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Use DrawText with the DT_CALCRECT format flag to just obtain the rectangle dimensions (the [in,out] lpRect parameter) then use again the function to actually write the string in the properly sized rectangle.
If the Lord God Almighty had consulted me before embarking upon the Creation, I would have recommended something simpler.
-- Alfonso the Wise, 13th Century King of Castile.
This is going on my arrogant assumptions. You may have a superb reason why I'm completely wrong.
-- Iain Clarke
[My articles]
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Thanks you, but, when the rectangle increases toward right ，rect.left is Fixed ,rect.right is changed,it's good, but increases toward left time, the rect.left and rect.right has had the change,why???
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You could try to draw in a calculated (CDC::GeTextExtent(..)) rectangle with a some fixed font and...
...in an applied zooming transformation (CDC::SetWorldTransform(..)) to the context.
So you can stretch the rectangle (with its content) like a gummi bear...
They sought it with thimbles, they sought it with care;
They pursued it with forks and hope;
They threatened its life with a railway-share;
They charmed it with smiles and soap.
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Hi guys,
I wanted to find out whether one can set up a test fixture to apply all tests to the same instance of the fixture object ?
Let's us take for an example the following Testclass implemented.
class SampleTest:: public CppUnit::TestFixture
{
CPPUNIT_TEST_SUITE( SampleTest);
CPPUNIT_TEST( doTest1);
CPPUNIT_TEST( doTest2);
public:
void doTest1();
void doTest2();
}
For each test in a test fixture, CppUnit creates a new instance of SampleTest class.
Thus for fixture SampleTest containing tests doTest1() and doTest2(), CppUnit will
create 2 instances of SampleTest class and calls doTest1 on the first instance, doTest2 on the second instance.
I would like to know if it is possible to create only one instance of SampleTest class that can call both the test functions?
Thanks in advance.
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cydd wrote: For each test in a test fixture, CppUnit creates a new instance of SampleTest class.
Correct, but it is not just before the test case function is called. The cpp unit is designed to collect all the test cases initially (this happens with macro CPPUNIT_TEST - see its definition), and map them against the an instance created for them. This is to make each test case purely independent. You have to set all the possible preconditions in each test case method in such a way that the testing will be meaningful for the context.
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Thanks for your reply.
Is there any other way to create only one instance of SampleTest class that can call on both the test functions?
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Can't you simply write a test function that in turn calls the other two functions?
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That will work.
But, the error report generated will not be of much help.
Say,if I have a function called testCaller() which in turn calls the two functions, doTest1 and doTest2 respectively.
If there happens an assertion failure in doTest1,the control returns without executing assert statements written in doTest2.
Also the report will say the test name only as testCaller and not the relevant function (doTest1 in this case).
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I understand, but is that not an imaginary problem? The test should succeed. If you get an error, you would probably just go back and debug the test case anyway?
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Hi everyone,
I am trying to do simple line plotting, i have used a CStaticCtrl on which i am trying to plot a line on a button click event,this works fine for the first time,when the button is pressed for the second time,the value is not updated,i mean the previous line is not erased and the new line is drawn
My Code
void CMainWindow::OnPumpOffClicked()
{
CRect rect;
CDC *dc=m_pic1.GetDC();
CPen pen,*oldpen;
m_pic1.GetClientRect(&rect);// m_pic1 is variable for the static control
//dc->Rectangle(&rect);
pen.CreatePen(PS_SOLID,10,RGB(255,0,0));
oldpen=dc->SelectObject(&pen);
dc->SetMapMode(MM_ISOTROPIC);
dc->SetViewportOrg(0, 148);
dc->MoveTo(x1,y1);
dc->LineTo(x2,y2);
}
Any help is appreciated
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You really shouldn't put your drawing code in the mouse event. What you have to do instead is store the new lines coordinate when the button is clicked and refresh your control. This will call the OnPaint method in which you erase the background and draw all the lines that you stored.
If you want to use an existing charting control, you can also look at my sig: there's a link to such a control that I developed.
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Hey,
Thanks for the reply,sir i would be very kind of u if u please explain it more detail, i mean if u can just edit my code and show me in short,i know i am asking for too much from u,but the ctrls u have developed are like a bouncer for me,thanks again
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It's a bit too much code to write here but if you want an example, simply look at my chart control (the CChartCtrl class and more specifically the OnPaint method). What you are doing is drawing your stuff on your main window. You should in fact create a custom control and put the drawing code in your custom control (search for articles about custom controls, there are a couple for beginners on this website).
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Hi,
I have a dialog box application. It contains one list control (CListCtrl). It filled with some data. After double clicking on any row of it new modeless dialog gets opened.
