C / C++ / MFC Discussion Boards

Rassul Yunussov26-Oct-04 13:10

26-Oct-04 13:10

i would like to write a letter in the center of the screen and rotate it, but when i rotate my later - it moves from the centre, who knows how to make it ?
I tried this:

CString str = "W";
	CFont Font;
	
	Font.CreateFont(96,                        // nHeight
					0,                         // nWidth
					angle*10,                         // nEscapement
					angle*10,                         // nOrientation
					FW_NORMAL,                 // nWeight
					FALSE,                     // bItalic
					FALSE,                     // bUnderline
					0,                         // cStrikeOut
					ANSI_CHARSET,              // nCharSet
					OUT_DEFAULT_PRECIS,        // nOutPrecision
					CLIP_DEFAULT_PRECIS,       // nClipPrecision
					ANTIALIASED_QUALITY,           // nQuality
					DEFAULT_PITCH | FF_SWISS,  // nPitchAndFamily
					"Arial");                 // lpszFacename
	dc.SelectObject(&Font);
	dc.Rectangle(0,0,100,100);
	CSize size = dc.GetTextExtent(str);
	int posx = 100-size.cx;
	int posy = 100-size.cy;
	dc.ExtTextOut(posx/2-sin(3.14*angle/180)*size.cx/2,posy/2+sin(3.14*angle/180)*size.cy/2,ETO_OPAQUE,NULL,str,NULL);

but it works properly only from 0 to 45...

Re: An algorithm question

Ryan Binns26-Oct-04 18:21

Ryan Binns

26-Oct-04 18:21

The problem is that the letter is rotating around its bottom-left corner. Use SetTextAlign() to centre the text so it will rotate around the centre of the letter.

Ryan

"Punctuality is only a virtue for those who aren't smart enough to think of good excuses for being late" John Nichol "Point Of Impact"

Re: An algorithm question

Rassul Yunussov1-Nov-04 18:28

Rassul Yunussov

1-Nov-04 18:28

I've tried SetTextAlign() method in many ways, but still without success - the maximum that i got is rotatig around it's bottom center, but i need the center of a letter... Please, help...

plotting library

Wonho Oh26-Oct-04 12:02

Wonho Oh

26-Oct-04 12:02

I am searching libaries for plotting 2d and 3d
which can be used with vc++.

Please recommend regardless of price.

I would appreciate when you email me at
woh@ams.sunysb.edu

Thank you all.

Re: plotting library

Arsalan Malik27-Oct-04 0:11

Arsalan Malik

27-Oct-04 0:11

OpenGL

ARSALAN MALIK

get Windows username

Anonymous26-Oct-04 11:44

Anonymous

26-Oct-04 11:44

Is there a quick and easy way to get the username of the current Windows user?

Re: get Windows username

Anonymous26-Oct-04 11:57

Anonymous

26-Oct-04 11:57

Figured it out myself:

GetEnvironmentVariable("USERNAME", username, username_size)

Re: get Windows username

Ryan Binns26-Oct-04 18:25

Ryan Binns

26-Oct-04 18:25

GetUserName() is the preferred solution, because in some security settings, applications may be prevented from reading environment variables.

Ryan

"Punctuality is only a virtue for those who aren't smart enough to think of good excuses for being late" John Nichol "Point Of Impact"

Re: get Windows username

ThatsAlok26-Oct-04 18:20

ThatsAlok

26-Oct-04 18:20

and here is second

[b]
GetUserName
The GetUserName function retrieves the user name of the current thread. This is the name of the user currently logged onto the system.

Windows 2000/XP: Use the GetUserNameEx function to retrieve the user name in a specified format. Additional information is provided by the IADsADSystemInfo interface.

BOOL GetUserName(
LPTSTR lpBuffer, // name buffer
LPDWORD nSize // size of name buffer
);
Parameters
lpBuffer
[out] Pointer to the buffer to receive the null-terminated string containing the user's logon name. If this buffer is not large enough to contain the entire user name, the function fails. A buffer size of (UNLEN + 1) characters will hold the maximum length user name including the terminating null character. UNLEN is defined in Lmcons.h.
nSize
[in/out] On input, specifies the maximum size, in TCHARs, of the buffer specified by the lpBuffer parameter. On output, receives the number of characters copied to the buffer, including the terminating null character.
If the buffer is too small, the function fails GetLastError returns ERROR_MORE_DATA. The nSize parameter receives the required buffer size.

