I'm a newbie to C++ and I've been working on this Delaunay tree in C for some time. I'm ready to port it to C++ which does not mean that the code itself is completed or done.
But I was wondering, how could I design my code to fully utilize C++?
For one, I'm using C++'s built-in stack/queue/vector functions because it's a lot nicer than building my own stacks or queues lol.
So, here's an overview of the code.
The mesh is built of tetrahedrons so I have a "struct tetra" which stores pointers to vertices ("struct particle") and its 4 neighbours. Working in half-plane data, we have:
double a[4], b[4], c[4], d[4];//half-plane data
};
I'm fracturing these tetrahedrons by inserting vertices so I can get anywhere from 2 to 4 children per fracture per tetraheron. I'm mapping this history to a quadtree. This looks like :
Code:
struct tree {
int level;
struct tree *parent;
struct tree *children[4];
struct tetra *t;
};
What would be the best OO approach to this problem?
I thought about just using this object,
Code:
struct mesh {
struct tree *root; //pointer to root
/* insert all functions to be used by mesh here */
};
But I'm not sure how effectively this would be taking advantage of the OO paradigm.
Im having a problem with my sneaky hangman game I feel like im really close just getting an error I can't fix. When I run it, it says something like string subscript out of range when I goggled it. it says im searching past the bounds of what it should be or something.
Also a dictionary.txt file is needed to run the program
code: [URL]
#include <iostream> #include <string> #include <fstream> #include <vector> #include <algorithm> #include <map> using namespace std; int guessesUsed = 0; int wordlength;
I'm getting a bit lost in calling functions correctly. The assignment says to, reprogram this assignment using functions and include the additional features identified below -
Design your program so the main function invokes/calls functions to perform the following tasks:
4) sort the arrays in ascending order by student ID number
Here's what I've got thus far and I'm confused cuz I might be calling my function incorrectly.
Code: #include <stdio.h> #define MAX_ENTRIES 50 void s_ID (int student_ID[], int test_score[], char char_val[]); int main (void) {
I realize that implicit int rule was removed in C99 but gcc still takes this approach by default. I wonder why this happens:
bbb = 5; // legal int main(void) { aaa = 10; // illegal auto aaa = 10 // legal
Inside function a specifier is needed. Error message with no specifier used is:
error: ‘aaa’ undeclared (first use in this function)
Is this because of linkage - bbb variable has an external linkage so compiler knows that we are defining a variable here while inside mean() we need to show compiler that aaa is defined right here, it does not come from external functions?
will copy constructor does object initialization using another already created object? I understand that it can be applied for object initialization and not for assignment.Is it correct?
I have a method to take a Tile object and make an instances of it based on some data from the original object. Than it is suppose to manipulate the a specific instance and save the results. The first loop through it works but it changes all instance as well as the base.
public static int recurse(int count, Tile[,] b,Huristic h,int check) { if (check==1) { boardState.Add(B)/>; return check; } if (check == 0)
this function will return a temporary integer now void fun1(const int & num); this function can receive from myfun().BUT void fun2(int & num); this function cannot receive from myfun() Why is that, Moreover what is lifetime of a temporary object like one returned in myfun() ???
I am using the above code to retrive an item selected by user,But this line is giving an exception "Null Reference Exception, Object reference not set to an instance of an object"
In Visual Studio 2010 C++ I have a series of existing text objects The text properties names are item1_lbl, item2_lbl, item3_lbl, ….
Based on a selection I want to change an object. I generate the name of the object I want to change in a string so from this string is there a way to get a pointer to the correct text object that is same name?
I'm trying to figure out how I can create a vertex array object at offset of a vertex buffer object.I've created the buffer object. I'd like the "texs" idnex data to start at the texture coordinate content of the vertex_t structure.