My problem is after opening new modeless dialog box, the main dialog box's row on which i have double clicked should remain selected means display it partially that it is selected. So the user can see on which row he has double clicked previously though a modeless dialog box is opened.
If have any idea please reply.
Thanks in advance.
Regards
Rajendra
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Add the style LVS_SHOWSELALWAYS to the CListCtrl.
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Use List Control Properties Dialog.Select "Show Selection Always" so you can see your the item as selected item in List Control
I am a HUMAN. I have that keyword in my name........
 _AnsHUMAN_
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I want to fix the number of threads to spawn for a particular task and I do'nt know if that should depend on the number of logical processors or on the number of physical processors available to the system.
The number of physical processors can be read using the ::GetSystemInfo API while the ::GetLogicalProcessorInformation API returns the number of logical processors.
Any insight please ?
thx in advance.
Push Framework - now released !
http://www.pushframework.com
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[ADDED]
What follows is based on the assumption a lot of homogeneous work, mainly calculations, is to be performed and can be organized in a (small) number of threads without needing lots of synchronization. It would not apply to inhomogeneous operations, say some threads performing calculations, others disk I/O, others network I/O, etc.
[/ADDED]
In general I would base my considerations on the number of threads that can be active at the same time; this would ignore the physical aspects involved such as separate packaging, multi-core, hyper-threading... So the number of (logical) processors returned by GetSystemInfo() is what I would use.
The one exception would be applications where performance is dominated by cache efficiency; if so, what really matters is the number of separate level-2 caches available, which could be better approximated by the number of physical processors.
Hint: what would be keeping you from trying both? As your threading code would be dynamic anyway, why not perform an experiment? or even make it automatic: run with N threads for a while, then try 2*N and see if that is an improvement, then decide.
Luc Pattyn [Forum Guidelines] [My Articles] Nil Volentibus Arduum
Please use <PRE> tags for code snippets, they preserve indentation, improve readability, and make me actually look at the code. modified on Tuesday, February 8, 2011 5:10 PM
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Hi and thx for your reply.
The work is inhomegeneous, so the result of the experiment will surely show an increase of performance using 2*N threads.
That is the current number of threads I am using : #threads := c * #Physical Processors
where c is a constant that compensates for the non-zero probability that a thread could be in a blocking state within the task.
Exceeding this limit, will show a decrease of performance due to context switching.
My specific concern is with virtualized environment where most of our application execute nowadays.
The guest system is often allowed to "see" less processors than the host : I expect this to be true then :
#Physical Processors > #Logical Processors
Thus the c * #Physical Processors limit will exceed the actual number of threads that the system can actually execute in //.
Push Framework - now released !
http://www.pushframework.com
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here are some more thoughts:
- I'm not really familiar with virtual operations, however I expect the virtualisation widens the gap between your app's best performance and the number of physical processors even more, so I would not use the number of physical processors at all. I would rather use the number of logical processors, divided by some constant to compensate for how much of your system you want to dedicate to that app (maybe equal to the number of virtual systems).
- if your operations are not homogeneous and sometimes blocking (and assuming they have random blocking phases) but you can organize them in identical jobs, then you can add threads to execute said jobs until (a) performance no longer improves and/or (b) total CPU load reaches 100% or whatever number you want to allot to your virtual machine.
Luc Pattyn [Forum Guidelines] [My Articles] Nil Volentibus Arduum
Please use <PRE> tags for code snippets, they preserve indentation, improve readability, and make me actually look at the code.
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I see, the ideal is to use the logical processors then.
In your first reply I thought you meant the physical processors here, because you were talking about the ::GetSystemInfo API.
Luc Pattyn wrote: So the number of (logical) processors returned by GetSystemInfo() is what I would use.
Thanks !
Push Framework - now released !
http://www.pushframework.com
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Hi!
I need to make synchronization in my c++ function, and I don't know how to do that. Which library I can use?
( I heard about windows.h, but I don't see any methods for synchronization here... )
Thanks in advance!
Andry.
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create a critical section object CRITCAL_SECTION cs; initialize it then call ::EnterCriticalSection(&cs) and ::LeaveCriticalSection(&cs) to surround the code you want to protect.
Push Framework - now released !
http://www.pushframework.com
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Andry_st wrote: I need to make synchronization
Why ? is your application multithreaded ?
If no, don't bother.
If yes, have a look at mutex, semaphore, ...
read here : Thread Synchronization for Beginners[^]
Watched code never compiles.
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Yes, it is multithreaded.
Good link, thx.
Just one question: what I must to #include to enable this code?
How I can see, this is a windows.h functions, right?
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