Help with D3DXVECTOR2 pointers
Author
Looking for a little help with D3DXVECTOR2 pointers.
Say I write a simple function that takes a D3DXVECTOR2 structure and fills it out, obviously the D3DXVECTOR2 parameter has to be passed in as a reference. Something like this...
void ( D3DXVECTOR2 *position )
{
*position.x = 320;
*position.y = 240;
}
When I try and get this the compiler gives me an error.
: error C2228: left of ''.x'' must have class/struct/union type
: error C2228: left of ''.y'' must have class/struct/union type
So what is the proper way to do this?
Any help much appreciated, thanks.
The "proper" way to do that would be to use brackets:-
(*position).x = 320;
(*position).y = 240;
And an even properer way would be to use the arrow operator becuase position is s pointer, so to access the members of a pointer you should use the ''->'' operator like so:
position->x = 320;
position->y = 240;
or you could just make life easier and make the function like this
void something( D3DXVECTOR& position )
{
position.x = 320;
position.y = 240;
}
that way the original variable gets altered instead of a copy and it''s cleaner then using all that pointer and dereferencing stuffage.
:::: [ Triple Buffer V2.0 ] ::::
(*position).x = 320;
(*position).y = 240;
And an even properer way would be to use the arrow operator becuase position is s pointer, so to access the members of a pointer you should use the ''->'' operator like so:
position->x = 320;
position->y = 240;
or you could just make life easier and make the function like this
void something( D3DXVECTOR& position )
{
position.x = 320;
position.y = 240;
}
that way the original variable gets altered instead of a copy and it''s cleaner then using all that pointer and dereferencing stuffage.
:::: [ Triple Buffer V2.0 ] ::::
quote:
or you could just make life easier and make the function like this
void something( D3DXVECTOR& position )
{
position.x = 320;
position.y = 240;
}
I''ve always wondered this. What exactly is happening here? I know that the ''&'' symbol represents a reference, but then aren''t you passing in a reference, and therefore position is a pointer? How can you use the ''.'' operator then?
Because the C++ refrence operator operates at two levels. Under the hood it is only passing an address. However to the programmer it is treated as simply an "alias" for the original variable.
[edited by - Illumini on May 4, 2003 6:29:35 PM]
[edited by - Illumini on May 4, 2003 6:29:35 PM]
This topic is closed to new replies.
Advertisement
Popular Topics
Advertisement