Type definitions:
struct vertex_t { vector3d_t position; float s; // Texture coordinate s float t; // Texture coordinate t };
Code so far:
// How do I make this start at a certain spot of the VBO?! glVertexAttribPointer(texs, 2, GL_FLOAT, GL_FALSE, sizeof(vector3d_t), nullptr; //...
I have an assignment that asks me to implement a variant of the classic bouncing balls program.
'Each ball should start off at the top of the screen with a random speed in the x direction. Whenever a ball hits a screen boundary it should bounce off at an angle equal to the impact angle and lose some speed. Eventually each ball should come to a rest at the bottom of the screen. Five seconds after coming to a rest a ball should be removed from the screen.'
'Your code must keep track of objects (balls) by placing the object data structures in a linked list. You need to create your own linked list implementation. Below is a brief description of the object programming interface: CreateObject - Create a new object. The function accepts as input parameters a pointer to the SDL screen, a pointer to a model triangle array, and a variable telling the size of the model triangle array. The function returns a pointer to a new object data structure. The model triangle array specified as input parameter should not be shared across objects. (Not sharing the model triangle array allows e.g. objects to have different colors.)
Perform the necessary memory allocation and copying.DestroyObject - Free object. The function accepts as input parameters a pointer to an object data structure. The function should free all memory allocated to represent the object (memory allocated for the model triangle array and the object data structure itself).
Drawobject - Draw object on screen. The function accepts as input parameters a pointer to an object data structure. The function must draw the object on the screen by calling DrawTriangle on each of the model triangles. Remember to update scale, translation, etc., in each triangle data structure before invoking DrawTriangle.
Hint: Do not make the bouncing algorithm too complex. Bouncing a ball off a vertical or horizontal surface can be accomplished without resorting to calculating impact angles.'
The function I'm stuck at, is the first one - createobject.
I have two classes one called Date and the other is University , Date class has two overloaded operators , ostream and istream to take in the data and print them out :
The University class has an object of type Date called establishDate and I must use this to print out the date along with the University name and location, here's University class :
University.h
class University { public: University (); // constructor friend ostream & operator<<(ostream & out, University & x); // print the university data friend istream & operator>>(istream & in, University & x); // to read university data
it is not possible to get a type from an object, only from a type. Even with auto, you can only instantiate another type of the same type.I'd like to get a type from an object given another type, mainly because it is less typing and less error prone.
Some psudocode:
Type1 A<X, Y> a; int b; Type2 a.InnerType<b>::type c; // obviously won't work
A work around I thought of would be to use functions:
Type1 A<X, Y> a; int b; auto c = a.getInnerType(b);
Which is kinda interesting and looks like the way I'm going to go. However, I'm just wondering if there is any other ways of doing this as I don't really want to instantiate an object if I can avoid it (though the optimizer will probably just dump it anyway).
I have the following problem, I have an object of a class Subject, and I want that this object points to another object of class Classes, creating a kind of link. How can I do that?
So I am trying to develop a sort of 2d spacesim engine for creating games in C++. The project uses SFML for graphics, and I am currently trying to compile it on Linux using g++.
The main issue that I am wrestling with is that of simulation objects having their position, velocity, and rotation variables constantly getting set to NaN for reasons that are beyond me. The behaviour is not consistent, and occasionally will occur or not occur without any discernible pattern.
The github repo for the code is here: [URL] ....
I understand that NaN values can spread easily by operations on one another, but I cant seem to figure out where the initial issue is occurring here.
is it possible to get object name in the constructor? I would like to initialize an object of circle class without any arguments and put some pretty lines in constructor to get and save as table of chars the name of creating object. Is it possible? I work with MSVS2012.
int NextPixel(int antIndex, int currentPixel , Ant *ant , IplImage *edgeImg) { int left = currentPixel - 1 ; int right = currentPixel + 1 ; int up = currentPixel - edgeImg->widthStep ; int down = currentPixel + edgeImg->widthStep ;
[[Code] ....
if those lines are uncommented , program gives heap error.Why?