[/b]

-----------------------------
"I Think It Will Help"
-----------------------------
Alok Gupta
visit me at http://www.thisisalok.tk

Interacting with a Digital Camera

Franz Klein26-Oct-04 11:22

Franz Klein

26-Oct-04 11:22

Does anybody know how to interact with a digital camera via an USB port in C++? I am using Windows XP and Visual Studio .NET 2003. I have looked for some source code examples but can't find any.

Cry | :((

I am the handsome one in the crowd.

Re: Interacting with a Digital Camera

Jörgen Sigvardsson26-Oct-04 11:38

Jörgen Sigvardsson

26-Oct-04 11:38

std::fstream is the answer Poke tongue | ;-P

Seriously though, most cameras shows up as removable media in Windows 2k/XP. So all you need to do is to read the images as files (JPG, GIF, whatever the camera uses). Any other communication over the USB connection is probably proprietary, and is probably not disclosed without an NDA.

--
Weiter, weiter, ins verderben.
Wir müssen leben bis wir sterben.

Re: Interacting with a Digital Camera

markkuk26-Oct-04 12:30

markkuk

26-Oct-04 12:30

There's a standard protocol for communicating with non-mass storage digital cameras: PIMA/ISO 15740 Picture Transfer Protocol (PTP). Many cameras can be switched between mass storage and PTP modes.
There's an Open Source (GPL) library for communicating with PTP cameras: libptp See also the USB Still Image Capture Device Definition

Cancel button in window not working

Xzyx987X26-Oct-04 9:55

Xzyx987X

26-Oct-04 9:55

I wrote a set of functions for displaying a progress window while CopyFileEx() runs. The only problem is that the cancel button on the window won't work. Well, actually it will work if I display a message box right before I create the window, which I haven't been able to explain yet... Anyway, here is the full code for it, less the headers:

//Include files////////////////////////////////////////////////////////////////////////////

#include "global_definitions.h"

#include <windows.h>
#include <commctrl.h>
#include "debug.h"
#include "memory.h"
#include "stringio.h"
#include "window_classes.h"

///////////////////////////////////////////////////////////////////////////////////////////



//Function prototypes//////////////////////////////////////////////////////////////////////

void InitProgressWindowClass(void);

int CopyFileProgressEx(LPCTSTR lpExistingFileName, LPCTSTR lpNewFileName, DWORD dwCopyFlags, HWND hWndParent, char * title, char * message, BOOL popup, DWORD parentUpdate);

DWORD WINAPI ProgressWindowThread(LPVOID lParam);

INT_PTR CALLBACK ProgressWindowProc(HWND hWnd, UINT uMsg, WPARAM wParam, LPARAM lParam);

LRESULT ProgressWindow_OnCreate(HWND hWnd, WPARAM wParam, LPARAM lParam);

DWORD CALLBACK CopyProgressRoutine(LARGE_INTEGER TotalFileSize, LARGE_INTEGER TotalBytesTransferred, LARGE_INTEGER StreamSize, LARGE_INTEGER StreamBytesTransferred, DWORD dwStreamNumber, DWORD dwCallbackReason, HANDLE hSourceFile, HANDLE hDestinationFile, LPVOID lpData);

///////////////////////////////////////////////////////////////////////////////////////////



//Function definitions/////////////////////////////////////////////////////////////////////

void InitProgressWindowClass(void)
{

    WNDCLASSEX wc = {0};

	//Register the progress window class
    wc.cbSize         = sizeof(wc);
    wc.lpszClassName  = "Progress Window";
    wc.hInstance      = GetModuleHandle(NULL);
    wc.lpfnWndProc    = ProgressWindowProc;
    wc.hCursor        = LoadCursor(NULL, IDC_ARROW);
    wc.hbrBackground  = (HBRUSH)GetSysColorBrush(COLOR_BTNFACE);
    wc.cbWndExtra     = sizeof(PROGRESSINFO *);

	RegisterClassEx(&wc);

