Is this 2D array initialization a bad idea?
- by Brendan Long
I have something I need a 2D array for, but for better cache performance, I'd rather have it actually be a normal array. Here's the idea I had but I don't know if it's a terrible idea:
const int XWIDTH = 10, YWIDTH = 10;
int main(){
int * tempInts = new int[XWIDTH * YWIDTH];
int ** ints = new int*[XWIDTH];
for(int i=0; i<XWIDTH; i++){
ints[i] = &tempInts[i*YWIDTH];
}
// do things with ints
delete[] ints[0];
delete[] ints;
return 0;
}
So the idea is that instead of newing a bunch of arrays (and having them placed in different places in memory), I just point to an array I made all at once.
The reason for the delete[] (int*) ints; is because I'm actually doing this in a class and it would save [trivial amounts of] memory to not save the original pointer.
Just wondering if there's any reasons this is a horrible idea. Or if there's an easier/better way. The goal is to be able to access the array as ints[x][y] rather than ints[x*YWIDTH+y].
