trying to make a simple grid-class, non-lvalue in assignment
- by Tyrfing
I'm implementing a simple C++ grid class. One Function it should support is accessed through round brackets, so that I can access the elements by writing mygrid(0,0). I overloaded the () operator and i am getting the error message: "non-lvalue in assignment".
what I want to be able to do:
//main
cGrid<cA*> grid(5, 5);
grid(0,0) = new cA();
excerpt of my implementation of the grid class:
template
class cGrid
{
private:
T* data;
int mWidth;
int mHeight;
public:
cGrid(int width, int height) : mWidth(width), mHeight(height) {
data = new T[width*height];
}
~cGrid() { delete data; }
T operator ()(int x, int y)
{
if (x >= 0 && x <= mWidth) {
if (y >= 0 && y <= mHeight) {
return data[x + y * mWidth];
}
}
}
const T &operator ()(int x, int y) const
{
if (x >= 0 && x <= mWidth) {
if (y >= 0 && y <= mHeight) {
return data[x + y * mWidth];
}
}
}
The rest of the code deals with the implementation of an iterator and should not be releveant.