}

int CopyFileProgressEx(LPCTSTR lpExistingFileName, LPCTSTR lpNewFileName, DWORD dwCopyFlags, HWND hWndParent, char * title, char * message, BOOL popup, DWORD parentUpdate)
{

	PROGRESSINFO * pip = ClearMemAlloc(sizeof(PROGRESSINFO));
	BOOL error;
	BOOL cancel = 0;
	DWORD threadId;

	if(!title)
		title = "";

	if(!message)
		message = "";

	pip->title = title;
	pip->message = message;

	pip->popup = popup;

	pip->cancel = &cancel;

	pip->hWndParent = hWndParent;

	pip->parentUpdate = parentUpdate;

	SetFocus(hWndParent);

	CreateThread(NULL, 0, ProgressWindowThread, pip, 0, &threadId);

	while(!pip->hWndProgress)
		Sleep(0);

	error = CopyFileEx(lpExistingFileName, lpNewFileName, CopyProgressRoutine, pip, NULL, dwCopyFlags);

	if(!error)
		return 1;
	else if(cancel)
		return 2;

	return 0;

}

DWORD WINAPI ProgressWindowThread(LPVOID lParam)
{

	MSG msg;
	DWORD exitCode = 0;
	PROGRESSINFO * pip = (PROGRESSINFO *) lParam;
	DWORD dwStyle = (pip->hWndParent != NULL ? WS_CHILD : 0) | WS_VISIBLE;
	RECT progressCords;

	if(pip->popup)
	{
		progressCords.left = GetSystemMetrics(SM_CXSCREEN) / 2 - PROGRESSWINDOW_WIDTH / 2;
		progressCords.top = GetSystemMetrics(SM_CYSCREEN) / 2 - PROGRESSWINDOW_HEIGHT / 2;

		dwStyle |= WS_POPUPWINDOW;
	}
	else
	{
		dwStyle |= WS_DLGFRAME;

		GetClientRect(pip->hWndParent, &progressCords);

		progressCords.left = (progressCords.right - progressCords.left) / 2 - PROGRESSWINDOW_WIDTH / 2;
		progressCords.top = (progressCords.bottom - progressCords.top) / 2 - PROGRESSWINDOW_HEIGHT / 2;
	}

	pip->hWndProgress = CreateWindowEx(
		0,
		"Progress Window",
		pip->title,
		dwStyle,
		progressCords.left,
		progressCords.top,
		PROGRESSWINDOW_WIDTH,
		PROGRESSWINDOW_HEIGHT,
		pip->hWndParent,
		NULL,
		GetModuleHandle(NULL),
		pip);

	while(GetMessage(&msg, NULL, 0, 0))
	{ 
		TranslateMessage(&msg); 
		DispatchMessage(&msg); 
	} 

	GetExitCodeThread(GetCurrentThread(), &exitCode);

	ExitThread(exitCode);

	ErrorMessage("Abnormal thread termination", NULL, NULL, MB_ICONEXCLAMATION, 1);

	return FALSE;

}

INT_PTR CALLBACK ProgressWindowProc(HWND hWnd, UINT uMsg, WPARAM wParam, LPARAM lParam)
{

	switch(uMsg)
	{

	case WM_CREATE:
		return ProgressWindow_OnCreate(hWnd, wParam, lParam);
		break;

	case WM_COMMAND:
		switch(LOWORD(wParam))
		{

		case BN_CLICKED:
			*(((PROGRESSINFO *)(GetWindowLongPtr(hWnd, GWL_USERDATA)))->cancel) = 1;
			break;

		}
		break;

	case WM_CLOSE:
		DestroyWindow(hWnd);
		break;

	case WM_DESTROY:
		free((void *) GetWindowLongPtr(hWnd, GWL_USERDATA));
		break;

	}

    return DefWindowProc(hWnd, uMsg, wParam, lParam);

}

LRESULT ProgressWindow_OnCreate(HWND hWnd, WPARAM wParam, LPARAM lParam)
{

	PROGRESSINFO * pip = *(PROGRESSINFO **) lParam;
	RECT rect;

	SetWindowLongPtr(hWnd, GWL_USERDATA, (LONG) pip);

