dynamic object growth

im making a class that will load and store all my textures. when the capacity is reached and you try to load/add a new texture, it should 'expand' the capacity

the code i've written works but when i quit the program i get a an error that pops up and says "Debug Error DAMAGE: after normal block ....." i know it is this function causing it but i dont know why, any ideas?

(MSVC++ 6)

Code:

void TexLoader::grow()
{
	int cap = capacity*1.8; // calculate new capacity
	Texture* temp;			// to hold temp data

	temp = textures;			 // make temp point to current textures
	textures = new Texture[cap]; // allocate new space for textures

	for(int j =0; j < index; j++) // copy textures to new array
	{
		textures[j].ID = temp[j].ID; 
		textures[j].tex = temp[j].tex;
	}

	capacity = cap;				// update capacity
	delete temp;				// delete old/temp objects
}

>>for(int j =0; j < index; j++)
Is index the correct value?

>>delete temp;
How many items is that deleting. Do you need to use []

Originally posted by Perspective
im making a class that will load and store all my textures. when the capacity is reached and you try to load/add a new texture, it should 'expand' the capacity

*cough*vector*cough*

>*cough*vector*cough*

lol, yeah, i know. but i like getting the experience of making my own things rather than always using STL items. if i were going to use one it would be more like...

*cough*map<string, texture>*cough*refernce them easily by name now*

>>for(int j =0; j < index; j++)
>Is index the correct value?

yes, index gets set to 0 in the constructor and is increased after each texture is added. once 'index >= capacity' i call the grow function.

>>delete temp;
>How many items is that deleting. Do you need to use []

doh! thats right. but it didnt fix the problem.
i can post the rest of the class if you want to see it but i know the problem is with this function ( when i allocate enough room to begin with, so the function doesnt get called, i dont get the error )


[edit] hmmmm..... weird. i only get the error when i start with space for 1 texture.

ex) i start with room for 1 texture, add 4 textures, get error... but
if i start with room for 2 textures, add 4 textures, everything works fine.
?

>>int cap = capacity*1.8;
Why *1.8, why not a whole number, like 2. Maybe the precision is causing a screw-up.

Originally posted by Hammer
>>int cap = capacity*1.8;
Why *1.8, why not a whole number, like 2. Maybe the precision is causing a screw-up.

2 just seemed a little big. not that 1.8 is much smaller. it was pretty much an arbitrary pick for testing.

...... omg ..... *reason hits me like a ton of bricks*

your right.
(as stated in my edit above ->) everything works fine as long as the initial capacity is > 1. duh, thats because 1*1.8 = 1 (integer mult.) and the capacity will never be able to expand if i start with 1. i cant believe i didnt pick up on that.
thanx for your help Hammer!!