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dynamic allocation of 2d array of pointers to a user defined type

 
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dynamic allocation of 2d array of pointers to a user defined type
Elkhirsawy
9 May, 2008 - 10:13 PM
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i am making a game and i have a general/base class called GameObject

i need to make dynamicly a 2-d array of pointers to GameObject and to intiallize it to null and i have done the following:

//in headerfile

GameObject ***h;

//in source file
//deaflt constructor defining unused values for x and y dimensions
MapMaker::MapMaker()
{
int x=5,y=5;
setfileName("Beginner.txt");

}

// function tht create the 2d array and intiallize it to null
void MapMaker::createMap(int xdimension, int ydimension)
{
h = new GameObject**[xdimension];
for (int i = 0; i<xdimension; i++)
h[i] = new GameObject*[ydimension];

for(int j=0;j<xdimension;j++)
{
for(int l=0;l<ydimension;l++)
{
h[j][l]=NULL;


}
}
cout<<"Map Created"<<endl;
}

it does not give a syntax error bt after the game was made objects move correctly on x dimension only.
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skaoth
RE: Dynamic Allocation Of 2d Array Of Pointers To A User Defined Type
10 May, 2008 - 01:40 PM
Post #2

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You need to modify your code to do this instead

CODE

GameObject **h = NULL;
....

h = new GameObject*[xdimension];
for (int i = 0; i<xdimension; i++)
{
    h[i] = new GameObject[ydimension];
}


Somehow you have an extra '*' in your deceleration. The for loop above
will create the objects not pointers. If you want pointers instead then simply change it. But remember if you want an array of pointers for the y dimension that you will have to new those objects as as well
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