	GetClientRect(hWnd, &rect);

	pip->progressBar = CreateWindowEx(
		WS_EX_CLIENTEDGE,
		PROGRESS_CLASS,
		NULL,
		WS_CHILD | WS_VISIBLE | PBS_SMOOTH,
		rect.left + 2,
		PROGRESSWINDOW_HEIGHT / 2 - GetSystemMetrics(SM_CYVSCROLL),
		rect.right - 5,
		GetSystemMetrics(SM_CYVSCROLL),
		hWnd,
		0,
		GetModuleHandle(NULL),
		NULL);

	pip->hWndStatic = CreateWindowEx(
		0,
		"Static",
		NULL,
		WS_CHILD | WS_VISIBLE | SS_CENTER,
		rect.left + 2,
		rect.top + 10,
		rect.right - 5,
		rect.top + 20,
		hWnd,
		0,
		GetModuleHandle(NULL),
		NULL);

	SetWindowText(pip->hWndStatic, pip->message);

	pip->hWndCancel = CreateWindowEx(
		0,
		"Button",
		NULL,
		WS_CHILD | WS_VISIBLE | BS_TEXT | BS_PUSHBUTTON,
		((rect.right - rect.left) / 2) + rect.left - 30,
		rect.bottom  - 30,
		60,
		24,
		hWnd,
		0,
		GetModuleHandle(NULL),
		NULL);

	SetWindowText(pip->hWndCancel, "Cancel");

	pip->hWndProgress = hWnd;

	SetFocus(pip->hWndCancel);

	return FALSE;

}

DWORD CALLBACK CopyProgressRoutine(LARGE_INTEGER TotalFileSize, LARGE_INTEGER TotalBytesTransferred, LARGE_INTEGER StreamSize, LARGE_INTEGER StreamBytesTransferred, DWORD dwStreamNumber, DWORD dwCallbackReason, HANDLE hSourceFile, HANDLE hDestinationFile, LPVOID lpData)
{

	int i;
	unsigned __int64 biasBit = 0x8000000000000000;
	int progressRange;
	int progressAchieved;
	PROGRESSINFO * pip = lpData;

	if(!pip->progressBias)
	{
		if(!(TotalFileSize.QuadPart & 0xFFFFFFFF80000000))
			pip->progressBias = 0;

		else  //Untested...
		{
			for(i = 33; i; i--)
			{
				if(biasBit & TotalFileSize.QuadPart)
					break;

				biasBit = biasBit>>1;
			}

			pip->progressBias = 32 - i;
		}
	}

	progressRange = (int) (TotalFileSize.QuadPart>>(pip->progressBias + 1));

	progressAchieved = (int) (TotalBytesTransferred.QuadPart>>(pip->progressBias + 1));

	SendMessage(pip->progressBar, (UINT) PBM_SETRANGE32, (WPARAM) 0, (LPARAM) progressRange);

	SendMessage(pip->progressBar, (UINT) PBM_SETPOS, (WPARAM) progressAchieved, (LPARAM) 0);

	if(pip->parentUpdate && pip->lastParentUpdate + pip->parentUpdate >= GetTickCount())
		UpdateWindow(pip->hWndParent);

	pip->lastParentUpdate = GetTickCount();

	if(TotalFileSize.QuadPart == TotalBytesTransferred.QuadPart)
	{
		PostMessage(pip->hWndProgress, WM_CLOSE, 0, 0);
		return PROGRESS_CONTINUE;
	}

	if(*pip->cancel)
	{
		PostMessage(pip->hWndProgress, WM_CLOSE, 0, 0);
		return PROGRESS_CANCEL;
	}
	else
		return PROGRESS_CONTINUE;

}

///////////////////////////////////////////////////////////////////////////////////////////

Streaming Audio

nlecren26-Oct-04 9:09

nlecren

26-Oct-04 9:09

Anyone know of any samples on how to write a streaming audio server??

Re: Streaming Audio

NietzscheDisciple26-Oct-04 9:45

NietzscheDisciple

26-Oct-04 9:45

Check out the DirectSound samples in the DirectX SDK.

The SDK does not provide an out-of-the-box streaming server solution. However the examples (in native C++ and in C#) give you a good introduction to the handling the audio data.

Can't comment about the network aspects.

