c++

Question on Virtual Methods

IF both methods are declared as virtual, shouldn't both instances of Method1() that are called be the derived class's Method1()? I am seeing BASE then DERIVED called each time. I am doing some review for an interview and I want to make sure I have this straight. xD class BaseClass { public: virtual void Method1() { cout << "Method...

QGLWidget + QGraphicsScene + QGraphicsView problem

Hi! I would like to create a simple thumbnail viewer using QGLWidget, QGraphicsScene and QGraphicsView. And I have a problem with placing QGLWidget on QGraphicsScene. The code is similar to this: QGraphicsScene *testScene = new QGraphicsScene (0, 0, 400, 400, 0); QGLWidget *testWidget1 = new QGLWidget(); testWidget1->renderText("Test ...

c++ problem, maybe with types...

Hi guys! I have a little problem in my code. The variables don't want to change their values. Can you say why? Here is my code: vector<coordinate> rocks(N); double angle; double x, y; // other code while (x > 1.0 || x < -1.0 || y > 1.0 || y < -1.0) { angle = rand() * 2.0 * M_PI; cout << angle << endl; cout << rocks[i - 1].x...

Compile C++ from VS08/10 without Run Time Library / MFC

Are there settings I can adjust in Visual Studio so that it does not compile with any run time library or MFC. I started learning C++ to get away from C#'s .Net, and this is just as bad. When I execute the program in a Windows XP virtual machine I get an error. I can compile without the dependencies in Code::Blocks, but I'm more familiar...

Can I use MFC objects in STL containers?

The following code doesn't compile for me in MSVC2005: std::vector<CMenu> vec(10); CMenu is an MFC menu object (such as a context menu). Through some testing I learned that CMenu does not have a public copy constructor. To do what I wanted to do, I needed to use a dynamic array. CMenu* menus = new CMenu[10]; // ... delete [] menus; ...

Function calculating the probability of a letter in an sentence

I have a function that is supposed to calculate the number of times a letter occurs in a sentence, and based on that, calculate the probability of it occurring in the sentence. To accomplish this, I have a sentence: The Washington Metropolitan Area is the most educated and affluent metropolitan area in the United States. An array o...

How does GetGlyphOutline function work? (WinAPI)

Basically I want to get bezier control points from a ttf font and then draw them. I was basically wondering 2 things. Does it return an array of points or is it more complex? How can you tell the points of 1 contour from another ex: the letter O which has 2 contours? Thanks ...

Only Integrating Box2D collision detection in my 2d engine?

I have integrated box2d in my engine, ( Debug Draw, etc. ) and with a world I can throw in some 2d squares/rectangles etc. I saw this post, where the user is basically not using a world for collision detection, however the user doesn't explain anything about how he's using the manifold (b2Manifold), etc. Another post, is in the cocos2d...

Constructors with inheritance in c++

If you have 3 classes, with arrows going from parent to child classes (i.e. "A -> B" means "B inherits from A": shape -> 2d shape -> circle +----> 3d shape -> sphere When you write your constructor for the circle class, would you ever just initialize the grandparent Shape object and then your current object, skipping the middle cla...

C++ increment operator

How to differentiate between overloading the 2 versions of operator ++ ? const T& operator ++(const T& rhs) which one? i++; ++i; ...

Stopping a runaway Lua subprocess

I have embedded Lua in an Objective-C application using LuaObjCBridge. I need to know how to stop the Lua process if it taking too much time (infinite loop?). Would running it in a separate thread help? ...

static const double in c++

Is this the proper way to use a static const variable? In my top level class (Shape) #ifndef SHAPE_H #define SHAPE_H class Shape { public: static const double pi; private: double originX; double originY; }; const double Shape::pi = 3.14159265; #endif And then later in a class that extends Shape, I use Shape::pi. I ge...

SIMPLE OpenSSL RSA Encryption in C/C++ is causing me headaches

SOLVED: I was dumb. First argument of encrypt should have been key.size() and first argument of decrypt should have been RSA_size(myKey). Hey guys, I'm having some trouble figuring out how to do this. Basically I just want a client and server to be able to send each other encrypted messages. This is going to be incredibly insecure bec...

Performance considerations when mixing C++ and Objective-C in same file

I have some high-performance C++ that I need to interface with Objective-C, is there any performance penalty to just dumping this code into a .mm file that contains my Objective-C code vs. leaving this code in a separate .cpp file and extern-ing all the functions I need to call from the .mm file? ...

Convert integer to formatted LPCWSTR. C++

I have a direct3d project that uses D3DXCreateTextureFromFile() to load some images. This function takes a LPCWSTR for the path to file. I want to load a series of textures that are numbered consecutively (ie. MyImage0001.jpg, MyImage0002.jpg, etc) But c++'s crazy strings confuse me. How do i: for(int i=0; i < 3;i++) { //How do I co...

./a.out termniated . Garbage output due to smashing of stack . How to remove this error ?

#include <iostream> #include <fstream> #include <cstring> using namespace std; typedef unsigned long int WORD; /* Should be 32-bit = 4 bytes */ #define w 32 /* word size in bits */ #define r 12 /* number of rounds */ #define b 16 /* num...

How to get my program to log the user into Windows?

i have been working on a program that will enter usernames and passwords if someone plugs in a Usb, but i don't know how to enter a windows log in password. So the idea is to have my program running so it can find if the usb is plugged in if so it will use keybd_event to enter the password and to hit enter. how would i get my program to ...

C++ multidimensional dynamic array

Let's say I have this to create a multidimensional array dynamically: int* *grid = new int*[gridSizeX]; for (int i=0; i<gridSizeX; i++) { grid[i] = new int[gridSizeY]; } Shouldn't be possible now to access elements like grid[x][y] = 20? ...

c++ exceptions and program execution logic

Hello everyone, I have been thru a few questions but did not find an answer. I wonder how should the exception handling be implemented in a C++ software so it is centralized and it is tracking the software progress? For example, I want to process exceptions at four stages of the program and know that exception happened at that specifi...

How to wrap two unmannaged C++ functions into two managed C# functions?

I've got two unmanaged C++ functions, Compress and Decompress. The arguments and returns go as followed: unsigned char* Compress (unsigned char*,int) unsigned char* Decompress (unsigned char*,int) Where all uchars are arrays of uchars. Could someone please help me lay out a way to convert these into managed C# code using the Byte[] a...