increase." - Harold Wilson

"Fireproof doesn't mean the fire will never come. It means when the fire comes that you will be able to withstand it." - Michael Simmons

Grimes3-Dec-09 6:45

3-Dec-09 6:45

I am not that familiar with visual studio, but I see there is a reference in the help to the profiler. It seems that it would be able to do what I want. I will look in to the profiler.

Thanks for pointing me in the right direction!

KOM UIT DAAAAA!!!

«_Superman_»3-Dec-09 8:19

3-Dec-09 8:19

Not sure if this is what you want but you could use high resolution timer functions like QueryPerformanceCounter/QueryPerformanceFrequency before and after a piece of executing code and compare their values.

«_Superman_»
I love work. It gives me something to do between weekends.

Microsoft MVP (Visual C++)

Grimes3-Dec-09 9:47

3-Dec-09 9:47

Hi
How would one use this?

QueryFrequencyCounter(Begin)
...CODE...
QueryFrequencyCounter(END)
TIME = END - BEGIN;

What is the unit of the counter? milliseconds or microseconds or clock cycles?

I will give it a try, thank you!

KOM UIT DAAAAA!!!

David Crow3-Dec-09 9:55

3-Dec-09 9:55

Grimes wrote:
What is the unit of the counter? milliseconds or microseconds or clock cycles?

See here and here.

«_Superman_»3-Dec-09 9:59

3-Dec-09 9:59

Here is an interesting blog - QueryPerformanceCounter counts elapsed time, not CPU cycles[^]

«_Superman_»
I love work. It gives me something to do between weekends.

Microsoft MVP (Visual C++)

Member 41945933-Dec-09 15:12

Member 4194593

3-Dec-09 15:12

Check the Masm32 forum. In the Laboratory there is a huge amount of information about timing, a Macro to set up the timing, and what it takes to get accurate results.

Grimes3-Dec-09 21:37

3-Dec-09 21:37

Thanks!!!

That counter macro seems to be counting the CPU cycles for a block of code. That does seem like the best way of determining the efficiency of a block of code, unlike time, that can vary greatly on different machines.

thanks for the help!

KOM UIT DAAAAA!!!

Using HDC thats NULL

dipuks3-Dec-09 6:06

dipuks

3-Dec-09 6:06

Hey

Can anyone tell what will happen if i use a HDC thats NULL?

For eg,

HDC hDc = {0};

DrawTextEx(hDc, ........);

I found that it will not throw an exception or something.

So is it OK to use like this?

Is there any MSDN documentation that talks about null HDC?

Thanks in advance

Re: Using HDC thats NULL

«_Superman_»3-Dec-09 6:15

3-Dec-09 6:15

That depends on the function you are using it in.
For example, the CreateCompatibleDC function says that if HDC is NULL it uses the current screen as the reference.

So if there is nothing mentioned about the behavior when HDC is NULL, if sure the behavior is undefined and you should not do that.

«_Superman_»
I love work. It gives me something to do between weekends.

Microsoft MVP (Visual C++)

Re: Using HDC thats NULL

dipuks3-Dec-09 7:17

dipuks

3-Dec-09 7:17

I am using HDC to write to a PDF printer. But the code is so entagled that, there's pieces of a text file writing code is also between that.

So when there's a case that only a text file need to be written and no PDF, then i pass the HDC for PDF as NULL.

So far in my testing i have seen that this works perfect.

Is there any other function that will return me a valid HDC, but will not mess up any text file writing?

Can i use CreateCompatibleDC to pass an HDC that will not mess up any other part of the application? But at the same time there will be a valid HDC rather than a NULL one.

Thanks

Re: Using HDC thats NULL

«_Superman_»3-Dec-09 7:55

Problem in running an application(developed in VC++ 2005) from windows service ..

3-Dec-09 7:55

I think I have too little understanding to give a reliable answer.
You will need to break up your question and isolate it from your domain if I need to understand.

«_Superman_»
I love work. It gives me something to do between weekends.

Microsoft MVP (Visual C++)

jain_MS3-Dec-09 5:27

jain_MS

3-Dec-09 5:27

Hi ,
While running an exe from service window , its throwing like

"The exception Unknown software exception (0x40000015) occurred in the application at location 0x781346b4."

Error 1067: the process terminated unexceptedly.

And in the Event viewer ...it is showing the message as ..

Faulting application mtserver.exe, version 6.2.86.0, faulting module msvcr80.dll, version 8.0.50727.4053, fault address 0x000046b4.

Note: its working fine in debug mode.

Please let me know ur valuable comments.

Ur help much appreciated

Regds
Jain

Re: Problem in running an application(developed in VC++ 2005) from windows service ..

«_Superman_»3-Dec-09 5:55

Memory allocation in multi-threaded application

3-Dec-09 5:55

Does it fail even if the EXE is executed by double clicking from user mode?
If so try attaching a debugger to the process.
You could try running the EXE in debug mode, but without attaching the debugger (Ctrl + F5).

«_Superman_»
I love work. It gives me something to do between weekends.

Microsoft MVP (Visual C++)

baerten3-Dec-09 5:08

baerten

3-Dec-09 5:08

Hi everybody,

I like to find out where a function or maybe an entire library allocates a huge amount of memory.
In the task-manager I see that the application really uses 25MB of the memory and allocates a total of 166MB.

I tested already GlowCode, but it displays only the memory which is really in use.
Is there another tool or programming technique to find the call of the function?

Big thanks for any help Smile | :)

Re: Memory allocation in multi-threaded application

David Crow3-Dec-09 5:42

Re: Memory allocation in multi-threaded application

3-Dec-09 5:42

baerten wrote:
Is there another tool or programming technique to find the call of the function?

crewchill3-Dec-09 12:18

crewchill

3-Dec-09 12:18

I think he meant which code calls the heap allocator?

Try IBM Rational Purify. They have 30-day license I believe. It should keep track of allocations and deallocations, leaks, etc, complete with the stack of the callers.

i'm foolish, so you can help me very easy

nenfa3-Dec-09 3:38

nenfa

3-Dec-09 3:38

i'm so foolish, who can help me?

i got one message identification, for example, it's 0x10b3, how can i get the described information about it?

as above is just one instance, if many message identification arise, i'll jump into whirlpool

Re: i'm foolish, so you can help me very easy

loyal ginger3-Dec-09 3:47

loyal ginger

3-Dec-09 3:47

Windows Message ID constants[^]

Re: i'm foolish, so you can help me very easy

David Crow3-Dec-09 3:48