Re: Streaming Audio

dharani26-Oct-04 21:14

dharani

26-Oct-04 21:14

Do u mean u want to stream uncompressed PCM format? if so u can refer Multimedia SDK .

Dharani babu S

redindian

sscanf question

act_x26-Oct-04 8:58

act_x

26-Oct-04 8:58

say i have
char strdata[100];
strcpy(strdata,"0.0000136");
float f;

the call
sscanf(strdata,"%f",&f) ; // works ok (ie f gets the correct value)
// but I cannot get

// need precision upto 6 places
sscanf(strdata,"%.6f",&f) ;

// I need formatted input
// to work
Please help .

scroll bar in vc++

Araj0126-Oct-04 8:50

Araj01

26-Oct-04 8:50

I have a graph which plots 14 million points. I want to include a scroll bar which would be sized based on the visible portion of the graph. initally all 14 million points are displayed. User can then use zoom function to zoom the graph where a max of 450 points can be seen. I am not able to include the scroll bar function. can anyone tell me what are the properties i need to set in the Scrollbar info structure?

thanks,

How to return string type in class

Cramp26-Oct-04 8:47

Cramp

26-Oct-04 8:47

First, I really appreciate that you spend your time to read my question.

Hi! I try to build a class that has several functions. Some of them will return string.
But my complier say I have something wrong.
The complier show the message that undefine error.
Please help me to figure out. Thank you.

I paste my complete code below

// filename:studentinfo.h
class studentinfo
{
public:
void set_lastname(string);
void set_firstname(string);
void set_ssn(string);
void set_age(int);
void set_phone(string);
string show_lastname();
string show_firstname();
string show_ssn();
int show_age();
string show_phone();
private:
string lastname;
string firstname;
string ssn;
int age;
string phone;
};
// filename:studentinfo.cpp
#include <iostream>
#include <string>
#include "studentinfo.h"
//--------------------------------------------------------------------------------
// The following functions declare for my class.
//--------------------------------------------------------------------------------
string studentinfo::show_lastname()
{
return lastname;
}
string studentinfo::show_firstname()
{
return firstname;
}
string studentinfo::show_ssn()
{
return ssn;
}
int studentinfo::show_age()
{
return age;
}
string studentinfo::show_phone()
{
return phone;
}
void studentinfo::set_lastname(string text)
{
lastname=text;
}
void studentinfo::set_firstname(string text)
{
firstname=text;
}
void studentinfo::set_ssn(string text)
{
ssn=text;
}
void studentinfo::set_age(int number)
{
age=number;
}
void studentinfo::set_phone(string text)
{
phone=text;
}

Re: How to return string type in class

LeeeNN26-Oct-04 8:57

LeeeNN

26-Oct-04 8:57

Are you sure it's string not CString? Laugh | :laugh:

Re: How to return string type in class

Nemanja Trifunovic26-Oct-04 8:59

Nemanja Trifunovic

26-Oct-04 8:59

Replace string with std::string

My programming blahblahblah blog. If you ever find anything useful here, please let me know to remove it.

Re: How to return string type in class

markkuk26-Oct-04 9:18

markkuk

26-Oct-04 9:18

The standard string type is std::string, you can add using namespace std; after the includes to avoid adding the std:: prefix everywhere.

time critical

LeeeNN26-Oct-04 8:19

LeeeNN

26-Oct-04 8:19

is there any way to guarantee a PC thread run at 200ms+_100ms period interval? Timer or multimedia timer seems don't fit.

Confused | :confused:

Re: time critical

Xzyx987X26-Oct-04 9:45

Xzyx987X

26-Oct-04 9:45

Well, there's always the Sleep() funtion. I'm not sure how gurenteed the amount of time it waits is though.

Edit: Just checked. It's not gurenteed to resume excecution after the given time period, but you could probobly fix that with a heavy priority boost or something.

Re: time critical

LeeeNN26-Oct-04 10:34

LeeeNN

26-Oct-04 10:34

Yes I set the thread to high priority, it still won't guarantee. by the way, what is heavy priority boost? Confused | :confused:

Use Ctrl+Left/Right to switch messages, Ctrl+Up/Down to switch threads, Ctrl+Shift+Left/Right to switch pages.